Imidacloprid decreases honey bee survival rates but does not affect the gut microbiome

Accumulating evidence suggests that pesticides have played a role in the increased rate of honey bee colony loss. One of the most commonly used pesticides in the United States is the neonicotinoid imidacloprid. Although the primary mode of action of imidacloprid is on the insect nervous system, it has also been shown to cause changes in insects' digestive physiology and alter the microbiota of Drosophila melanogaster larvae. The honey bee gut microbiome plays a major role in bee health. Although many studies have shown that imidacloprid affects honey bee behavior, its impact on the microbiome has not been fully elucidated. Here, we investigated the impact of imidacloprid on the gut microbiome composition, survivorship, and susceptibility to pathogens of honey bees. Consistent with other studies, we show that imidacloprid exposure results in an elevated mortality of honey bees in the hive and increases the susceptibility to infection by pathogens. However, we did not find evidence that imidacloprid affects the gut bacterial community of honey bees. Our in vitro experiments demonstrated that honey bee gut bacteria can grow in the presence of imidacloprid, and we found some evidence that imidacloprid can be metabolized in the bee gut environment. However, none of the individual bee gut bacterial species tested could metabolize imidacloprid, suggesting that the observed metabolism of imidacloprid within in vitro bee gut cultures is not caused by the gut bacteria. Overall, our results indicate that imidacloprid causes increased mortality in honey bees, but this mortality does not appear to be linked to the microbiome

Development and Validation of a Sensitive UFLC–MS/MS Method for Quantification of Quercitrin in Plasma: Application to a Tissue Distribution Study

Quercitrin, a glycosylated form of the flavonoid quercetin, is one of the major constituents of Copaifera langsdorffii leaves and potentially contributes to the medicinal properties reported for this plant species, including the treatment and prevention of kidney stones. To better understand the pharmacokinetics of quercitrin, a simple, rapid, and sensitive ultra fast liquid chromatography−tandem mass spectrometry method was developed and validated for the quantification of quercitrin in rat plasma and applied to a tissue distribution study. Sample preparation involved simple liquid−liquid extraction by ethyl acetate with high efficiency, using afzelin as internal standard. The chromatographic separation was performed on a Phenomenex Synergi Polar-RP (100 × 3.0 mm2, 2.5 μm), with a gradient elution of acetonitrile and 0.5% formic acid in water. The mass spectrometry analysis was conducted in negative ionization mode with multiple reaction monitoring transitions at m/z 447 → 300 for quercitrin and m/z 431 → 281 for afzelin. The method showed linearity in the concentration range of 5−100 ng/mL (r2 > 0.9959) and the lower limit of quantification was 5 ng/mL. The intraday and interday precision (relative standard deviation) were less than 10.73%, whereas the accuracy ranged from 81.4 to 111.0%. The extraction recovery, stability, matrix effect, and integrity dilution involved in the method were also validated. In addition, tissue distribution was assessed after an intravenous administration of 1 mg/kg quercitrin. This is the first report quantifying quercitrin in kidneys, demonstrating that the free tissue/plasma ratio was 23.7

Primer congreso científico UNACHI 2015.

