Plant development effects of biochars from different raw materials

Biochar can provide multiple benefits in the ecosystem. However, the presence of phytotoxic compounds in some biochars is an important concern that needs to be addressed and that depends on the raw material and the pyrolysis conditions used in biochar production. For example, sewage sludge biochars can have elevated heavy metal con- tents as they were present in the feedstock and were enriched during pyrolysis. Also during carbonization, some phytotoxic compounds such as polycyclic aromatic hydrocarbons (PAHs), polyphenols or volatile organic com- pounds (VOCs) could be formed representing a risk of contamination to soils and crops. In this work we report the results from seed germination and plant development for three biochars prepared from wood, paper sludge plus wheat husks and sewage sludge. Five higher plant species (cress, lentils, cucumber, tomato and lettuce) were studied. Biochar from wood shows seed inhibition in several species and the paper sludge biochar on lettuce. For the rest, the effect on seed germination was positive. No inhibition of root growth was detected, but in some cases leaves and stems growth were inhibited. Our results are significant in terms of advancing or current understanding on the impacts of biochar on vegetative growth and linking those effects to biochar properties

Factors driving the carbon mineralization priming effect in a sandy loam soil amended with different types of biochar

The effect of biochar on the soil carbon mineral- ization priming effect depends on the characteristics of the raw materials, production method and pyrolysis conditions. The goal of the present study is to evaluate the impact of three different types of biochar on physicochemical properties and CO2 emissions of a sandy loam soil. For this purpose, soil was amended with three different biochars (BI, BII and BIII) at a rate of 8 wt % and soil CO2 emissions were measured for 45 days. BI is produced from a mixed wood sieving from wood chip production, BII from a mixture of paper sludge and wheat husks and BIII from sewage sludge. Cumulative CO2 emissions of biochars, soil and amended soil were well fit to a simple first-order kinetic model with correlation coef- ficients (r 2 ) greater than 0.97. Results show a negative prim- ing effect in the soil after addition of BI and a positive prim- ing effect in the case of soil amended with BII and BIII. These results can be related to different biochar properties such as carbon content, carbon aromaticity, volatile matter, fixed carbon, easily oxidized organic carbon or metal and phenolic substance content in addition to surface biochar properties. Three biochars increased the values of soil field capacity and wilting point, while effects over pH and cation exchange capacity were not observed

Viability of the biochar production from different manure wastes in the Amblés Valley (Ávila, Spain)

In the last years, intensive animal husbandry production has led to a large concentration of animals in small areas. This has resulted in the production of excessive amounts of manures with insufficient nearby land for application. One of this areas is the Amblés Valley located in the centre of Spain, near to Ávila city, with an extension of 167472 ha of which 88.9% is agricultural land. This valley has an important livestock focused on pig, cattle, chicken production which is associated with the generation of more than 200,000 t/year of manure. There are a number of environmental problems associated with these intensive agricultural systems, including N and P pollution of water bodies, methane emissions and odour pollution. These serious environmental threats are called for innovative environmental management approaches. A feasible technology for the management of manures, offering a potential to valorise these wastes, is pyrolysis, which results in the production of biochar. The objective of this work is evaluated the technical and economic feasibility of the production of biochar in Amblés Valley (Spain)

Effects of biochar prepared from organic waste on soil properties

Biochar is a carbon-rich solid obtained by the thermal decomposition of organic matter under a limited supply of oxygen and at relatively low temperatures. Biochar can be prepared from the pyrolysis of different organic feed- stocks, such as wood and biomass crops, agricultural by-products, different types of waste or paper industry waste materials . The pyrolysis procedure of waste, i.e. sewage sludge, has mainly two advantages, firstly, it removes pathogens from waste and, secondly, biochar can reduce the leaching of heavy metals present in raw sewage sludge. This trend of the use of waste material as feedstocks to the preparation of biochar is increasing in the last years due to industrial development and economic growth imply an increase in waste generation. The application of biochar may have positive effects on soil physical properties as water holding capacity and structure or on soil biological activity and soil quality. Also, biochar can be used to remove water pollutants and can be used in multiple ways in soil remediation due to its adsorption of pesticides or metals. Also, biochar contribute to carbon sequestration due to carbon stability of biochar materials. The objective of this presentation is to review the positive effects of the biochar prepared from organic waste on soil properties

