607 research outputs found
POS0758â DOES EXPERIENCE IN SYSTEMIC LUPUS ERYTHEMATOSUS INFLUENCE THE PHYSICIAN GLOBAL ASSESSMENT SCORING? A CROSS-SECTIONAL STUDY ON TWO EUROPEAN COHORTS
Background:The Physician Global Assessment (PGA) is an outcome instrument based on physician judgement of disease activity in patients with Systemic Lupus Erythematosus (SLE). Due to the subjectivity of the score and lack of standardization, the PGA could represent a source of heterogeneity, because the same manifestations could be rated differently by physicians with different backgrounds (1).Objectives:The purpose of this study was to evaluate the inter-rater reliability of PGA between a rheumatology trainee and rheumatologists expert in SLE from 2 european countries.Methods:SLE patients classified according to SLICC 2012 criteria were enrolled between May 2019 and December 2019 during a SLEuro traineeship program. Demographic, clinical (SLEDAI-2k, PGA), serological and ongoing medication data were collected. PGA was evaluated before (pre-lab) and after (post-lab) knowledge of laboratory exams, using a Visual Analogue Scale (VAS) ranging from 0 to 3, anchored at point 1 (mild), 2 (moderate) and 3 (severe activity). A trainee in Rheumatology (EC) and three rheumatologists experts in SLE (LA, MP, FS) independently scored the PGA for each patient.The trainee preliminarily received a standardization training with her tutor (MP), consisting of a shared discussion about 10 consecutive SLE outpatients to increase reliability in PGA scoring.Inter-rater reliability was analysed using the intraclass correlation coefficient (ICC) with a two-way single-rating model (2,1); 95% confidence interval (CI) was calculated.Results:Fifty-seven patients (86% female) affected from SLE (29 belonging to a French cohort and 28 to an Italian cohort) with a mean (SD) age 43.2 (15.9) years and a median [IQR] disease duration 6.4 [2.0-15.4] years were enrolled. Clinical features are presented in table 1. Pre-lab PGA scores were obtained from all patients and ranged from 0 to 2.3; post-lab PGA scores were obtained from 51 patients and ranged from 0 to 2.9. Inter-rater reliability of the PGA among the trainee was good to excellent for each lupus expert comparison: a) pre-lab PGA ICC 0.94, 95% CI 0.87-0.97; post-lab PGA ICC 0.94, 95% CI 0.87-0.97 (MP); b) pre-lab PGA ICC 0.84, 95% CI 0.63-0.93; post-lab PGA ICC 0.96 CI 0.88-0.99 (LA); c) pre-lab PGA ICC 0.91, 95% CI 0.65-0.98; post-lab PGA ICC 0.91, 95% CI 0.65-0.98 (FS).Conclusion:After an adequate standardization, PGA scoring reaches good to excellent reliability between trainee and experts.References:[1]Chessa E, Piga M, Floris A, Devilliers H, Cauli A, Arnaud L. Use of Physician Global Assessment in systemic lupus erythematosus: a systematic review of its psychometric properties. Rheumatology (Oxford). 2020 Dec 1;59(12):3622-3632.Clinical DataCaucasian44 (77.2%)anti-dsDNA titre (median,IQR)14 (0-75)Hypocomplementemia (n,%)30 (54%)SLEDAIâĽ6 (n,%)18 (31.6%)SLEDAI (median,IQR)4 (2-6)Flares (n,%)18 (31.6%)Ongoing prednisone treatment (n,%)41 (71.9%)Prednisone dose mg (meanÂąsd)5 (0 - 8.9)Hydroxychloroquine (n,%)44 (77.2%)Immunosuppressant (n,%)35 (61.4%)Acknowledgements:Elisabetta Chessa gratefully acknowledges the SLEuro European Lupus Society for its financial support in her traineeship in Strasbourg.Disclosure of Interests:None declare
Non-Fermi liquid normal state of the Heavy Fermion superconductor UBe13
Non-Fermi liquid (NFL) behavior in the normal state of the heavy-fermion
superconductor UBe13 is studied by means of low-temperature measurements of the
specific heat, C, and electrical resistivity, \rho, on a high-quality single
crystal in magnetic fields up to 15.5 T. At B=0, unconventional
superconductivity forms at Tc=0.9 K out of an incoherent state, characterized
by a large and strongly temperature dependent \rho(T). In the magnetic field
interval 4 T \leq B \leq 10 T, \rho(T) follows a T^3/2 behavior for Tc(B)\leq T
\leq 1 K, while \rho is proportional to T at higher temperatures. Corresponding
