1,361 research outputs found

    Primeras citas fidedignas del género Aceria Asociado a Quercus ilex L. y Q. coccifera L. para el nordeste de la Península Ibérica.

    Get PDF
    Se realizĂł la determinaciĂłn taxonĂłmica de ejemplares adultos de ĂĄcaros eriĂłfidos obtenidos de dos erineos de hojas de Quercus ilex y Q. coccifera. Se cita Aceria ilicis (Canestrini, 1890) en Quercus ilex y Q. coccifera, y Aceria trichophila Keifer, 1955 en Q. ilex. Ambas especies fueron colectadas en el Parque Natural de Collserola (Barcelona, Cataluña). Se reporta a A. trichophila por primera vez en el PaleĂĄrtico y por primera vez sobre Q. ilex. Se confirma la presencia de A. ilicis en el noreste ibĂ©rico, especie ampliamente citada con presencia en la PenĂ­nsula IbĂ©rica a partir Ășnicamente de los erineos colectados

    Biofortification with magnesium nanofertilizer on bioactive compounds and antioxidant capacity in green beans

    Get PDF
    The use of nanofertilizers has the potential to be used to enrich edible organs with nutrients (biofortification) and improve the biosynthesis of bioactive compounds and their antioxidant capacity. Therefore, the objective of this study was to evaluate the effect of biofortification with magnesium (Mg) nanofertilizer on the accumulation of bioactive compounds and antioxidant capacity in green bean cv. Strike compared to a conventional fertilizer (Mg sulfate). Two sources of Mg were applied via foliar: Nanofertilizer and Mg Sulfate at doses of 0, 50, 100, 200, and 300 mg/L of Mg. The accumulation of total polyphenols, flavonoids, anthocyanins, bioactive compounds, and antioxidant capacity was evaluated in pods. The results obtained in this research confirm the effect of green bean pods biofortified with Mg nanofertilizers on the production and accumulation of bioactive compounds and antioxidant capacity, improving the nutrition and nutraceutical quality of green beans. The 50 mg/L dose of Mg nanofertilizer was the most effective treatment to increase bioactive compounds and antioxidant capacity compared to high doses of Mg sulfate (300 mg/L). This is one of the first studies focused on biofortification with Mg nanofertilizers and their effect on the nutraceutical quality of green beans

    Evolution and spread of Venezuelan equine encephalitis complex alphavirus in the Americas.

    Get PDF
    Venezuelan equine encephalitis (VEE) complex alphaviruses are important re-emerging arboviruses that cause life-threatening disease in equids during epizootics as well as spillover human infections. We conducted a comprehensive analysis of VEE complex alphaviruses by sequencing the genomes of 94 strains and performing phylogenetic analyses of 130 isolates using complete open reading frames for the nonstructural and structural polyproteins. Our analyses confirmed purifying selection as a major mechanism influencing the evolution of these viruses as well as a confounding factor in molecular clock dating of ancestors. Times to most recent common ancestors (tMRCAs) could be robustly estimated only for the more recently diverged subtypes; the tMRCA of the ID/IAB/IC/II and IE clades of VEE virus (VEEV) were estimated at ca. 149–973 years ago. Evolution of the IE subtype has been characterized by a significant evolutionary shift from the rest of the VEEV complex, with an increase in structural protein substitutions that are unique to this group, possibly reflecting adaptation to its unique enzootic mosquito vector Culex (Melanoconion) taeniopus. Our inferred tree topologies suggest that VEEV is maintained primarily in situ, with only occasional spread to neighboring countries, probably reflecting the limited mobility of rodent hosts and mosquito vectors

    La alfabetizaciĂłn matemĂĄtica y su relaciĂłn con el intercambio comercial, la escolaridad elemental y el trabajo

    Get PDF
    En este artĂ­culo abordo algunos aspectos de la adquisiciĂłn del conocimiento y las herramientas matemĂĄticas elementales en diferentes contextos: la educaciĂłn bĂĄsica de personas jĂłvenes y adultas, algunas actividades laborales que no requieren una escolaridad importante, y la experiencia de intercambio comercial que se desarrolla en la cotidianeidad. Mi intenciĂłn es contribuir a la reflexiĂłn sobre los aportes de la educaciĂłn bĂĄsica, la experiencia cotidiana y el trabajo a la alfabetizaciĂłn matemĂĄtica de las personas. Para ilustrar mis afirmaciones, tomo como centro la nociĂłn de proporcionalidad. Esta nociĂłn cruza la educaciĂłn bĂĄsica, es fundamento de la matemĂĄtica mĂĄs avanzada y, tambiĂ©n, es instrumento de trabajo e interacciĂłn en distintos ĂĄmbitos de la actividad social. Adelanto que, en MĂ©xico, el sistema educativo para jĂłvenes y adultos incumple en buena medida un compromiso fundamental: lograr que las personas se apropien de herramientas simbĂłlicas que potencien su pensamiento y su forma de vinculaciĂłn con el mundo. En cambio, algunas actividades laborales y comerciales contribuyen al desarrollo de conocimientos y habilidades Ăștiles para resolver problemas matemĂĄticos que el propio contexto plantea. Este tipo de aprendizaje, no debe empero olvidarse, es un aprendizaje situado cuyos lĂ­mites conviene tambiĂ©n señalar

    Clinical Prediction Rule for Stratifying Risk of Pulmonary Multidrug-Resistant Tuberculosis