Perspectivas de innovación en gestión, educación ambiental para la adaptación y la mitigación

Esta publicación del libro-foro sobre ciudad y cambio climático responde al aporte de los diferentes profesionales de las entidades públicas y privadas que participaron en calidad de conferencistas, ponentes, panelistas y expositores y compartieron sus experiencias en la ciudad como una contribución al conocimiento de las comunidades acerca de la creciente importancia y consideración de la adaptación y mitigación. Se consideraron acciones de políticas públicas por parte de las administraciones públicas, los sectores económicos y la sociedad, grupos ecológicos y fundaciones ecológicas y de igual forma las acciones y grandes esfuerzos realizados por el Ministerio del Ambiente, el IDEAM, la CAR, la Secretaría de Ambiente, el Jardín Botánico, la Red RAUS y de los grupos de investigación de las universidades

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Evaluacion del uso de residuos organicos para la produccion de biochar y su aplicacion como enmienda organica

En la actualidad el uso de biochar ha despertado gran interés por sus supuestos aportes en la lucha contra el calentamiento global, la mejora de la calidad de los suelos y el aumento de la productividad de cultivos. Esta tesis se ha centrado en el estudio de los efectos de este material carbonoso en los suelos y en evaluar la viabilidad de gestión de diversos residuos organicos mediante procesos de pirólisis o gasificación. Con este propósito, se estudió la influencia de distintas materias primas y procesos de producción sobre las propiedades de los biochars y los impactos asociados a su uso como enmienda organica. La tesis esta estructurada en cinco capítulos. El objetivo del capítulo tres fue estudiar la influencia de la materia prima (residuos ganaderos) y de la temperatura de pirólisis sobre las propiedades de los biochars, para ello se hizo una caracterización de todos los materiales. Los resultados indican que las propiedades agronómicas de los biochars son muy variables según la biomasa empleada y las condiciones de producción. Sin embargo, en todos los casos se observó una reducción de las fracciones móviles de metales traza en los biochars. En el cuarto capítulo se determinó la influencia del biochar sobre las propiedades biológicas del suelo, con este fin, se desarrollaron dos estudios en los que se evaluaron los efectos del biochar sobre la respiración del suelo y las actividades enzimaticas. Los resultados indican que tras el proceso de pirólisis la biomasa alcanza mayor estabilidad, por lo tanto, la mineralización del carbono es menor cuando se usa biochar como enmienda organica. Sin embargo, los biochars producidos a altas temperaturas tienen un impacto negativo sobre los microorganismos del suelo. El objetivo del capítulo cinco fue evaluar la influencia del biochar sobre la germinación y el desarrollo de las plantas. Para ello, se hizo un ensayo de germinación, un ensayo de producción vegetal y un analisis foliar. Los resultados indican que los efectos del biochar varían en función de sus propiedades y de la especie vegetal utilizada, lo cual sugiere que no todos los biochars tienen el potencial de incrementar la productividad de los cultivos. ABSTRACT Nowadays the use of biochar on agricultural activities has turned into an interesting option that could not only mitigate global warming but that could also improve soil qualities and crop productivity. Therefore, this thesis has been developed in order to evaluate effects of this carbonaceous material when it is used as soil organic amendment and also to evaluate the viability of pyrolysis and gasification process on the organic wastes management. Accordingly, the effect of different types of organic wastes and production parameters on biochar properties were evaluated. The impact of biochar as organic amendment was studied as well. This thesis has five chapters. In the first and second chapters an introduction and objectives were done. In the third chapter the influence of biomass (manure wastes) and pyrolysis temperature on biochar agronomic properties were studies. Accordingly, a characterization of all materials were done. The results indicate that it is possible to produce biochar with different properties according to the organic waste used such as feedstock and the pyrolysis conditions. Furthermore, a reduction of mobile forms of metals on biochars was observed. In the fourth chapter, the biochar influence on soil biological properties were determined. To this end, two independent studies were carried out in order to evaluate the effects of biochar on the soil respiration process and on the enzymatic activities. The results show that the biomass become more stable after the pyrolysis process, therefore, when biochar is used as an organic amendment, the carbon mineralization in soils decreases. However, a negative respond of soil microorganism was observed when biochar produced at high temperatures was used. The fifth chapter includes an evaluation of the biochar influence on germination and plant development. To this end, three assays -germination test, vegetal mass production and leaf assay- were done. According to the results, the biochar effects depend on its properties and this effects change significantly according to the plant that is used. This fact suggests that not all biochars have the potential to improve crops productivity

