3,094 research outputs found

    Convex hull test of the linear separability hypothesis in visual search

    Get PDF
    AbstractVisual search for a colour target in distractors of two other colours is dramatically affected by the configuration of the colours in CIE (x, y) space. To a first approximation, search is difficult when a target’s chromaticity falls directly between (i.e. is not linearly separable from) two distractor chromaticities, otherwise search is easy (D’Zmura [1991, Vision Research, 31, 951–966]; Bauer, Jolicoeur, & Cowan [1996a, Vision Research, 36, 1439–1466]; Bauer, Jolicoeur, & Cowan [1996b, Perception, 25, 1282–1294]). In this paper, we demonstrate that the linear separability effect transcends the two distractor case. Placing a target colour inside the convex hull defined by a set of distractors hindered search performance compared with a target placed outside the convex hull. This is true whether the target was linearly separable in chromaticity only (Experiments 1 and 2), or in a combination of luminance and chromaticity (Experiments 3 and 4)

    Prevalence of and factors associated with human cysticercosis in 60 villages in three provinces of Burkina Faso

    Get PDF
    Background : Taenia solium, a zoonotic infection transmitted between humans and pigs, is considered an emerging infection in Sub-Saharan Africa, yet individual and community-level factors associated with the human infection with the larval stages (cysticercosis) are not well understood. This study aims to estimate the magnitude of association of individual-level and village-level factors with current human cysticercosis in 60 villages located in three Provinces of Burkina Faso. Methodology/Principal Findings : Baseline cross-sectional data collected between February 2011 and January 2012 from a large community randomized-control trial were used. A total of 3609 individuals provided serum samples to assess current infection with cysticercosis. The association between individual and village-level factors and the prevalence of current infection with cysticercosis was estimated using Bayesian hierarchical logistic models. Diffuse priors were used for all regression coefficients. The prevalence of current cysticercosis varied across provinces and villages ranging from 0% to 11.5%. The results obtained suggest that increased age, being male and consuming pork as well as a larger proportion of roaming pigs and percentage of sand in the soil measured at the village level were associated with higher prevalences of infection. Furthermore, consuming pork at another village market had the highest increased prevalence odds of current infection. Having access to a latrine, living in a household with higher wealth quintiles and a higher soil pH measured at the village level decreased the prevalence odds of cysticercosis. Conclusions/Significance : This is the first large-scale study to examine the association between variables measured at the individual-, household-, and village-level and the prevalence odds of cysticercosis in humans. Factors linked to people, pigs, and the environment were of importance, which further supports the need for a One Health approach to control cysticercosis infection

    Essential Role of the G-Domain in Targeting of the Protein Import Receptor atToc159 to the Chloroplast Outer Membrane

    Get PDF
    Two homologous GTP-bindin proteins, atToc33 and atToc159, control access of cytosolic precursor proteins to the chloroplast, at Toc33 is a constitutive outer chloroplast membrane protein, whereas the precusor receptor atToc159 may be able to switch between a soluble and an integral membrane form. By transient expression of GFP fusion proteins, mutant analysis, and biochemical experimentation, we demonstrate that the GTP-binding domain regulates the targeting of cytosolic atToc159 to the chloroplast and mediates the switch between cytosolic and integral membrane forms. Mutant atToc159, unable to bind GTP, does not reinstate a green phenotype in an albino mutant (ppi2) lacking endogenous atToc159, remaining trapped in the cytosol. Thus, the function of atToc159 in chloroplast biogenesis is dependent on an intrinsic GTP-regulated swtich that controls localization of the receptor to the chloroplast envelope

    Consistent anomalies of the induced W gravities

    Get PDF
    The BRST anomaly which may be present in the induced WnW_n gravity quantized on the light-cone is evaluated in the geometrical framework of Zucchini. The cocycles linked by the cohomology of the BRST operator to the anomaly are straightforwardly calculated thanks to the analogy between this formulation and the Yang-Mills theory. We give also a conformally covariant formulation of these quantities including the anomaly, which is valid on arbitrary Riemann surfaces. The example of the W3W_3 theory is discussed and a comparison with other candidates for the anomaly available in the literature is presented.Comment: Latex, no figures, 12 pages (To appear on Physics Letters B.

    Mathematical formulation to predict the harmonics of the superconducting Large Hadron Collider magnets. II. Dynamic field changes and scaling laws

    Get PDF
    A superconducting particle accelerator like the LHC (Large Hadron Collider) at CERN, can only be controlled well if the effects of the magnetic field multipoles on the beam are compensated. The demands on a control system solely based on beam feedback may be too high for the requirements to be reached at the specified bandwidth and accuracy. Therefore, we designed a suitable field description for the LHC (FIDEL) as part of the machine control baseline to act as a feed-forward magnetic field prediction system. FIDEL consists of a physical and empirical parametric field model based on magnetic measurements at warm and in cryogenic conditions. The performance of FIDEL is particularly critical at injection when the field decays, and in the initial part of the acceleration when the field snaps back. These dynamic components are both current and time dependent and are not reproducible from cycle to cycle since they also depend on the magnet powering history. In this paper a qualitative and quantitative description of the dynamic field behavior substantiated by a set of scaling laws is presented.peer-reviewe