Non-Fermi liquid behavior is observed in C/T as well and hints at a nearby
antiferromagnetic (AF) quantum critical point (QCP) covered by the
superconducting state. We speculate that the suppression of short-range AF
correlations observed by thermal expansion and specific heat measurements below
T_L \simeq 0.7 K (B=0) yields a field-induced QCP, T_L \to 0, at B=4.5 T.Comment: Presented at the M2S-2003 conference in Rio / Brazi
Solution of the Two-Channel Anderson Impurity Model - Implications for the Heavy Fermion UBe -
We solve the two-channel Anderson impurity model using the Bethe-Ansatz. We
determine the ground state and derive the thermodynamics, obtaining the
impurity entropy and specific heat over the full range of temperature. We show
that the low temperature physics is given by a line of fixed points decribing a
two-channel non Fermi liquid behavior in the integral valence regime associated
with moment formation as well as in the mixed valence regime where no moment
forms. We discuss relevance for the theory of UBe.Comment: 4 pages, 2 figures, (to be published in PRL
Effect of four plant species on soil 15N-access and herbage yield in temporary agricultural grasslands
Positive plant diversity-productivity relationships have been reported for experimental semi-natural grasslands (Cardinale et al. 2006; Hector et al. 1999; Tilman et al. 1996) as well as temporary agricultural grasslands (Frankow-Lindberg et al. 2009; Kirwan et al. 2007; Nyfeler et al. 2009; Picasso et al. 2008). Generally, these relationships are explained, on the one hand, by niche differentiation and facilitation (Hector et al. 2002; Tilman et al. 2002) and, on the other hand, by greater probability of including a highly productive plant species in high diversity plots (Huston 1997). Both explanations accept that diversity is significant because species differ in characteristics, such as root architecture, nutrient acquisition and water use efficiency, to name a few, resulting in composition and diversity being important for improved productivity and resource use (Naeem et al. 1994; Tilman et al. 2002). Plant diversity is generally low in temporary agricultural grasslands grown for ruminant fodder production. Grass in pure stands is common, but requires high nitrogen (N) inputs. In terms of N input, two-species grass-legume mixtures are more sustainable than grass in pure stands and consequently dominate low N input grasslands (Crews and Peoples 2004; Nyfeler et al. 2009; Nyfeler et al. 2011).
In temperate grasslands, N is often the limiting factor for productivity (Whitehead 1995). Plant available soil N is generally concentrated in the upper soil layers, but may leach to deeper layers, especially in grasslands that include legumes (Scherer-Lorenzen et al. 2003) and under conditions with surplus precipitation (Thorup-Kristensen 2006). To improve soil N use efficiency in temporary grasslands, we propose the addition of deep-rooting plant species to a mixture of perennial ryegrass and white clover, which are the most widespread forage plant species in temporary grasslands in a temperate climate (Moore 2003). Perennial ryegrass and white clover possess relatively shallow root systems (Kutschera and Lichtenegger 1982; Kutschera and Lichtenegger 1992) with effective rooting depths of <0.7 m on a silt loamy site (Pollock and Mead 2008). Grassland species, such as lucerne and chicory, grow their tap-roots into deep soil layers and exploit soil nutrients and water in soil layers that the commonly grown shallow-rooting grassland species cannot reach (Braun et al. 2010; Skinner 2008). Chicory grown as a catch crop after barley reduced the inorganic soil N down to 2.5 m depth during the growing season, while perennial ryegrass affected the inorganic soil N only down to 1 m depth (Thorup-Kristensen 2006). Further, on a Wakanui silt loam in New Zealand chicory extracted water down to 1.9 m and lucerne down to 2.3 m soil depth, which resulted in greater herbage yields compared with a perennial ryegrass-white clover mixture, especially for dryland plots (Brown et al. 2005).
