Requirement of a Plasmid-Encoded Catalase for Survival of \u3cem\u3eRhizobium etli\u3c/em\u3e CFN42 in a Polyphenol-Rich Environment

Nitrogen-fixing bacteria collectively called rhizobia are adapted to live in polyphenol-rich environments. The mechanisms that allow these bacteria to overcome toxic concentrations of plant polyphenols have not been clearly elucidated. We used a crude extract of polyphenols released from the seed coat of the black bean to simulate a polyphenol-rich environment and analyze the response of the bean-nodulating strain Rhizobium etli CFN42. Our results showed that the viability of the wild type as well as that of derivative strains cured of plasmids p42a, p42b, p42c, and p42d or lacking 200 kb of plasmid p42e was not affected in this environment. In contrast, survival of the mutant lacking plasmid p42f was severely diminished. Complementation analysis revealed that the katG gene located on this plasmid, encoding the only catalase present in this bacterium, restored full resistance to testa polyphenols. Our results indicate that oxidation of polyphenols due to interaction with bacterial cells results in the production of a high quantity of H2O2, whose removal by the katG-encoded catalase plays a key role for cell survival in a polyphenol-rich environment

Competencia desleal de las importaciones de mochilas desde la percepción de los microempresarios de la galería Bellas Artes Cercado de Lima, 2022

La investigación tuvo como objetivo general describir la competencia desleal de las importaciones de mochilas desde la percepción de los microempresarios de la galería Bellas Artes Cercado de Lima, 2022. La metodología empleada fue de enfoque cualitativo, tipo investigación aplicada, diseño fenomenológico descriptivo y narrativo de tópico. Los participantes fueron cinco microempresarios, un gerente de una mype, un administrador general, cuatro propietarias de tienda y un ex trabajador de Indecopi del área comercial. La técnica utilizada, fue la entrevista semiestructurada y como instrumento fue la guía de la entrevista. Además, se realizó una revisión de literatura de revistas indexadas de bases de datos especializadas. Los resultados indicaron que la competencia desleal realizadas por las empresas importadoras, son constantes, y no hay un control adecuado por parte de las entidades gubernamentales (Indecopi). Se concluye, que a partir del año 2014 se incrementaron las importaciones de mochilas, y esto afectó a la producción nacional de mochilas y generó competencia desleales en la comercialización de mochilas afectando a: (1) consumidores, cuando compran mochilas de marcas replicas como productos originales, (2) competidores, cuando los precios de las mochilas importadas están por debajo del costo de producción de las mochilas nacionales (3) mercados nacional, cuando las empresas que lo conforman generan trabajos deshonestos con beneficio propio.. Se recomienda investigar a profundidad; porque, las empresas importadoras generan más competencias desleales

Producción de mielatos en colonias de abejas afectadas por el mal del río en Uruguay

In Uruguay, the excretions of the flatidae Epormenis cestri when located in sarandí colorado trees (Sebastiania schottiana) are the cause of the massive death of young honeybee larvae, a phenomenon that beekeepers call River disease. A strong income of honeydew is frequently observed in these affected colonies despite the con-tinuous loss of bees due to lack of replacement. The aim of this study was to determine a handling of the colonies that allows obtaining honeydew honey. Forty-eight colonies were transported to an apiary affected by River disease and were divided into 5 groups according to the following treatments: Group 1: regular honeydew har-vest, adding of brood and sugar syrup supply (N=10); Group 2: regular honeydew harvest and sugar syrup supply (N=10); Group 3: regular honeydew harvest and adding of brood (N=10); Group 4: regular honeydew harvest (N=10); Group 5: only one harvest of honeydew once the study had finished (N=8). The colonies from groups 1 and 3 produced the biggest amount of honeydew honey, averaging 32.0 and 28.6kg, respectively. The physicochemical analysis of honeydew honey showed characteristics of this product such as high electrical conductivity (0.98-1.14 mS/cm), diastase activity (>50%) and color (71-83 mm Pfund). This study provides the basis of a colony handling that allows beekeepers to obtain important harvests of a honeydew honey not yet known in the international market.En Uruguay, las excreciones de los flátidos Epormenis cestri, cuando se localizan en árboles de sarandí colo-rado (Sebastiania schottiana), causan mortalidad masiva de larvas jóvenes de abejas melíferas, fenómeno que los apicultores denominan «mal del río». Frecuentemente se observa una fuerte entrada de mielatos en las colonias afectadas a pesar del despoblamiento de abejas generado por la falta de reemplazo. El objetivo de este estudio fue determinar un manejo de las colonias que permita obtener mielatos. Se transportaron 48 colo-nias a un colmenar afectado por el mal del río y se dividieron en 5 grupos de acuerdo con el tratamiento: Grupo 1: cosecha regular de mielatos, adición de cría y suministro de jarabe de azúcar (N = 10); Grupo 2: cosecha regular de mielatos y suministro de jarabe de azúcar (N = 10); Grupo 3: cosecha regular de mielatos y adición de cría (N = 10); Grupo 4: cosecha regular de mielatos (N = 10); Grupo 5: solo una cosecha de mielatos una vez finalizadas las secreciones de E. cestri (N = 8). Las colonias de los grupos 1 y 3 produjeron la mayor cantidad de mielatos, con un promedio de 32,0 y 28,6 kg, respectivamente. El análisis fisicoquímico de los mielatos mostró características de este producto, como alta conductividad eléctrica (0.98-1.14 mS / cm), activi-dad diastasa (> 50%) y color (71-83 mm Pfund). Este estudio proporciona la base de un manejo de las colonias que permite a los apicultores obtener cosechas importantes de un mielato aún no conocido en el mercado internacional

Explorando a Aprendizagem Lúdica: Desenvolvimento de Jogo Interativo Utilizando Calculadora de Blocos

Games have great educational potential and attract people due to the interactivity they provide.Using playful elements in education can be promising, especially considering that the new generation grows up immersed in the digital world, acquiring skills naturally when interacting with technological devices.Technology can be an important ally to bring teaching closer to playfulness, allowing the time spent on electronic devices to generate positive results in education.In this sense, an educational game was developed for the Android platform, using the LUA programming language, the Corona SDK emulator and the Sublime Text text editor.The objective of the application is to help teach Mathematics through the block calculator, stimulating cognitive and social aspects, making studying a pleasant moment through challenges that encourage discovery and creating a pleasant study environment conducive to learning.   Keywords: Educational game. Games applied in teaching mathematics. Android. Lua. Corona SDK.Os jogos possuem um grande potencial educativo e atraem as pessoas devido à interatividade que proporcionam. Utilizar elementos lúdicos na educação pode ser promissor, especialmente considerando que a nova geração cresce imersa no mundo digital, adquirindo habilidades naturalmente ao interagir com dispositivos tecnológicos. A tecnologia pode ser uma aliada importante para aproximar o ensino do lúdico, permitindo que o tempo gasto em dispositivos eletrônicos gere resultados positivos na educação. Nesse sentido, foi desenvolvido um jogo educacional para a plataforma Android, utilizando a linguagem de programação LUA, o emulador Corona SDK e o editor de texto Sublime Text. O objetivo do aplicativo é auxiliar o ensino de Matemática através da calculadora de bloco, estimulando aspectos cognitivos e sociais, tornando o estudo um momento prazeroso por meio de desafios que incentivam a descoberta e criando um ambiente de estudo agradável e propício ao aprendizado.   Palavras-chave: Jogo educacional. jogos aplicados no ensino da Matemática. Android.  Lua. Corona SDK.o

Observations on the biology of Epormenis cestri, Berg, 1879 (Hemiptera, Flatidae)

En Uruguay Epormenis cestri, excreta un líquido dulce que es colectado por Apis mellifera provocando la enfermedad del Mal del Río, con impacto económico en la apicultura. Se describen los estadios de ciclo de vida, vegetación asociada y posibles organismos controladores biológicos de las poblaciones de este Flátido.In Uruguay, Epormenis cestri excretes a sweet liquid that is collected by Apis mellifera causing the Mal del Río disease, with an economic impact on beekeeping. The life cycle stages, associated vegetation and possible biological control organisms of the populations of Epormenis cestri are described

Analysis of harmonic distortion generated by PWM motor drives

This paper evaluates the harmonic distortion generated by PWM motor drives in an electrical industrial system of a wheat flour mill company. For this, a comparative study between two industrial circuits connected at the same point of common coupling with similar characteristics of load and transformers is presented. The difference is that one circuit has PWM motor drives and the other does not have them. In the study, a practical method based on the statistical characterization of the total harmonic distortion of voltage (THDV) and current (THDI), individual voltage distortion (IVD), individual current distortion (ICD) and K-Factor is applied. As result, it was observed that PWM motor drives generated harmonics voltage mainly of fifth and seventh order with values that exceed limits established by standards in both circuits. In the work is also demonstrated that in the analysis of harmonics is necessary to consider various parameters and not only one

Estimating induction motor efficiency under no-controlled conditions in the presences of unbalanced and harmonics voltages

This paper presents the application of a method to determine the output power, losses, and efficiency of induction motors, working in no-controlled conditions, in the presences of unbalanced and harmonics voltages. The method uses the steady state equivalent circuits, with some considerations for the analysis of motor performance, fed with unbalanced and harmonic voltages. The parameters of circuits are determined with low invasiveness, by applying a Bacterial Foraging Algorithm as technique of evolutionary search. With this, the efficiency and other operational parameters can be estimated at any operating point. The method was tested in a 12.6 kW motor working in an industrial network, with harmonics and voltage unbalanced