La Universidad Autónoma de Chiriquí (UNACHI), a través de la Vicerrectoría de Investigación y Postgrado (VIP), en cumplimiento de su misión, visión y objetivos estratégicos, realiza el Primer Congreso Científico del 5 al 9 de octubre de 2015, con el lema: “Impulsando la cultura, la ciencia y la humanidad”. En atención al Plan Estratégico del Gobierno de la República de Panamá 2015-2019; al Plan Estratégico Nacional de Ciencia, Tecnología e Innovación (PENCYT) 2015-2019 de la Secretaría Nacional de Ciencia, Tecnología e Innovación (SENACYT); al Plan Estratégico Institucional 2013-2018 de la Universidad Autónoma de Chiriquí y a las Políticas de Investigación e Innovación de la Universidad, se presenta a la consideración de la comunidad científica universitaria y a la sociedad panameña, los resultados de las investigaciones correspondientes al período académico 2014-2015. Las investigaciones que hoy se presentan, corresponden a trabajos realizados por investigadores procedentes de nuestra institución, de universidades y centros de investigación del país y de investigadores procedentes de países hermanos, quienes comparten con nosotros los productos de sus muchas horas de trabajo realizadas en sus laboratorios, redes temáticas y giras de campo. El Congreso tiene sus antecedentes en los seis encuentros científicos realizados, anualmente en la universidad, desde el año 2009 hasta el año 2014. No obstante, dado el impulso y decidido respaldo de la Magnífica Rectora, Etelvina Medianero de Bonagas, al eje de investigación e innovación y al trabajo realizado por nuestros investigadores, se presentó ante el Consejo Académico N° 11-2015, del 16 de junio de 2015, la propuesta para elevar los encuentros a congreso científico, y que fue aprobada por unanimidad. Se convierte este evento académico, en un reto para la institución y a la vez en una gran oportunidad para el fortalecimiento de la investigación e innovación, al servicio de la sociedad y de los grandes temas de interés nacional. Con mucho agrado se puede señalar que en el Congreso se exponen conferencias magistrales, conferencias cortas, ponencias, mesas redondas, videoconferencias y dos exposiciones fotográficas tituladas: “Nuestros ríos, nuestro futuro” y “La luz en las ciencias”. Por segundo año consecutivo se realiza el reconocimiento al investigador del año; en esta oportunidad se honrará al connotado ambientalista Demetrio Miranda Miranda. Se presentan investigadores nacionales de la Secretaría Nacional de Ciencia, Tecnología e Innovación; de la Universidad Tecnológica de Panamá; del Instituto de Investigaciones Científicas y Servicios de Alta Tecnología; de la Universidad de Panamá; del Ministerio de Salud y de la Universidad Autónoma de Chiriquí. También se cuenta con investigadores internacionales procedentes de Estados Unidos, Honduras, Costa Rica y de República Dominicana. Los registros de los participantes, en la página web de la universidad, nos indican que durante el congreso se tendrá la participación de investigadores procedentes de las áreas de las ciencias económicas administrativas, de las ciencias de la salud, de las ciencias sociales y humanidades y de las ciencias naturales y exactas, estos últimos en un mayor porcentaje. Atendiendo a sus políticas institucionales, la UNACHI está cimentando las bases de un sistema de investigación e innovación, a través de acciones muy puntuales, las cuales aspiran a convertir a la Institución, en un centro de educación superior de excelencia y a disponer de un conjunto de investigadores de alto nivel. Con este propósito, se ha aprobado en el Consejo Académico, el Reglamento de Investigación e Innovación, donde se establece por primera vez, la figura del investigador a tiempo completo, a fin de impulsar la investigación en todas las áreas del conocimiento humano; se ha firmado un convenio con SENACYT para la reinserción de talentos en el nivel doctoral, a partir del año 2015, con miras a fortalecer la investigación científica y se han incrementado, significativamente, los fondos destinados a los subsidios de las investigaciones de las tesis de licenciatura, de las tesis de maestrías, de las tesis de doctorados y de los docentes investigadores, con proyectos que se encuentran en este momento en revisión por los evaluadores externos

Nonresonant central exclusive production of charged-hadron pairs in proton-proton collisions at s\sqrt{s} = 13 TeV

