A Experiência Das Avós De Crianças Com Câncer

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Evidence Levels for Neuroradiology Articles: Low Agreement Among Raters

BACKGROUND AND PURPOSE: Because evidence-based articles are difficult to recognize among the large volume of publications available, some journals have adopted evidence-based medicine criteria to classify their articles. Our purpose was to determine whether an evidence-based medicine classification used by a subspecialty-imaging journal allowed consistent categorization of levels of evidence among different raters. MATERIALS AND METHODS: One hundred consecutive articles in the American Journal of Neuroradiology were classified as to their level of evidence by the 2 original manuscript reviewers, and their interobserver agreement was calculated. After publication, abstracts and titles were reprinted and independently ranked by 3 different radiologists at 2 different time points. Interobserver and intraobserver agreement was calculated for these radiologists. RESULTS: The interobserver agreement between the original manuscript reviewers was -0.2283 (standard error = 0.0000; 95% CI, -0.2283 to -0.2283); among the 3 postpublication reviewers for the first evaluation, it was 0.1899 (standard error = 0.0383; 95% CI, 0.1149-0.2649); and for the second evaluation, performed 3 months later, it was 0.1145 (standard error = 0.0350; 95% CI, 0.0460-0.1831). The intraobserver agreement was 0.2344 (standard error = 0.0660; 95% CI, 0.1050-0.3639), 0.3826 (standard error = 0.0738; 95% CI, 0.2379-0.5272), and 0.6611 (standard error = 0.0656; 95% CI, 0.5325-0.7898) for the 3 postpublication evaluators, respectively. These results show no-to-fair interreviewer agreement and a tendency to slight intrareviewer agreement. CONCLUSIONS: Inconsistent use of evidence-based criteria by different raters limits their utility when attempting to classify neuroradiology-related articles.info:eu-repo/semantics/publishedVersio

Backward bifurcation, equilibrium and stability phenomena in a three-stage extended BRSV epidemic model

In this paper we consider the phenomenon of backward bifurcation in epidemic modelling illustrated by an extended model for Bovine Respiratory Syncytial Virus (BRSV) amongst cattle. In its simplest form, backward bifurcation in epidemic models usually implies the existence of two subcritical endemic equilibria for R 0 < 1, where R 0 is the basic reproductive number, and a unique supercritical endemic equilibrium for R 0 > 1. In our three-stage extended model we find that more complex bifurcation diagrams are possible. The paper starts with a review of some of the previous work on backward bifurcation then describes our three-stage model. We give equilibrium and stability results, and also provide some biological motivation for the model being studied. It is shown that backward bifurcation can occur in the three-stage model for small b, where b is the common per capita birth and death rate. We are able to classify the possible bifurcation diagrams. Some realistic numerical examples are discussed at the end of the paper, both for b small and for larger values of b

Prion Protein Misfolding Affects Calcium Homeostasis and Sensitizes Cells to Endoplasmic Reticulum Stress

Prion-related disorders (PrDs) are fatal neurodegenerative disorders characterized by progressive neuronal impairment as well as the accumulation of an abnormally folded and protease resistant form of the cellular prion protein, termed PrPRES. Altered endoplasmic reticulum (ER) homeostasis is associated with the occurrence of neurodegeneration in sporadic, infectious and familial forms of PrDs. The ER operates as a major intracellular calcium store, playing a crucial role in pathological events related to neuronal dysfunction and death. Here we investigated the possible impact of PrP misfolding on ER calcium homeostasis in infectious and familial models of PrDs. Neuro2A cells chronically infected with scrapie prions showed decreased ER-calcium content that correlated with a stronger upregulation of UPR-inducible chaperones, and a higher sensitivity to ER stress-induced cell death. Overexpression of the calcium pump SERCA stimulated calcium release and increased the neurotoxicity observed after exposure of cells to brain-derived infectious PrPRES. Furthermore, expression of PrP mutants that cause hereditary Creutzfeldt-Jakob disease or fatal familial insomnia led to accumulation of PrPRES and their partial retention at the ER, associated with a drastic decrease of ER calcium content and higher susceptibility to ER stress. Finally, similar results were observed when a transmembrane form of PrP was expressed, which is proposed as a neurotoxic intermediate. Our results suggest that alterations in calcium homeostasis and increased susceptibility to ER stress are common pathological features of both infectious and familial PrD models

Azimuthal anisotropy and correlations at large transverse momenta in p+pp+p and Au+Au collisions at sNN\sqrt{s_{_{NN}}}= 200 GeV

Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au+Au collisions at $\sqrt{s_{_{NN}}}$= 200 GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au+Au collisions to those in $p+p$ at the same energy. Elliptic anisotropy, $v_2$, is found to reach its maximum at $p_t \sim 3$ GeV/c, then decrease slowly and remain significant up to $p_t\approx 7$ -- 10 GeV/c. Stronger suppression is found in the back-to-back high-$p_t$ particle correlations for particles emitted out-of-plane compared to those emitted in-plane. The centrality dependence of $v_2$ at intermediate $p_t$ is compared to simple models based on jet quenching.Comment: 4 figures. Published version as PRL 93, 252301 (2004

Azimuthal anisotropy in Au+Au collisions at sqrtsNN = 200 GeV

The results from the STAR Collaboration on directed flow (v_1), elliptic flow (v_2), and the fourth harmonic (v_4) in the anisotropic azimuthal distribution of particles from Au+Au collisions at sqrtsNN = 200 GeV are summarized and compared with results from other experiments and theoretical models. Results for identified particles are presented and fit with a Blast Wave model. Different anisotropic flow analysis methods are compared and nonflow effects are extracted from the data. For v_2, scaling with the number of constituent quarks and parton coalescence is discussed. For v_4, scaling with v_2^2 and quark coalescence is discussed.Comment: 26 pages. As accepted by Phys. Rev. C. Text rearranged, figures modified, but data the same. However, in Fig. 35 the hydro calculations are corrected in this version. The data tables are available at http://www.star.bnl.gov/central/publications/ by searching for "flow" and then this pape

Measurement of the Cross Section for Prompt Diphoton Production in p-pbar Collisions at sqrt(s) = 1.96 TeV

We report a measurement of the rate of prompt diphoton production in $p\bar{p}$ collisions at $\sqrt{s}=1.96 ~\hbox{TeV}$ using a data sample of 207 pb$^{-1}$ collected with the upgraded Collider Detector at Fermilab (CDF II). The background from non-prompt sources is determined using a statistical method based on differences in the electromagnetic showers. The cross section is measured as a function of the diphoton mass, the transverse momentum of the diphoton system, and the azimuthal angle between the two photons and is found to be consistent with perturbative QCD predictions.Comment: 7 pages, 3 figures,revtex4. Version accepted by PRL, but with cross section tables i

Measurement of the Ratios of Branching Fractions B(Bs->Ds- pi+)/B(B0->D-pi+) and B(B+->D0bar pi+)/B(B0->D-pi+)

We report an observation of the decay Bs -> Ds- pi+ in p pbar collisions at sqrt(s) = 1.96 TeV using 115 pb^(-1) of data collected by the CDF II detector at the Fermilab Tevatron. We observe 83 +/- 11 Bs -> Ds- pi+ candidates, representing a large increase in statistics over previous measurements and the first observation of this decay at a p pbar collider. We present the first measurement of the relative branching fraction B(Bs -> Ds- pi+) / B(B0 -> D- pi+) = 1.32 +/- 0.18 (stat.) +/- 0.38 (syst.). We also measure B(B+ -> D0bar pi+) / B(B0 -> D- pi+) = 1.97 +/- 0.10(stat.) +/- 0.21(syst.), which is consistent with previous measurements

Measurement of the Ratio of Branching Fractions B(D0 -> K+ pi-)/B(D0 -> K- pi+) using the CDF II Detector

We present a measurement of R_B, the ratio of the branching fraction for the rare decay D0 -> K+ pi- to that for the Cabibbo-favored decay D0 -> K- pi+. Charge conjugate decays are implicitly included. A signal of 2005 +/- 104 events for the decay D0 -> K+ pi- is obtained using the CDF II detector at the Fermilab Tevatron collider. The data set corresponds to an integrated luminosity of 0.35 1/fb produced in p-bar/p collisions at sqrt{s}=1.96 TeV. Assuming no mixing, we find R_B = [ 4.05 +/- 0.21 (stat) +/- 0.11 (syst) ] x 10(-3). This measurement is consistent with the world average, and comparable in accuracy with the best measurements from other experiments.Comment: 7 pages, 3 figure

Automating Genomic Data Mining via a Sequence-based Matrix Format and Associative Rule Set

There is an enormous amount of information encoded in each genome – enough to create living, responsive and adaptive organisms. Raw sequence data alone is not enough to understand function, mechanisms or interactions. Changes in a single base pair can lead to disease, such as sickle-cell anemia, while some large megabase deletions have no apparent phenotypic effect. Genomic features are varied in their data types and annotation of these features is spread across multiple databases. Herein, we develop a method to automate exploration of genomes by iteratively exploring sequence data for correlations and building upon them. First, to integrate and compare different annotation sources, a sequence matrix (SM) is developed to contain position-dependant information. Second, a classification tree is developed for matrix row types, specifying how each data type is to be treated with respect to other data types for analysis purposes. Third, correlative analyses are developed to analyze features of each matrix row in terms of the other rows, guided by the classification tree as to which analyses are appropriate. A prototype was developed and successful in detecting coinciding genomic features among genes, exons, repetitive elements and CpG islands