Características del fruto de tomate (Solanum lycopersicum) utilizando abejorros nativos (Bombus atratus) como polinizadores en invernáculo

In Uruguay, the production of tomato (Solanum lycopersicum) in greenhouse presents pollination issues that limit its yield. The use of bumblebees (Bombus spp.) as pollinators can help overcome this problem as they perform “buzzing pollination”, a behavior that makes them excellent pollinators of Solanaceae and particularly tomato. The aim of this study was to evaluate the effect of the native bumblebees Bombus atratus on the pro-portion of fruit set, weight, diameter, number of seeds and number of locules of tomato (LAPATAIA and ELPIDA varieties). An experience was carried out in Canelones, where the fruits from flowers pollinated by bumblebees and from flowers not visited by insects were compared; two other experiences carried out in Salto were similar to that of Canelones, but included flowers treated with hormones. In the three analyzed greenhouses the visit of bumblebees to the flowers increased the proportion of fruit set by 13 - 47%, compared to the result obtained in flowers not visited by the insects. Also, the pollinating action of bumblebees significantly improved the weight, size, and number of seeds compared to fruits obtained from flowers without access to pollinators. This improve-ment was recorded in the experience in Canelones and only in one of the Salto's experiences. On the other hand, a positive correlation was found between the number of seeds and the weight (R2 = 0.37, R2 = 0.53; LAPATAIA, ELPIDA, respectively) in the two tomato varieties. This study is the first in Uruguay to show the benefits of using native bumblebees in tomato production in greenhouses.En Uruguay, la producción de tomate (Solanum lycopersicum) bajo invernáculo presenta problemas de polini-zación que limitan su rendimiento. El uso de abejorros (Bombus spp.) como polinizadores puede contribuir a superar este problema, ya que realizan «polinización por zumbido», comportamiento necesario para polinizar las solanáceas y particularmente el tomate. El objetivo de este estudio fue evaluar el efecto de los abejorros nativos Bombus atratus en el porcentaje de cuajado, peso, diámetro, número de semillas y número de lóculos de tomate (variedades LAPATAIA y ELPIDA). Se realizó una experiencia en el departamento de Canelones donde se cotejaron los frutos de flores polinizadas por abejorros y flores no visitadas por los insectos; y dos experiencias en Salto iguales a la de Canelones, pero que incluían flores tratadas con hormonas. En los tres invernáculos la visita de los abejorros a las flores incrementó el porcentaje de cuajado entre 13 y 47 % en relación con el obtenido en flores no visitadas por los insectos. La acción polinizadora de los abejorros también mejoró signifi-cativamente el peso, tamaño y número de semillas respecto a frutos obtenidos de flores sin acceso a poliniza-dores en dos de las tres experiencias realizadas. Por otro lado, en las dos variedades de tomate se encontró una correlación positiva entre el número de semillas y el peso (R2=0,37, R2=0,53; LAPATAIA, ELPIDA, respectiva-mente). Este estudio es el primero en Uruguay que muestra los beneficios de utilizar abejorros nativos para mejorar la producción de tomates en invernáculos

Oil Seep Detection Using Microwave Remote Sensing at Espírito Santo Basin, Eastern Brazil

Hydrocarbon seepage phenomena can be found in most petroleum provinces located in both coastal and ocean regions. The present work aims to identify, map and quantify oil seep candidates in the maritime portion of the Espírito Santo Sedimentary Basin using Synthetic Aperture Radar imagery from Radarsat-2 and Sentinel-1. The selection of the SAR images was made based on their basin coverage area. Meteorological and oceanographic data, when available, were used to assist interpretation. Later, the presence of structures that may enable fluids to escape (faults, fractures, salt domes, etc.) was verified in 101 seismic lines. After detailed analysis, the obtained data were gathered, aiming to classify the oil seep candidates found according to their probability of happening. There were 3 parameters, subdivided into criteria, used in the ranking score: SAR (distance of vessels, number nearby possible seeps and feature size), Geological (morphotectonic domains) and Seismic (distance from seismic lines, presence of structures and distance from structure). Each criterion received grades ranging from 0.1 to 1.0. The final score is given by the arithmetic mean of the parameters. This allowed the seep candidates to be organized in a ranking. The methodology was successful in identifying 54 promising features in the Espírito Santo basin and northern Campos basin. Half of the seep candidates found, 27 features, obtained a grade higher than 0.7, which strengthens the idea of being oil seeps. As an outcome a map was made in 1:3,500,000 scale with the location of all oil seep candidates mapped in this petroleum province