80,289 research outputs found

    Bringing together emerging and endemic zoonoses surveillance: shared challenges and a common solution

    Get PDF
    Early detection of disease outbreaks in human and animal populations is crucial to the effective surveillance of emerging infectious diseases. However, there are marked geographical disparities in capacity for early detection of outbreaks, which limit the effectiveness of global surveillance strategies. Linking surveillance approaches for emerging and neglected endemic zoonoses, with a renewed focus on existing disease problems in developing countries, has the potential to overcome several limitations and to achieve additional health benefits. Poor reporting is a major constraint to the surveillance of both emerging and endemic zoonoses, and several important barriers to reporting can be identified: (i) a lack of tangible benefits when reports are made; (ii) a lack of capacity to enforce regulations; (iii) poor communication among communities, institutions and sectors; and (iv) complexities of the international regulatory environment. Redirecting surveillance efforts to focus on endemic zoonoses in developing countries offers a pragmatic approach that overcomes some of these barriers and provides support in regions where surveillance capacity is currently weakest. In addition, this approach addresses immediate health and development problems, and provides an equitable and sustainable mechanism for building the culture of surveillance and the core capacities that are needed for all zoonotic pathogens, including emerging disease threats

    Exposure of a 23F serotype strain of <i>Streptococcus pneumoniae</i> to cigarette smoke condensate is associated with selective upregulation of genes encoding the two-component regulatory system 11 (TCS11)

    Get PDF
    Alterations in whole genome expression profiles following exposure of the pneumococcus (strain 172, serotype 23F) to cigarette smoke condensate (160 μg/mL) for 15 and 60 min have been determined using the TIGR4 DNA microarray chip. Exposure to CSC resulted in the significant (P &#60; 0.014–0.0006) upregulation of the genes encoding the two-component regulatory system 11 (TCS11), consisting of the sensor kinase, hk11, and its cognate response regulator, rr11, in the setting of increased biofilm formation. These effects of cigarette smoke on the pneumococcus may contribute to colonization of the airways by this microbial pathogen

    Distinct expression and methylation patterns for genes with different fates following a single whole-genome duplication in flowering plants

    Get PDF
    For most sequenced flowering plants, multiple whole-genome duplications (WGDs) are found. Duplicated genes following WGD often have different fates that can quickly disappear again, be retained for long(er) periods, or subsequently undergo small-scale duplications. However, how different expression, epigenetic regulation, and functional constraints are associated with these different gene fates following a WGD still requires further investigation due to successive WGDs in angiosperms complicating the gene trajectories. In this study, we investigate lotus (Nelumbo nucifera), an angiosperm with a single WGD during the K–pg boundary. Based on improved intraspecific-synteny identification by a chromosome-level assembly, transcriptome, and bisulfite sequencing, we explore not only the fundamental distinctions in genomic features, expression, and methylation patterns of genes with different fates after a WGD but also the factors that shape post-WGD expression divergence and expression bias between duplicates. We found that after a WGD genes that returned to single copies show the highest levels and breadth of expression, gene body methylation, and intron numbers, whereas the long-retained duplicates exhibit the highest degrees of protein–protein interactions and protein lengths and the lowest methylation in gene flanking regions. For those long-retained duplicate pairs, the degree of expression divergence correlates with their sequence divergence, degree in protein–protein interactions, and expression level, whereas their biases in expression level reflecting subgenome dominance are associated with the bias of subgenome fractionation. Overall, our study on the paleopolyploid nature of lotus highlights the impact of different functional constraints on gene fate and duplicate divergence following a single WGD in plant

    Multigene phylogeny and mating tests reveal three cryptic species related to Calonectria pauciramosa

    Get PDF
    Calonectria pauciramosa is a pathogen of numerous plant hosts worldwide. Recent studies have indicated that it included cryptic species, some of which are identified in this study. Isolates from various geographical origins were collected and compared based on morphology, DNA sequence data of the ß-tubulin, histone H3 and translation elongation factor-1 regions and mating compatibility. Comparisons of the DNA sequence data and mating compatibility revealed three new species. These included Ca. colombiana sp. nov. from Colombia, Ca. polizzii sp. nov. from Italy and Ca. zuluensis sp. nov. from South Africa, all of which had distinguishing morphological features. Based on DNA sequence data, Ca. brasiliensis is also elevated to species leve

    The Classification of Real Singularities Using SINGULAR. Part I: Splitting Lemma and Simple Singularities

    Get PDF
    We present algorithms to classify isolated hypersurface singularities over the real numbers according to the classification by V.I. Arnold (Arnold et al., 1985). This first part covers the splitting lemma and the simple singularities; a second and a third part will be devoted to the unimodal singularities up to corank 2. All algorithms are implemented in the SINGULAR library realclassify.lib (Marais and Steenpass, 2012).Comment: 12 pages, 1 tabl

    Strong Klee-And\^o Theorems through an Open Mapping Theorem for cone-valued multi-functions

