464 research outputs found

    Topology optimization of piezo modal transducers with null-polarity phases

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    Second international diagnostic accuracy study for the serological detection of west nile virus infection.

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    Background: In recent decades, sporadic cases and outbreaks in humans of West Nile virus (WNV) infection have increased. Serological diagnosis of WNV infection can be performed by enzyme-linked immunosorbent assay (ELISA), immunoflu- orescence assay (IFA) neutralization test (NT) and by hemagglutination-inhibition assay. The aim of this study is to collect updated information regarding the performance accuracy of WNV serological diagnostics. Methodology/Principal findings: In 2011, the European Network for the Diagnostics of Imported Viral Diseases- Collaborative Laboratory Response Network (ENIVD-CLRN) organized the second external quality assurance (EQA) study for the serological diagnosis of WNV infection. A serum panel of 13 samples (included sera reactive against WNV, plus specificity and negative controls) was sent to 48 laboratories involved in WNV diagnostics. Forty-seven of 48 laboratories from 30 countries participated in the study. Eight laboratories achieved 100% of concurrent and correct results. The main obstacle in other laboratories to achieving similar performances was the cross-reactivity of antibodies amongst heterologous flaviviruses. No differences were observed in performances of in-house and commercial test used by the laboratories. IFA was significantly more specific compared to ELISA in detecting IgG antibodies. The overall analytical sensitivity and specificity of diagnostic tests for IgM detection were 50% and 95%, respectively. In comparison, the overall sensitivity and specificity of diagnostic tests for IgG detection were 86% and 69%, respectively. Conclusions/Significance: This EQA study demonstrates that there is still need to improve serological tests for WNV diagnosis. The low sensitivity of IgM detection suggests that there is a risk of overlooking WNV acute infections, whereas the low specificity for IgG detection demonstrates a high level of cross-reactivity with heterologous flaviviruse

    La onomástica de nombres erróneos en la construcción de andinidad fallida y débil andeancia: el imperativo de microrefugios bioculturales en los Andes

