49 research outputs found

    N-(Phosphonomethyl)Glycine Interactions With Soils

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    Glyphosate is a non selective, broad spectrum, postemergent herbicide widely used in weed control. The adsorption isotherms and surface coverage of glyphosate (NPhosphonomethylglycine,PMG) in aqueous suspensions of Argentine soils as a function ofPMG concentration and pH were measured. Zeta potential curves for the PMG/soils system were also determined. The formation of inner sphere surface complexes of PMG on the soil surface, were analyzed as a function of pH and surface coverage.Glifosato es un herbicida no selectivo, post-emergente y de amplio espectro, muy utilizado para el control de malezas. Las isotermas de adsorción y el cubrimiento superficial de glifosato (N-fosfonometilglicina, PMG) en suspensiones acuosas de suelos argentinos fueron medidas como una función de la concentración de PMG y del pH. También fueron determinadas las curvas de potencial zeta para el sistema PMG/suelo. La formación de complejos superficiales de esfera interna de PMG sobre la superficie de los suelos fue analizada como una función del pH y del cubrimiento superficial.Fil: Pessagno, Romina Carla. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Abad de Los Santos, Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Torres Sanchez, Rosa Maria. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Tecnología de Recursos Minerales y Cerámica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Tecnología de Recursos Minerales y Cerámica; Argentin

    Miradas audiovisuales sobre las prácticas de recuperación y conservación costera en La Paloma

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    El presente EFI se titula: «Miradas audiovisuales sobre las prácticas de recuperación y conservación costera en La Paloma», y surge como resultado de la búsqueda de articular la labor de diversas disciplinas y actores sociales en las localidades de La Paloma y La Pedrera, en el departamento de Rocha, Uruguay

    Comparative genomics of Cluster O mycobacteriophages

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    Mycobacteriophages - viruses of mycobacterial hosts - are genetically diverse but morphologically are all classified in the Caudovirales with double-stranded DNA and tails. We describe here a group of five closely related mycobacteriophages - Corndog, Catdawg, Dylan, Firecracker, and YungJamal - designated as Cluster O with long flexible tails but with unusual prolate capsids. Proteomic analysis of phage Corndog particles, Catdawg particles, and Corndog-infected cells confirms expression of half of the predicted gene products and indicates a non-canonical mechanism for translation of the Corndog tape measure protein. Bioinformatic analysis identifies 8-9 strongly predicted SigA promoters and all five Cluster O genomes contain more than 30 copies of a 17 bp repeat sequence with dyad symmetry located throughout the genomes. Comparison of the Cluster O phages provides insights into phage genome evolution including the processes of gene flux by horizontal genetic exchange

    Em torno da mesa do rei: artefatos, convivialidade e celebração no Rio de Janeiro joanino

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    Este artigo aborda um aspecto relevante do ritual das refeições na corte de D. João VI, no Rio de Janeiro: a prataria de mesa. Isto é, objetos de luxo destinados a servir e a consumir os alimentos. Com base em um inventário de bens de mesa enviados do Rio de Janeiro para Lisboa junto com o monarca em seu retorno a Portugal, em 1821, este artigo procura refletir sobre as funções e possíveis usos desses objetos, assim como sobre a importância desse universo material para o funcionamento, representação e celebração da Casa Real portuguesa na sua nova sede. O artigo argumenta que a presença e o uso de baixelas de prata de serviço, mas também de grande aparato, nas refeições públicas da família real pode contribuir para se repensar a imagem de uma corte pobre e sem brilho recorrentemente reforçada na historiografia do período joanino.This article discusses a specific issue of the royal dinner's rituals at the Court of Rio de Janeiro: the silver service: some luxury artifacts of different forms specially made to serve and consume food. Based on a inventory of these silver objects and also on a stock of table linen which were shipped to Lisbon, along with the royal family in 1821, The article intend to explore the functions and utilities of those objects at the table, as well as, analyze the importance of this material universe for the functioning, representation and celebration of the Portuguese Royal House in its new headquarters.The article argues that the use and even the exhibition of the banquet silver in public ceremonies may contribute to change a rather depreciative image of poverty the royal court in Brazil, which has being explored by the historiography for more than a hundred years

    Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

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    Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

    Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

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    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

    Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

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    There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity

    Analysis of Transitions in Sperm Motility

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    Introduction: In animals, the process of fertilization requires that a motile sperm interact with an egg. In most sperm, including those of insects, the motility apparatus is a eukaryotic flagellum and its regulation results from a series of tightly regulated molecular events. The flagellum is a biological nano-machine that is widely conserved through evolution. In recent studies using the mosquito Culex quinquefasciatus, Thaler et. al. (2013) observed a series of three flagellar waveforms that progressed from activation to full progressive motility. This same activation pattern occurred in sperm from a related species, Culex pipiens. The three distinct waveforms observed in vitro were: a low amplitude, low velocity, and high frequency waveform (A), a high amplitude, high velocity, and low frequency waveform (C), and a low velocity intermediate waveform that had superimposed features from both waveforms A and C (B). Based on these findings, we are interested in identifying the molecular switch responsible for the waveform transitions during sperm motility in C. pipiens. Here, we report our studies on C. pipiens with the aim of modeling the mosquito sperm flagellum as a nano-machine.Materials and Methods: Mosquitoes were euthanized by placing them in a chamber containing a piece of cotton soaked in chloroform. Seminal vesicles and accessory glands were removed while in PBS solution. They were then placed on a glass slide with a drop of insect Ringer’s solution and a coverslip. In some cases, only the seminal vesicles were used. Pressure was applied to the coverslip to break open accessory glands thereby activating sperm. Data was acquired with a Nikon Labphot Microscope at 10x magnification using phase contrast optics and a DAGE-MTI CCD 100 camera. Images were captured using Scion Image and processed using ImageJ to quantify wave parameters.Results and Discussion: Using phase contrast microscopy and image processing methodologies we obtained parameters for flagellar wavelength and amplitude as well as progressive velocity for sperm displaying waveforms A and C. In addition, we were able to determine the beat frequency for waveform C as well as the dimensions of the sperm head and tail. Once all the desired parameters have been measured with a large sample size, average parameters for each waveform, A and C, will be used to test current physical models. This will provide insight into the development of a mathematical model for this system that will describe the regulation of flagellar motion in both two- and three-dimensions.Conclusion: The results for the parameters describing waveforms A and C provide confidence in obtaining values that are accurate in order to develop a mathematical model for sperm motility. The model can then be combined with molecular events that occur during motility in order to provide a deeper understanding of flagellar motion. The eukaryotic flagellum serves as an example of a naturally occurring cellular motor and with a better understanding of the mechanism, can aid in the design of nano-scale biomimetic devices