International audienceThe central exclusive production of charged-hadron pairs in pp collisions at a centre-of-mass energy of 13\TeV is examined, based on data collected in a special high-$\beta^*$ run of the LHC. The nonresonant continuum processes are studied with the invariant mass of the centrally produced two-pion system in the resonance-free region, $m_{\pi^+\pi^-}$$\lt$ 0.7 GeV or $m_{\pi^+\pi^-}$$\gt$ 1.8 GeV. Differential cross sections as functions of the azimuthal angle between the surviving protons, squared exchanged four-momenta, and $m_{\pi^+\pi^-}$ are measured in a wide region of scattered proton transverse momenta, between 0.2 and 0.8 GeV, and for pion rapidities $\lvert y\rvert$$\lt$ 2. A rich structure of interactions related to double-pomeron exchange is observed. A parabolic minimum in the distribution of the two-proton azimuthal angle is observed for the first time. It can be interpreted as an effect of additional pomeron exchanges between the protons from the interference between the bare and the rescattered amplitudes. After model tuning, various physical quantities are determined that are related to the pomeron cross section, proton-pomeron and meson-pomeron form factors, pomeron trajectory and intercept, and coefficients of diffractive eigenstates of the proton

Nonresonant central exclusive production of charged-hadron pairs in proton-proton collisions at s\sqrt{s} = 13 TeV

International audienceThe central exclusive production of charged-hadron pairs in pp collisions at a centre-of-mass energy of 13\TeV is examined, based on data collected in a special high-$\beta^*$ run of the LHC. The nonresonant continuum processes are studied with the invariant mass of the centrally produced two-pion system in the resonance-free region, $m_{\pi^+\pi^-}$$\lt$ 0.7 GeV or $m_{\pi^+\pi^-}$$\gt$ 1.8 GeV. Differential cross sections as functions of the azimuthal angle between the surviving protons, squared exchanged four-momenta, and $m_{\pi^+\pi^-}$ are measured in a wide region of scattered proton transverse momenta, between 0.2 and 0.8 GeV, and for pion rapidities $\lvert y\rvert$$\lt$ 2. A rich structure of interactions related to double-pomeron exchange is observed. A parabolic minimum in the distribution of the two-proton azimuthal angle is observed for the first time. It can be interpreted as an effect of additional pomeron exchanges between the protons from the interference between the bare and the rescattered amplitudes. After model tuning, various physical quantities are determined that are related to the pomeron cross section, proton-pomeron and meson-pomeron form factors, pomeron trajectory and intercept, and coefficients of diffractive eigenstates of the proton

Observation of the J/ψ→μ+μ−μ+μ− {\mathrm{J}/\psi} \to\mu^{+}\mu^{-}\mu^{+}\mu^{-} decay in proton-proton collisions at s= \sqrt{s} = 13 TeV

The ${\mathrm{J}/\psi} \to\mu^{+}\mu^{-}\mu^{+}\mu^{-}$ decay has been observed with a statistical significance in excess of five standard deviations. The analysis is based on an event sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 33.6 fb$^{-1}$. Normalizing to the ${\mathrm{J}/\psi} \to\mu^{+}\mu^{-}$ decay mode leads to a branching fraction of $[$ 10.1 $^{+3.3}_{-2.7}$ (stat) $\pm$ 0.4 (syst) $] \times$ 10$^{-7}$, a value that is consistent with the standard model prediction.The J/ψ→μ+μ-μ+μ- decay has been observed with a statistical significance in excess of five standard deviations. The analysis is based on an event sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 33.6  fb-1. Normalizing to the J/ψ→μ+μ- decay mode leads to a branching fraction of [10.1-2.7+3.3(stat)±0.4(syst)]×10-7, a value that is consistent with the standard model prediction.The J/$\psi$$\to$$\mu^+\mu^-\mu^+\mu^-$ decay has been observed with a statistical significance in excess of five standard deviations. The analysis is based on an event sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 33.6 fb$^{-1}$. Normalizing to the J/$\psi$$\to$$\mu^+\mu^-$ decay mode leads to a branching fraction [10.1 $^{+3.3}_{-2.7}$ (stat) $\pm$ 0.4 (syst)] $\times$ 10$^{-7}$, a value that is consistent with the standard model prediction

Search for long-lived particles using displaced vertices and missing transverse momentum in proton-proton collisions at s= \sqrt{s}= 13 TeV