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    We seek to (re)construct a geocritical narrative for the essence of place, by (re)writing mountain specificities that imprint cultural traits on tropical and temperate Andean landscapes, creating a unique identity trilemma for the people of highland South America. We use onomastics as a study of mistaken individuality, with a poststructuralism approach to define ‘the Andean’ within humanistic geoecology; thus, we incorporate notions related to common phenotypic traits of ‘Andeanity’, together with cryptic, emergent properties of ‘Andeaness’ and mystic conditions of spirituality of ‘Andeanitude’, to produce a new trifecta of ecoregional building, with a challenging epistemology for ‘Andean’ as a biocultural heritage landscape informed from traditional knowledge, dialectically appropriated from the old and the young, the foreign and the native, and the original and the composed. Hence, the imagined, heterogeneous, and dynamic identity of Andean people is characterized as dynamic and evolving flow of the mountainscape. We argue that it is still adapting to frameworks of global environment change; hence, it is subjected to withering if not for certain biocultural microrefugia that keep Andean landscape memory alive. With a review of the hermeneutics of Andes, because of orthographic variants (c.f.: graphiosis) that incorporated Kichwa-based, Kañary-based or Mapudungun-based words in the hegemonic lexicon of colonial expansionism of Castilian terms, we argue for the inclusion of vernacular descriptors instead of Roman Sanctorum or Patriotic ephemerides utilized to name geographical features in Andean South America. A plea to restore vernacular descriptors with the original peoples’ language uses, toponymy and onomatopoeia, brings political recognition and invigorates original communities’ pride of their ancestral heritage to reinforce their wellbeing in biodiversity microrefugia. Switching from imperial, imposed names of colonialist geographies to vernacular words or other non-hegemonic locatives of (de) colonial scholarship will help find a better “sense of place” in the Andes and will increase the likelihood of survival and (re)generation of ancestral socio-ecological production Andean mountainscapes.Buscamos (re)construir una narrativa geocrítica para la esencia del paisaje al (re)escribir las especificidades de montaña que impriman atributos culturales en los paisajes andinos tropicales y templados, creando un trilema de identidad único para la gente de las tierras altas de América del Sur. Usamos la onomástica como un estudio de la individualidad errada con un enfoque post-estructuralista para definir “lo andino” dentro de la geoecología humanística; por lo tanto, incorporamos nociones relacionadas con los atributos fenotípicos de Andeanidad, junto con las propiedades crípticas emergentes de Andeancia y las condiciones místicas de espiritualidad de Andeanitud, para producir una nueva trifecta de construcción ecoregional, con una epistemología desafiante para el paisaje patrimonial biocultural basado en el conocimiento tradicional, apropiado dialécticamente de lo viejo a lo nuevo, de lo foráneo a lo nativo y de lo original a lo copiado. Por lo tanto, la dinámica identidad heterogénea imaginada de la gente andina está caracterizada por un flujo dinámico y evolutivo del paisaje montano. Argumentamos que la nomenclatura aún se adapta a marcos de cambio ambiental global; así, está aún sujeta a deterioro a no ser que ciertos microrefugios bioculturales puedan mantener la memoria del paisaje andino vivo. Con una revisión de la hermenéutica de Andes, debido a las variantes (c.f. grafiosis) que incorporaron palabras basadas en Kichwa, Kañary o Mapudungun en el léxico hegemónico del expansionismo colonial de los términos castellanos, apelamos a la inclusión de los descriptores vernáculos en vez del santoral romano y la efemérides patriótica utilizada para nombrar los atributos geográficos en la Sudamérica andina. Pedimos restaurar los descriptores vernáculos con el lenguaje usado por los pueblos originarios, su toponimia y onomatopeya, para atraer el reconocimiento político y para vigorizar el orgullo del patrimonio ancestral de las comunidades de montaña para refuerzo de su bienestar en los microrefugios bioculturales. Al cambiar los nombres impuestos por la geografía imperial colonial a las palabras vernáculas u otros locativos no hegemónicos de escolaridad decolonial, se ayudará a obtener un mejor ‘sentido del lugar’ en los Andes e incrementará la posibilidad de (super)vivencia y (re)generación de los paisajes productivos socioecológicos ancestrales andinos

    ABA biosynthesis- and signaling-related gene expression differences between sweet cherry fruits suggest attenuation of ABA pathway in bicolored cultivars

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    Fruit development involves exocarp color evolution. However, signals that control this process are still elusive. Differences between dark-red and bicolored sweet cherry cultivars rely on MYB factor gene mutations. Color evolution in bicolored fruits only occurs on the face receiving sunlight, suggesting the perception or response to color-inducing signals is affected. These color differences may be related to synthesis, perception or response to abscisic acid (ABA), a phytohormone responsible for non-climacteric fruit coloring. This work aimed to determine the involvement of ABA in the coloring process of color-contrasting varieties. Several phenolic accumulation patterns differed between bicolored ‘Royal Rainier’ and dark-red ‘Lapins’. Transcript abundance of ABA biosynthetic genes (PavPSY, PavZEP and PavNCED1) decreased dramatically from the Pink to Red stage in ‘Royal Rainier’ but increased in ‘Lapins’, which correlated with a higher ABA content in this dark-red cultivar. Transcripts coding for ABA signaling (PavPP2Cs, PavSnRKs and PavMYB44.1) were almost undetectable at the Red stage in ‘Royal Rainier’. Field trials revealed that ‘Royal Rainier’ color development was insensitive to exogenous ABA, whereas it increased in ‘Lapins’. Furthermore, ABA treatment only increased transcript levels of signaling genes in ‘Lapins’. Further studies may address if the ABA pathway is attenuated in bicolor cultivar