There is little information on both the ability of deep- and shallow-rooting grassland species to access soil N from different vertical soil layers and the relation of soil N-access and herbage yield in temporary agricultural grasslands. Therefore, the objective of the present work was to test the hypotheses 1) that a mixture comprising both shallow- and deep-rooting plant species has greater herbage yields than a shallow-rooting binary mixture and pure stands, 2) that deep-rooting plant species (chicory and lucerne) are superior in accessing soil N from 1.2 m soil depth compared with shallow-rooting plant species, 3) that shallow-rooting plant species (perennial ryegrass and white clover) are superior in accessing soil N from 0.4 m soil depth compared with deep-rooting plant species, 4) that a mixture of deep- and shallow-rooting plant species has greater access to soil N from three soil layers compared with a shallow-rooting two-species mixture and that 5) the leguminous grassland plants, lucerne and white clover, have a strong impact on grassland N acquisition, because of their ability to derive N from the soil and the atmosphere
Managing risks to drivers in road transport
This report presents a number of case studies in managing risks to road transport drivers. The cases feature a variety of initiatives and interventions to protect drivers.In the road transport sector, as with any other, it is important to pay attention to working conditions in order to ensure a skilled and motivated workforce. Certain characteristics of the sector make it more difficult to practice risk management than in other sectors. But by taking account of how the sector operates in practice, and the characteristics of drivers themselves and the way they work, risks can be successfully manage
Magnetic Fields in the 3C 129 Cluster
We present multi-frequency VLA observations of the two radio galaxies 3C 129
and 3C 129.1 embedded in a luminous X-ray cluster. These radio observations
reveal a substantial difference in the Faraday Rotation Measures (RMs) toward
3C 129.1 at the cluster center and 3C 129 at the cluster periphery. After
deriving the density profile from available X-ray data, we find that the RM
structure of both radio galaxies can be fit by a tangled cluster magnetic field
with strength 6 microGauss extending at least 3 core radii (450 kpc) from the
cluster center. The magnetic field makes up a small contribution to the total
pressure (5%) in the central regions of the cluster. The radio morphology of 3C
129.1 appears disturbed on the southern side, perhaps by the higher pressure
environment. In contrast with earlier claims for the presence of a moderately
strong cooling flow in the 3C 129 cluster, our analysis of the X-ray data
places a limit on the mass deposition rate from any such flow of <1.2 Msun/yr.Comment: in press at MNRA
Superconductivity and Antiferromagnetism: Hybridization Impurities in a Two-Band Spin-Gapped Electron System
We present the exact solution of a one-dimensional model of a spin-gapped
correlated electron system with hybridization impurities exhibiting both
magnetic and mixed-valence properties. The host supports superconducting
fluctuations, with a spin gap. The localized electrons create a band of
antiferromagnetic spin excitations inside the gap for concentrations x of the
impurities below some critical value x_c. When x = x_c the spin gap closes and
a ferrimagnetic phase appears. This is the first example of an exactly solvable
model with coexisting superconducting and antiferromagnetic fluctuations which
in addition supports a quantum phase transition to a (compensated)
ferrimagnetic phase. We discuss the possible relevance of our results for
experimental systems, in particular the U-based heavy-fermion materials.Comment: 4 page
Mixed-valent regime of the two-channel Anderson impurity as a model for UBe_13
We investigate the mixed-valent regime of a two-configuration Anderson
impurity model for uranium ions, with separate quadrupolar and magnetic
doublets. With a new Monte Carlo approach and the non-crossing approximation we
find: (i) A non-Fermi-liquid fixed point with two-channel Kondo model critical
behavior; (ii) Distinct energy scales for screening the low-lying and excited
doublets; (iii) A semi-quantitative explanation of magnetic-susceptibility data
for UThBe assuming 60-70% quadrupolar doublet ground-state
weight, supporting the quadrupolar-Kondo interpretation.Comment: 4 Pages, 3 eps figures; submitted to Phys. Rev. Let
Monitoring Response to Radiotherapy in Human Squamous Cell Cancer Bearing Nude Mice: Comparison of 2â˛-deoxy-2â˛-[18F]fluoro-d-glucose (FDG) and 3â˛-[18F]fluoro-3â˛-deoxythymidine (FLT)
Objective: The uptake of 3â˛-[18F]fluoro-3â˛- deoxythymidine (FLT), a proliferation marker, was measured before and during fractionated radiotherapy to evaluate the potential of FLT-positron emission tomography (PET) imaging as an indicator of tumor response compared to 2â˛-deoxy-2â˛-[18F]fluoro-d-glucose (FDG). Materials and Methods: Nude mice bearing established human head and neck xenografts (HNX-OE; nu/nu mice) were locally irradiated (three fractions/week; 22 Gy) using a 150-kVp unit. Multiple FDG- and FLT-PET scans were acquired during treatment. Tumor volume was determined regularly, and tissue was analyzed for biomarkers involved in tracer uptake. Results: Both groups revealed a significant decline in tumor volume (Pâ<â0.01) compared to untreated tumors. For FDG as well as for FLT, a significant decline in retention was observed at day 4. For FLT, most significant decline in retention was observed at day 12; whereas, for FDG, this was already noted at day 4. Maximum decline in tumor-to-nontumor ratios (T/NT) for FDG and FLT was 42âÂąâ18% and 49âÂąâ16% (meanâÂą âSD), respectively. FLT uptake was higher then that of FDG. For FLT, statistical significant correlations were found for both tumor volume at baseline and at day 29 with T/NT and ÎT/NT. All tumors demonstrated expression of glucose transporter-1, thymidine kinase-1, and hexokinase II. No differences were found for amount of tumor cells and necrosis at the end of treatment. Conclusion: This new experimental in vivo model supports the promise of using FLT-PET, as with FDG-PET, to monitor response to external radiotherapy. This warrants further clinical studies to compare these two tracers especially in cancers treated with radiotherapy
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