    Integrators of the Cytoskeleton that Stabilize Microtubules

    Get PDF
    AbstractSensory neurodegeneration occurs in mice defective in BPAG1, a gene encoding cytoskeletal linker proteins capable of anchoring neuronal intermediate filaments to actin cytoskeleton. While BPAG1 null mice fail to anchor neurofilaments (NFs), BPAG1/NF null mice still degenerate in the absence of NFs. We report a novel neural splice form that lacks the actin-binding domain and instead binds and stabilizes microtubules. This interaction is functionally important; in mice and in vitro, neurons lacking BPAG1 display short, disorganized, and unstable microtubules defective in axonal transport. Ironically, BPAG1 neural isoforms represent microtubule-associated proteins that when absent lead to devastating consequences. Moreover, BPAG1 can functionally account for the extraordinary stability of axonal microtubules necessary for transport over long distances. Its isoforms interconnect all three cytoskeletal networks, a feature apparently central to neuronal survival

    To eat or not to eat? Indicators for reduced food intake in 91,245 patients hospitalized on nutritionDays 2006-2014 in 56 countries worldwide: A descriptive analysis

    Get PDF
    Background: Inadequate nutrition during hospitalization is strongly associated with poor patient outcome, but ensuring adequate food intake is not a priority in clinical routine worldwide. This lack of priority results in inadequate and unbalanced food intake in patients and huge amounts of wasted food. Objectives: We evaluate the main factors that are associated with reduced meal intake in hospitalized patients and the differences between geographical regions. Design: We conducted a descriptive analysis of data from 9 consecutive, annual, and cross-sectional nutritionDay samples (2006-2014) in a total of 91,245 adult patients in 6668 wards in 2584 hospitals in 56 countries. A general estimation equation methodology was used to develop a model for meal intake, and P-value thresholding was used for model selection. Results: The proportion of patients who ate a full meal varied widely (24.7-61.5%) across world regions. The factors that were most strongly associated with reduced food intake on nutritionDay were reduced intake during the previous week (OR: 0.20; 95% CI: 0.17, 0.22), confinement to bed (OR: 0.49; 95% CI: 0.44, 0.55), female sex (OR: 0.53; 95% CI: 0.5, 0.56), younger age (OR: 0.74; 95% CI: 0.64, 0.85) and older age (OR: 0.80; 95% CI: 0.74; 0.88), and low body mass index (OR: 0.84; 95% CI: 0.79, 0.90). The pattern of associated factors was homogenous across world regions. Conclusions: A set of factors that are associated with full meal intake was identified and is applicable to patients hospitalized in any region of the world. Thus, the likelihood for reduced food intake is easily estimated through access to patient characteristics, independent of world regions, and enables the easy personalization of food provision

    Sainte-Marie-aux-Mines – Fouchelle

    Get PDF
    Fouillée depuis 2013, la cité ouvrière de la Fouchelle hébergeait des mineurs, des fondeurs et leurs familles. Elle s’étire le long d’un chemin horizontal, et d’un sentier en légère pente descendante qui s’en détache. On estime à une cinquantaine le nombre de maisons qui la composent, organisées en groupes de deux à cinq unités. Le groupe F2, proche du début de ce village du côté du vallon de Saint-Philippe, se compose d’un sous-groupe A, fouillé en 2017, et d’un sous-groupe B, fouillé en 201..

    The folding of 5′-UTR human G-quadruplexes possessing a long central loop

    Get PDF
    Abstract: G-quadruplexes are widespread four-stranded structures that are adopted by G-rich regions of both DNA and RNA and are involved in essential biological processes such as mRNA translation. They are formed by the stacking of two or more G-quartets that are linked together by three loops. Although the maximal loop length is usually fixed to 7 nt in most G-quadruplexpredicting software, it has already been demonstrated that artificial DNA G-quadruplexes containing two distal loops that are limited to 1 nt each and a central loop up to 30 nt long are likely to form in vitro. This report demonstrates that such structures possessing a long central loop are actually found in the 5′-UTRs of human mRNAs. Firstly, 1453 potential G-quadruplex-forming sequences (PG4s) were identified through a bioinformatic survey that searched for sequences respecting the requirement for two 1-nt long distal loops and a long central loop of 2–90 nt in length. Secondly, in vitro in-line probing experiments confirmed and characterized the folding of eight candidates possessing central loops of 10–70 nt long. Finally, the biological effect of several G-quadruplexes with a long central loop on mRNA expression was studied in cellulo using a luciferase gene reporter assay. Clearly, the actual definition of G-quadruplex-forming sequences is too conservative and must be expanded to include the long central loop. This greatly expands the number of expected PG4s in the transcriptome. Consideration of these new candidates might aid in elucidating the potentially important biological implications of the G-quadruplex structure
    • …
    corecore