    Localisation de véhicules intelligents par fusion de données multi-capteurs en milieu urbain

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    Afin d’améliorer la précision des systèmes de navigation ainsi que de garantir la sécurité et la continuité du service, il est essentiel de connaitre la position et l’orientation du véhicule en tout temps. La localisation absolue utilisant des systèmes satellitaires tels que le GPS est souvent utilisée `a cette fin. Cependant, en environnement urbain, la localisation `a l’aide d’un récepteur GPS peut s’avérer peu précise voire même indisponible `a cause des phénomènes de réflexion des signaux, de multi-trajet ou de la faible visibilité satellitaire. Afin d’assurer une estimation précise et robuste du positionnement, d’autres capteurs et méthodes doivent compléter la mesure. Dans cette thèse, des méthodes de localisation de véhicules sont proposées afin d’améliorer l’estimation de la pose en prenant en compte la redondance et la complémentarité des informations du système multi-capteurs utilisé. Tout d’abord, les mesures GPS sont fusionnées avec des estimations de la localisation relative du véhicule obtenues `a l’aide d’un capteur proprioceptif (gyromètre), d’un système stéréoscopique(Odométrie visuelle) et d’un télémètre laser (recalage de scans télémétriques). Une étape de sélection des capteurs est intégrée pour valider la cohérence des observations provenant des différents capteurs. Seules les informations validées sont combinées dans un formalisme de couplage lâche avec un filtre informationnel. Si l’information GPS est indisponible pendant une longue période, la trajectoire estimée par uniquement les approches relatives tend `a diverger, en raison de l’accumulation de l’erreur. Pour ces raisons, les informations d’une carte numérique (route + bâtiment) ont été intégrées et couplées aux mesures télémétriques de deux télémètres laser montés sur le toit du véhicule (l’un horizontalement, l’autre verticalement). Les façades des immeubles détectées par les télémètres laser sont associées avec les informations_ bâtiment _ de la carte afin de corriger la position du véhicule.Les approches proposées sont testées et évaluées sur des données réelles. Les résultats expérimentaux obtenus montrent que la fusion du système stéréoscopique et du télémètre laser avec le GPS permet d’assurer le service de localisation lors des courtes absences de mesures GPS et de corriger les erreurs GPS de type saut. Par ailleurs, la prise en compte des informations de la carte numérique routière permet d’obtenir une approximation de la position du véhicule en projetant la position du véhicule sur le tronc¸on de route correspondant et enfin l’intégration de la carte numérique des bâtiments couplée aux données télémétriques permet d’affiner cette estimation, en particulier la position latérale.In some dense urban environments (e.g., a street with tall buildings around), vehicle localization result provided by Global Positioning System (GPS) receiver might not be accurate or even unavailable due to signal reflection (multi-path) or poor satellite visibility. In order to improve the accuracy and robustness of assisted navigation systems so as to guarantee driving security and service continuity on road, a vehicle localization approach is presented in this thesis by taking use of the redundancy and complementarities of multiple sensors. At first, GPS localization method is complemented by onboard dead-reckoning (DR) method (inertial measurement unit, odometer, gyroscope), stereovision based visual odometry method, horizontal laser range finder (LRF) based scan alignment method, and a 2D GIS road network map based map-matching method to provide a coarse vehicle pose estimation. A sensor selection step is applied to validate the coherence of the observations from multiple sensors, only information provided by the validated sensors are combined under a loosely coupled probabilistic framework with an information filter. Then, if GPS receivers encounter long term outages, the accumulated localization error of DR-only method is proposed to be bounded by adding a GIS building map layer. Two onboard LRF systems (a horizontal LRF and a vertical LRF) are mounted on the roof of the vehicle and used to detect building facades in urban environment. The detected building facades are projected onto the 2D ground plane and associated with the GIS building map layer to correct the vehicle pose error, especially for the lateral error. The extracted facade landmarks from the vertical LRF scan are stored in a new GIS map layer. The proposed approach is tested and evaluated with real data sequences. Experimental results with real data show that fusion of the stereoscopic system and LRF can continue to localize the vehicle during GPS outages in short period and to correct the GPS positioning error such as GPS jumps; the road map can help to obtain an approximate estimation of the vehicle position by projecting the vehicle position on the corresponding road segment; and the integration of the building information can help to refine the initial pose estimation when GPS signals are lost for long time
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