Evaluación a la gestión de recurso humano en el área de selección de personal del Instituto de Seguros Sociales en los últimos 12 años (1993 –2005).

Para lograr una mejor eficiencia en el proceso de organización de personal (Análisis Ocupacional, Reclutamiento, y Selección de Personal) se requiere una estructura de cargos interrelacionados para que las personas trabajen eficientemente en la búsqueda de los objetivos de la Institución. Es fundamental crear conciencia de que los recursos humanos son los activos más importantes que tiene la Institución y su efectiva gerencia es la clave de su éxito, dicho éxito es más probable de lograr si las políticas y los procedimientos de personal están estrechamente ligados y hacen una contribución importante al logro de los objetivos y planes estratégicos institucionales, a la vez, la cultura, los valores, el clima organizacional y la conducta gerencial ejercerán una influencia primordial en el logro de la excelencia lo cual significa que esos valores posiblemente deban cambiar o ser reforzados mediante un esfuerzo continuo, comenzando desde la cima para conseguir que esos valores sean aceptados y observados en la práctica. Para la Institución debe ser importante la implementación de los análisis de cargos en sus diferentes áreas ya que estas son herramientas muy significativas en los procesos de Organización de Personal o al momento de realizar evaluación de desempeño, diseño o rediseño de puestos, valoración de cargos, el cual le permita a la Institución mejorar su Gestión Administrativa. Esta estructura es una herramienta básica para mantener una equidad interna en la administración de la Institución; ya que dentro de una misma empresa existen grandes diferencias entre los oficios, estas diferencias obedecen a que cada uno requiere habilidad, responsabilidad y esfuerzos diferentes y a que el trabajo que se desarrolla en condiciones ambientales diversas. Por estos motivos se hará una evaluación rigurosa a los procesos de análisis ocupacional, reclutamiento y selección de personal con el propósito de analizar y organizar la información recolectada para mostrar así los resultados obtenidos en la investigación, y plantear posibles soluciones para el mejoramiento de la Gestión Administrativa del ISS

La influencia de la interacción cultural en la enseñanza del español como lengua extranjera (LE)

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Financial Stability Report - First Semester 2018

1.La recuperación económica ha mitigado gradualmente las principales vulnerabilidades de corto plazo para la estabilidad del sistema financiero. 2.Los establecimientos de crédito continúan manteniendo indicadores sólidos de solvencia y liquidez, pese a la reducción en la rentabilidad y al bajo crecimiento del volumen de crédito. 3.Las principales vulnerabilidades para la estabilidad financiera están asociadas con: •El efecto rezagado del bajo crecimiento económico sobre la materialización del riesgo de crédito. •El riesgo de un menor crecimiento económico en el futuro cercano. 4.Al cierre de 2017 se observan menores incrementos en la cartera riesgosa y vencida del sector corporativo y de los hogares colombianos.1. The recovery of the Colombian economy has gradually mitigated the main short-term vulnerabilities for the financial stability of the system. 2. Credit institutions maintain solid solvency and liquidity indicators, despite the reduction in profitability and the slow growth in the volume of credit. 3. The main vulnerabilities for the financial stability of the Colombian economy at the moment are associated with: - The lagged effect of low economic growth on the materialization of credit risk. - The risk of a return to a path of economic slowdown in the near future. 4. At the closing of 2017, non-performing loans to the corporate sector and Colombian households still showed positive (albeit declining) rates of growth