    Get PDF
    A version of the classical Klee-And\^o Theorem states the following: For every Banach space XX, ordered by a closed generating cone CXC\subseteq X, there exists some α>0\alpha>0 so that, for every xXx\in X, there exist x±Cx^{\pm}\in C so that x=x+xx=x^{+}-x^{-} and x++xαx\|x^{+}\|+\|x^{-}\|\leq\alpha\|x\|. The conclusion of the Klee-And\^o Theorem is what is known as a conormality property. We prove stronger and somewhat more general versions of the Klee-And\^o Theorem for both conormality and coadditivity (a property that is intimately related to conormality). A corollary to our result shows that the functions xx±x\mapsto x^{\pm}, as above, may be chosen to be bounded, continuous, and positively homogeneous, with a similar conclusion yielded for coadditivity. Furthermore, we show that the Klee-And\^o Theorem generalizes beyond ordered Banach spaces to Banach spaces endowed with arbitrary collections of cones. Proofs of our Klee-And\^o Theorems are achieved through an Open Mapping Theorem for cone-valued multi-functions/correspondences. We very briefly discuss a potential further strengthening of The Klee-And\^o Theorem beyond what is proven in this paper, and motivate a conjecture that there exists a Banach space XX, ordered by a closed generating cone CXC\subseteq X, for which there exist no Lipschitz functions ()±:XC(\cdot)^{\pm}:X\to C satisfying x=x+xx=x^{+}-x^{-} for all xXx\in X.Comment: Major rewrite. Large parts were removed which a referee pointed out can be proven through much easier method

    Making stillbirths count, making numbers talk - issues in data collection for stillbirths.

    Get PDF
    BACKGROUND: Stillbirths need to count. They constitute the majority of the world's perinatal deaths and yet, they are largely invisible. Simply counting stillbirths is only the first step in analysis and prevention. From a public health perspective, there is a need for information on timing and circumstances of death, associated conditions and underlying causes, and availability and quality of care. This information will guide efforts to prevent stillbirths and improve quality of care. DISCUSSION: In this report, we assess how different definitions and limits in registration affect data capture, and we discuss the specific challenges of stillbirth registration, with emphasis on implementation. We identify what data need to be captured, we suggest a dataset to cover core needs in registration and analysis of the different categories of stillbirths with causes and quality indicators, and we illustrate the experience in stillbirth registration from different cultural settings. Finally, we point out gaps that need attention in the International Classification of Diseases and review the qualities of alternative systems that have been tested in low- and middle-income settings. SUMMARY: Obtaining high-quality data will require consistent definitions for stillbirths, systematic population-based registration, better tools for surveys and verbal autopsies, capacity building and training in procedures to identify causes of death, locally adapted quality indicators, improved classification systems, and effective registration and reporting systems

    Event-centrality and the pragmatics-semantics interface in Kikongo : from predication focus to progressive aspect and vice versa

    Get PDF
    Across Bantu, several polysemic markers expressing progressive aspect and so-called predication focus have been reported (Güldemann 2003; Hyman and Watters 1984). In this article, we examine two such markers in Kikongo (Bantu, H16), i.e. the fronted-infinitive and the locative-infinitive constructions. We provide an in-depth synchronic description of the pragmatic and syntactic behaviour of both verbal constructions and suggest a historical evolution for each of them. We evoke the term ‘event-centrality’ to cover the different uses of both constructions and suggest that the fronted-infinitive construction’s progressive meaning evolved from its use as predication focus marker, and vice versa, that the locative-infinitive construction’s predication focus meaning evolved from its use as a progressive marker

    Time-varying persistence in US inflation

    Get PDF
    The persistence property of inflation is an important issue not only for economists, but especially for central banks, given that the degree of inflation persistence determines the extent to which central banks can control inflation. Further, not only is it the level of inflation persistence that is important in economic analyses, but also the question of whether the persistence varies over time, for instance, across business cycle phases, is equally pertinent, since assuming constant persistence across states of the economy is sure to lead to misguided policy decisions. Against this backdrop, we extend the literature on long-memory models of inflation persistence for the US economy over the monthly period of 1920:1\u20132014:5, by developing an autoregressive fractionally integrated moving-average-generalized autoregressive conditional heteroskedastic model with a time-varying memory coefficient which varies across expansions and recessions. In sum, we find that inflation persistence does vary across recessions and expansions, with it being significantly higher in the former than in the latter. As an aside, we also show that persistence of inflation volatility is higher during expansions than in recessions. Understandably, our results have important policy implications

    Entanglement and the Quantum Brachistochrone Problem

    Get PDF
    Entanglement is closely related to some fundamental features of the dynamics of composite quantum systems: quantum entanglement enhances the "speed" of evolution of certain quantum states, as measured by the time required to reach an orthogonal state. The concept of "speed" of quantum evolution constitutes an important ingredient in any attempt to determine the fundamental limits that basic physical laws impose on how fast a physical system can process or transmit information. Here we explore the relationship between entanglement and the speed of quantum evolution in the context of the quantum brachistochrone problem. Given an initial and a final state of a composite system we consider the amount of entanglement associated with the brachistochrone evolution between those states, showing that entanglement is an essential resource to achieve the alluded time-optimal quantum evolution.Comment: 6 pages, 3 figures. Corrected typos in Eqs. 1 and
    corecore