A search for the production of long-lived particles in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC is presented. The search is based on data collected by the CMS experiment in 2016-2018, corresponding to a total integrated luminosity of 137 fb$^{-1}$. This search is designed to be sensitive to long-lived particles with mean proper decay lengths between 0.1 and 1000 mm, whose decay products produce a final state with at least one displaced vertex and missing transverse momentum. A machine learning algorithm, which improves the background rejection power by more than an order of magnitude, is applied to improve the sensitivity. The observation is consistent with the standard model background prediction, and the results are used to constrain split supersymmetry (SUSY) and gauge-mediated SUSY breaking models with different gluino mean proper decay lengths and masses. This search is the first CMS search that shows sensitivity to hadronically decaying long-lived particles from signals with mass differences between the gluino and neutralino below 100 GeV. It sets the most stringent limits to date for split-SUSY models and gauge-mediated SUSY breaking models with gluino proper decay length less than 6 mm.A search for the production of long-lived particles in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC is presented. The search is based on data collected by the CMS experiment in 2016–2018, corresponding to a total integrated luminosity of 137  fb-1. This search is designed to be sensitive to long-lived particles with mean proper decay lengths between 0.1 and 1000 mm, whose decay products produce a final state with at least one displaced vertex and missing transverse momentum. A machine learning algorithm, which improves the background rejection power by more than an order of magnitude, is applied to improve the sensitivity. The observation is consistent with the standard model background prediction, and the results are used to constrain split supersymmetry (SUSY) and gauge-mediated SUSY breaking models with different gluino mean proper decay lengths and masses. This search is the first CMS search that shows sensitivity to hadronically decaying long-lived particles from signals with mass differences between the gluino and neutralino below 100 GeV. It sets the most stringent limits to date for split-SUSY models and gauge-mediated SUSY breaking models with gluino proper decay length less than 6 mm.A search for the production of long-lived particles in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC is presented. The search is based on data collected by the CMS experiment in 2016-2018, corresponding to a total integrated luminosity of 137 fb$^{-1}$. This search is designed to be sensitive to long-lived particles with mean proper decay lengths between 0.1 and 1000 mm, whose decay products produce a final state with at least one displaced vertex and missing transverse momentum. A machine learning algorithm, which improves the background rejection power by more than an order of magnitude, is applied to improve the sensitivity. The observation is consistent with the standard model background prediction, and the results are used to constrain split supersymmetry (SUSY) and gauge-mediated SUSY breaking models with different gluino mean proper decay lengths and masses. This search is the first CMS search that shows sensitivity to hadronically decaying long-lived particles from signals with mass differences between the gluino and neutralino below 100 GeV. It sets the most stringent limits to date for split-SUSY models and gauge-mediated SUSY breaking models with gluino proper decay length less than 6 mm

Nonresonant central exclusive production of charged-hadron pairs in proton-proton collisions at s\sqrt{s} = 13 TeV

International audienceThe central exclusive production of charged-hadron pairs in pp collisions at a centre-of-mass energy of 13\TeV is examined, based on data collected in a special high-$\beta^*$ run of the LHC. The nonresonant continuum processes are studied with the invariant mass of the centrally produced two-pion system in the resonance-free region, $m_{\pi^+\pi^-}$$\lt$ 0.7 GeV or $m_{\pi^+\pi^-}$$\gt$ 1.8 GeV. Differential cross sections as functions of the azimuthal angle between the surviving protons, squared exchanged four-momenta, and $m_{\pi^+\pi^-}$ are measured in a wide region of scattered proton transverse momenta, between 0.2 and 0.8 GeV, and for pion rapidities $\lvert y\rvert$$\lt$ 2. A rich structure of interactions related to double-pomeron exchange is observed. A parabolic minimum in the distribution of the two-proton azimuthal angle is observed for the first time. It can be interpreted as an effect of additional pomeron exchanges between the protons from the interference between the bare and the rescattered amplitudes. After model tuning, various physical quantities are determined that are related to the pomeron cross section, proton-pomeron and meson-pomeron form factors, pomeron trajectory and intercept, and coefficients of diffractive eigenstates of the proton