    Rapid ant community reassembly in a Neotropical forest: Recovery dynamics and land‐use legacy

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    Regrowing secondary forests dominate tropical regions today, and a mechanistic understanding of their recovery dynamics provides important insights for conservation. In particular, land‐use legacy effects on the fauna have rarely been investigated. One of the most ecologically dominant and functionally important animal groups in tropical forests are the ants. Here, we investigated the recovery of ant communities in a forest–agricultural habitat mosaic in the Ecuadorian Chocó region. We used a replicated chronosequence of previously used cacao plantations and pastures with 1–34 years of regeneration time to study the recovery dynamics of species communities and functional diversity across the two land‐use legacies. We compared two independent components of responses on these community properties: resistance, which is measured as the proportion of an initial property that remains following the disturbance; and resilience, which is the rate of recovery relative to its loss. We found that compositional and trait structure similarity to old‐growth forest communities increased with regeneration age, whereas ant species richness remained always at a high level along the chronosequence. Land‐use legacies influenced species composition, with former cacao plantations showing higher resemblance to old‐growth forests than former pastures along the chronosequence. While resistance was low for species composition and high for species richness and traits, all community properties had similarly high resilience. In essence, our results show that ant communities of the Chocó recovery rapidly, with former cacao reaching predicted old‐growth forest community levels after 21 years and pastures after 29 years. Recovery in this community was faster than reported from other ecosystems and was likely facilitated by the low‐intensity farming in agricultural sites and their proximity to old‐growth forest remnants. Our study indicates the great recovery potential for this otherwise highly threatened biodiversity hotspot

    Wigner's quantum phase space current in weakly anharmonic weakly excited two-state systems

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    This is an open access article distributed under the terms of the Creative Commons Attribution License CC BY 4.0 (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.There are no phase-space trajectories for anharmonic quantum systems, but Wigner’s phase-space representation of quantum mechanics features Wigner current J . This current reveals fine details of quantum dynamics – finer than is ordinarily thought accessible according to quantum folklore invoking Heisenberg’s uncertainty principle. Here, we focus on the simplest, most intuitive, and analytically accessible aspects of J . We investigate features of J for bound states of time-reversible, weakly-anharmonic one-dimensional quantum-mechanical systems which are weakly-excited. We establish that weakly-anharmonic potentials can be grouped into three distinct classes: hard, soft, and odd potentials. We stress connections between each other and the harmonic case. We show that their Wigner current fieldline patterns can be characterised by J ’s discrete stagnation points, how these arise and how a quantum system’s dynamics is constrained by the stagnation points’ topological charge conservation. We additionally show that quantum dynamics in phase space, in the case of vanishing Planck constant ̄ h or vanishing anharmonicity, does not pointwise converge to classical dynamics.Peer reviewe

    2nd International External Quality Control Assessment for the Molecular Diagnosis of Dengue Infections

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    Dengue viruses (DENV) are the most widespread arthropod-borne viruses which have shown an unexpected geographic expansion, as well as an increase in the number and severity of outbreaks in the last decades. In this context, the accurate diagnosis and reliable surveillance of dengue infections are essential. The laboratory diagnosis of dengue relies on the use of several methods detecting markers of DENV infection present in patient serum. Molecular diagnosis methods are usually rapid, sensitive, and simple when correctly standardized. Moreover, PCR-based diagnosis techniques are able to readily detect DENV during the acute phase of the disease and may assume an important role in dengue diagnosis and surveillance. Different reverse transcriptase PCR (RT-PCR) methods have been developed and are currently available and should be standardized in each laboratory to maintain high quality performance. In this work an External quality assessment (EQA) activity has been carried out to evaluate the accuracy and quality of laboratory data for the molecular diagnosis and surveillance of dengue, which involved worldwide dengue reference laboratories. In conclusion, RT-PCR techniques for dengue diagnosis applied by the participating laboratories demonstrated the need of further improvement in most laboratories
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