    Get PDF
    Multidrug-resistant tuberculosis (MDR-TB), resistance to at least isoniazid and rifampin, is a worldwide problem.To develop a clinical prediction rule to stratify risk for MDR-TB among patients with pulmonary tuberculosis.Derivation and internal validation of the rule among adult patients prospectively recruited from 37 health centers (PerĂș), either a) presenting with a positive acid-fast bacillus smear, or b) had failed therapy or had a relapse within the first 12 months.Among 964 patients, 82 had MDR-TB (prevalence, 8.5%). Variables included were MDR-TB contact within the family, previous tuberculosis, cavitary radiologic pattern, and abnormal lung exam. The area under the receiver-operating curve (AUROC) was 0.76. Selecting a cut-off score of one or greater resulted in a sensitivity of 72.6%, specificity of 62.8%, likelihood ratio (LR) positive of 1.95, and LR negative of 0.44. Similarly, selecting a cut-off score of two or greater resulted in a sensitivity of 60.8%, specificity of 87.5%, LR positive of 4.85, and LR negative of 0.45. Finally, selecting a cut-off score of three or greater resulted in a sensitivity of 45.1%, specificity of 95.3%, LR positive of 9.56, and LR negative of 0.58.A simple clinical prediction rule at presentation can stratify risk for MDR-TB. If further validated, the rule could be used for management decisions in resource-limited areas

    Shape - but Not Size - Codivergence between Male and Female Copulatory Structures in Onthophagus Beetles

    Get PDF
    Genitalia are among the fastest evolving morphological traits in arthropods. Among the many hypotheses aimed at explaining this observation, some explicitly or implicitly predict concomitant male and female changes of genital traits that interact during copulation (i.e., lock and key, sexual conflict, cryptic female choice and pleiotropy). Testing these hypotheses requires insights into whether male and female copulatory structures that physically interact during mating also affect each other's evolution and patterns of diversification. Here we compare and contrast size and shape evolution of male and female structures that are known to interact tightly during copulation using two model systems: (a) the sister species O. taurus (1 native, 3 recently established populations) and O. illyricus, and (b) the species-complex O. fracticornis-similis-opacicollis. Partial Least Squares analyses indicated very little to no correlation between size and shape of copulatory structures, both in males and females. Accordingly, comparing shape and size diversification patterns of genitalia within each sex showed that the two components diversify readily - though largely independently of each other - within and between species. Similarly, comparing patterns of divergence across sexes showed that relative sizes of male and female copulatory organs diversify largely independent of each other. However, performing this analysis for genital shape revealed a signature of parallel divergence. Our results therefore suggest that male and female copulatory structures that are linked mechanically during copulation may diverge in concert with respect to their shapes. Furthermore, our results suggest that genital divergence in general, and co-divergence of male and female genital shape in particular, can evolve over an extraordinarily short time frame. Results are discussed in the framework of the hypotheses that assume or predict concomitant evolutionary changes in male and female copulatory organs

    A Chemical Analog of Curcumin as an Improved Inhibitor of Amyloid Abeta Oligomerization

    Get PDF
    Amyloid-like plaques are characteristic lesions defining the neuropathology of Alzheimer's disease (AD). The size and density of these plaques are closely associated with cognitive decline. To combat this disease, the few therapies that are available rely on drugs that increase neurotransmission; however, this approach has had limited success as it has simply slowed an imminent decline and failed to target the root cause of AD. Amyloid-like deposits result from aggregation of the AÎČ peptide, and thus, reducing amyloid burden by preventing AÎČ aggregation represents an attractive approach to improve the therapeutic arsenal for AD. Recent studies have shown that the natural product curcumin is capable of crossing the blood-brain barrier in the CNS in sufficient quantities so as to reduce amyloid plaque burden. Based upon this bioactivity, we hypothesized that curcumin presents molecular features that make it an excellent lead compound for the development of more effective inhibitors of AÎČ aggregation. To explore this hypothesis, we screened a library of curcumin analogs and identified structural features that contribute to the anti-oligomerization activity of curcumin and its analogs. First, at least one enone group in the spacer between aryl rings is necessary for measureable anti-AÎČ aggregation activity. Second, an unsaturated carbon spacer between aryl rings is essential for inhibitory activity, as none of the saturated carbon spacers showed any margin of improvement over that of native curcumin. Third, methoxyl and hydroxyl substitutions in the meta- and para-positions on the aryl rings appear necessary for some measure of improved inhibitory activity. The best lead inhibitors have either their meta- and para-substituted methoxyl and hydroxyl groups reversed from that of curcumin or methoxyl or hydroxyl groups placed in both positions. The simple substitution of the para-hydroxy group on curcumin with a methoxy substitution improved inhibitor function by 6-7-fold over that measured for curcumin

    Search for a vector-like quark Tâ€Č → tH via the diphoton decay mode of the Higgs boson in proton-proton collisions at s \sqrt{s} = 13 TeV

    Get PDF
    A search for the electroweak production of a vector-like quark Tâ€Č, decaying to a top quark and a Higgs boson is presented. The search is based on a sample of proton-proton collision events recorded at the LHC at = 13 TeV, corresponding to an integrated luminosity of 138 fb−1. This is the first Tâ€Č search that exploits the Higgs boson decay to a pair of photons. For narrow isospin singlet Tâ€Č states with masses up to 1.1 TeV, the excellent diphoton invariant mass resolution of 1–2% results in an increased sensitivity compared to previous searches based on the same production mechanism. The electroweak production of a Tâ€Č quark with mass up to 960 GeV is excluded at 95% confidence level, assuming a coupling strength ÎșT = 0.25 and a relative decay width Γ/MTâ€Č < 5%
    • 

    corecore