Efecto de fertilización nitrogenada en maíz (Zea mays L.) sobre poblaciones de hongos micorrízicos, en Babahoyo

The present work was carried out in the experimental farm "San Pablo" of the University of Babahoyo located at km 7,5 of the Babahoyo Montalvo road, in the province of Los Ríos. Somma maize hybrid was used as planting material. For the research, a field work with twelve treatments and three repetitions was designed. The first six treatments were applied with VAM mycorrhizae from the Huxtable company at doses of 1,0 l/ha with different levels of nitrogen fertilization of 180, 160, 140, 120, 100 and 0 kg/ha of nitrogen, the remaining six treatments they did not receive mycorrhizal applications, but had the same levels of fertilization. The statistical design applied was factorial, with the respective analysis of variance and the 95% tukey test of significance in the comparison of means. For the establishment of the crop, the pertinent cultural tasks were carried out, such as land preparation, sowing, weed control, irrigation, fertilization, phytosanitary controls and harvesting. With the results obtained, it was determined that the application of mycorrhizae at a dose of 1,0 l/ha maintains the populations of the fungus constantly in the soil, which is not possible without its application, this due to the application of nitrogen fertilizers reduces the populations. Nitrogen applications between 160-180 kg/ha significantly reduce mycorrhiza populations in soils, with or without fertilization. The use of mycorrhiza 1.0 l/ha + 180 kg/ha of nitrogen with a production of 7867,70 kg/ha presented the highest yield, however, its effects on populations of microorganisms are evident.El presente trabajo se efectuó en la granja experimental “San Pablo” de la Universidad de Babahoyo ubicada en el km 7,5 de la vía Babahoyo Montalvo, en la provincia de Los Ríos. Como material de siembra se utilizó el hibrido de maíz Somma. Para la investigación se diseñó un trabajo de campo con doce tratamientos y tres repeticiones. Los primeros seis tratamientos fueron aplicados con micorrizas VAM de la empresa Huxtable a dosis de 1,0 l/ha con diferentes niveles de fertilización nitrogenada de 180, 160, 140, 120, 100 y 0 kg/ha de nitrógeno, los seis tratamientos restantes no recibieron aplicaciones de micorrizas, pero tuvieron los mismos niveles de fertilización. El diseño estadístico aplicado fue factorial, con el respectivo análisis de la varianza y la prueba de significancia de Tukey al 95% en la comparación de medias. Para el establecimiento del cultivo se realizaron las labores culturales pertinentes, tales como preparación del terreno, siembra, control de malezas, riego, fertilización, controles fitosanitarios y cosecha. Con los resultados obtenidos se determinó que la aplicación de micorrizas en dosis 1,0 l/ha mantiene las poblaciones del hongo de manera constante en el suelo, lo cual no es posible sin su aplicación, esto debido a la aplicación de fertilizantes nitrogenados disminuye las poblaciones. Aplicaciones de nitrógeno entre 160-180 kg/ha reducen de manera considerable poblaciones de micorrizas en los suelos, con o sin fertilización.   &nbsp

Estudo situacional da produção e comercialização de grãos de cacau na área de urdaneta, los ríos / Situational study of the production and marketing of cocoa beans in the area of urdaneta, los ríos

El cultivo de cacao (Theobroma cacao L) en el Ecuador es conocido como la “pepa de oro”, siendo uno de los principales productos que oferta mayor divisas, ingreso, exportación y empleos a las familias campesinas. Este cultivo ha ocupado uno de los rubros más importante en la actividad comercial, social y ambiental del Ecuador, seguido de una producción mundial que se incrementa día con día, influenciada por el aumento de la demanda, ya que este producto es parte de la dieta alimenticia humana, al igual para los procesos de derivación como materia prima que tiene el producto. Este trabajo tuvo como objetivo determinar el estudio situacional de la producción y comercialización del grano de cacao en la zona de Ricaurte, Los Ríos, teniendo como objetivos específicos: identificar la situación socio - económica de la comercialización del grano de cacao en Ricaurte y analizar la estructura y funcionamiento de la cadena productiva del cacao en la zona de Ricaurte Para este análisis se empleó como metodología el uso de encuestas de tipo cerrada a los centros de acopio de la localidad, estas matrices fueron realizadas telemáticamente debido a la crisis sanitaria que atraviesa el país, cuyos datos fueron procesados e interpretados con cálculo de números (porcentajes) y gráficos de barras. Las conclusiones determinan que los agricultores no tienen capacitación técnica para el asesoramiento y comercialización del cultivo, ausencia de financiamiento por parte de las instituciones, obteniendo como resultado precios bajos y malas condiciones del producto al momento de la venta

Col·leccions singulars a les biblioteques de la Universitat Autònoma de Barcelona

Les biblioteques de la Universitat Autònoma de Barcelona són, com la mateixa institució, entitats amb una història curta; però, malgrat que van començar la seva activitat fa menys de cinquanta anys, els seus fons han assolit una importància considerable i superen en quantitat els de moltes universitats centenàries del nostre context. Les col·leccions de fons antics de les biblioteques de la UAB són, per aquesta mateixa raó, limitades, si bé se n'han anat creant algunes d'especialitzades d'importància i valor singulars. Aquest llibre pretén donar-les a conèixer al món universitari, però també al públic en general. Moltes són col·leccions úniques, fruit del treball persistent del personal bibliotecari, del professorat i de la generositat de moltes persones particulars, que han donat o llegat a la nostra universitat els seus arxius, les seves biblioteques personals o les seves col·leccions especialitzades. Aquestes col·leccions comprenen molts àmbits de les ciències i de les humanitats i, molt sovint, es tracta de col·leccions úniques al nostre país. Hi trobareu també un ampli ventall de tipologies documentals en llengües diverses, des dels mapes fins als audiovisuals, des de les revistes i diaris fins als cartells, des dels fons antics fins als més actuals, arxius personals i fons institucionals. Les biblioteques de la Universitat, a més d'inventariar i catalogar aquests fons documentals, també porten a terme una tasca constant de preservació i difusió, que sovint inclou la digitalització dels documents, que després es posen a l'abast del públic general mitjançant el dipòsit digital institucional (ddd.uab.cat)

Gaia Data Release 1: the archive visualisation service

Context. The first Gaia data release (DR1) delivered a catalogue of astrometry and photometry for over a billion astronomical sources. Within the panoplyof methods used for data exploration, visualisation is often the starting point and even the guiding reference for scientific thought. However, this is a volume of data that cannot be efficiently explored using traditional tools, techniques, and habits. Aims. We aim to provide a global visual exploration service for the Gaia archive, something that is not possible out of the box for most people. The service has two main goals. The first is to provide a software platform for interactive visual exploration of the archive contents, using common personal computers and mobile devices available to most users. The second aim is to produce intelligible and appealing visual representations of the enormous information content of the archive. Methods. The interactive exploration service follows a client-server design. The server runs close to the data, at the archive, and is responsible for hiding as far as possible the complexity and volume of the Gaia data from the client. This is achieved by serving visual detail on demand. Levels of detail are pre-computed using data aggregation and subsampling techniques. For DR1, the client is a web application that provides an interactive multi-panel visualisation workspace as well as a graphical user interface. Results. The Gaia archive Visualisation Service offers a web-based multi-panel interactive visualisation desktop in a browser tab. It currently provides highly configurable 1D histograms and 2D scatter plots of Gaia DR1 and the Tycho-Gaia Astrometric Solution (TGAS) with linked views. An innovative feature is the creation of ADQL queries from visually defined regions in plots. These visual queries are ready for use in the Gaia Archive Search/data retrieval service. In addition, regions around user-selected objects can be further examined with automatically generated SIMBAD searches. Integration of the Aladin Lite and JS9 applications add support to the visualisation of HiPS and FITS maps. The production of the all-sky source density map that became the iconic image of Gaia DR1 is described in detail. Conclusions. On the day of DR1, over seven thousand users accessed the Gaia Archive visualisation portal. The system, running on a single machine, proved robust and did not fail while enabling thousands of users to visualise and explore the over one billion sources in DR1. There are still several limitations, most noticeably that users may only choose from a list of pre-computed visualisations. Thus, other visualisation applications that can complement the archive service are examined. Finally, development plans for Data Release 2 are presented

Margarita de Sossa, Sixteenth-Century Puebla de los Ángeles, New Spain (Mexico)

Margarita de Sossa’s freedom journey was defiant and entrepreneurial. In her early twenties, still enslaved in Portugal, she took possession of her body; after refusing to endure her owner’s sexual demands, he sold her, and she was transported to Mexico. There, she purchased her freedom with money earned as a healer and then conducted an enviable business as an innkeeper. Sossa’s biography provides striking insights into how she conceptualized freedom in terms that included – but was not limited to – legal manumission. Her transatlantic biography offers a rare insight into the life of a free black woman (and former slave) in late sixteenth-century Puebla, who sought to establish various degrees of freedom for herself. Whether she was refusing to acquiesce to an abusive owner, embracing entrepreneurship, marrying, purchasing her own slave property, or later using the courts to petition for divorce. Sossa continued to advocate on her own behalf. Her biography shows that obtaining legal manumission was not always equivalent to independence and autonomy, particularly if married to an abusive husband, or if financial successes inspired the envy of neighbors

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV