19 research outputs found

    Biofiltración de ácido sulfhídrico (H2S), utilizando bagazo de caña de azúcar y piedra pómez como material de soporte

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    Experimentalmente se determinaron los valores de los parámetros de diseño y operación de un biofiltro para el control de las emisiones de ácido sulfhídrico (H2S) en un efluente gaseoso, utilizando como materiales de soporte bagazo de caña y piedra pómez inoculados con un consorcio microbiano capaz de degradar H2S. Se realizaron diferentes pruebas para determinar la capacidad máxima de eliminación de los soportes, así como el efecto de la concentración sobre la eficiencia de remoción. Por su efecto sobre el funcionamiento de los biofiltros también se estudió la variación de algunas propiedades de los soportes como el contenido de humedad, el pH y el contenido de sulfatos. La población de los diferentes grupos tróficos presentes en los soportes mostró una tendencia al crecimiento para las bacterias sulfooxidantes (BSO) y a la disminución para los heterótrofos, mohos y levaduras. Gracias a la inoculación y a la idoneidad de los soportes para el establecimiento y desarrollo del consorcio microbiano, los biofiltros presentaron un alto rendimiento desde el arranque. Continuamente se obtuvieron eficiencias de remoción mayores al 99%, siempre que las condiciones de operación fueron las adecuadas

    State of the climate in 2018

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    In 2018, the dominant greenhouse gases released into Earth’s atmosphere—carbon dioxide, methane, and nitrous oxide—continued their increase. The annual global average carbon dioxide concentration at Earth’s surface was 407.4 ± 0.1 ppm, the highest in the modern instrumental record and in ice core records dating back 800 000 years. Combined, greenhouse gases and several halogenated gases contribute just over 3 W m−2 to radiative forcing and represent a nearly 43% increase since 1990. Carbon dioxide is responsible for about 65% of this radiative forcing. With a weak La Niña in early 2018 transitioning to a weak El Niño by the year’s end, the global surface (land and ocean) temperature was the fourth highest on record, with only 2015 through 2017 being warmer. Several European countries reported record high annual temperatures. There were also more high, and fewer low, temperature extremes than in nearly all of the 68-year extremes record. Madagascar recorded a record daily temperature of 40.5°C in Morondava in March, while South Korea set its record high of 41.0°C in August in Hongcheon. Nawabshah, Pakistan, recorded its highest temperature of 50.2°C, which may be a new daily world record for April. Globally, the annual lower troposphere temperature was third to seventh highest, depending on the dataset analyzed. The lower stratospheric temperature was approximately fifth lowest. The 2018 Arctic land surface temperature was 1.2°C above the 1981–2010 average, tying for third highest in the 118-year record, following 2016 and 2017. June’s Arctic snow cover extent was almost half of what it was 35 years ago. Across Greenland, however, regional summer temperatures were generally below or near average. Additionally, a satellite survey of 47 glaciers in Greenland indicated a net increase in area for the first time since records began in 1999. Increasing permafrost temperatures were reported at most observation sites in the Arctic, with the overall increase of 0.1°–0.2°C between 2017 and 2018 being comparable to the highest rate of warming ever observed in the region. On 17 March, Arctic sea ice extent marked the second smallest annual maximum in the 38-year record, larger than only 2017. The minimum extent in 2018 was reached on 19 September and again on 23 September, tying 2008 and 2010 for the sixth lowest extent on record. The 23 September date tied 1997 as the latest sea ice minimum date on record. First-year ice now dominates the ice cover, comprising 77% of the March 2018 ice pack compared to 55% during the 1980s. Because thinner, younger ice is more vulnerable to melting out in summer, this shift in sea ice age has contributed to the decreasing trend in minimum ice extent. Regionally, Bering Sea ice extent was at record lows for almost the entire 2017/18 ice season. For the Antarctic continent as a whole, 2018 was warmer than average. On the highest points of the Antarctic Plateau, the automatic weather station Relay (74°S) broke or tied six monthly temperature records throughout the year, with August breaking its record by nearly 8°C. However, cool conditions in the western Bellingshausen Sea and Amundsen Sea sector contributed to a low melt season overall for 2017/18. High SSTs contributed to low summer sea ice extent in the Ross and Weddell Seas in 2018, underpinning the second lowest Antarctic summer minimum sea ice extent on record. Despite conducive conditions for its formation, the ozone hole at its maximum extent in September was near the 2000–18 mean, likely due to an ongoing slow decline in stratospheric chlorine monoxide concentration. Across the oceans, globally averaged SST decreased slightly since the record El Niño year of 2016 but was still far above the climatological mean. On average, SST is increasing at a rate of 0.10° ± 0.01°C decade−1 since 1950. The warming appeared largest in the tropical Indian Ocean and smallest in the North Pacific. The deeper ocean continues to warm year after year. For the seventh consecutive year, global annual mean sea level became the highest in the 26-year record, rising to 81 mm above the 1993 average. As anticipated in a warming climate, the hydrological cycle over the ocean is accelerating: dry regions are becoming drier and wet regions rainier. Closer to the equator, 95 named tropical storms were observed during 2018, well above the 1981–2010 average of 82. Eleven tropical cyclones reached Saffir–Simpson scale Category 5 intensity. North Atlantic Major Hurricane Michael’s landfall intensity of 140 kt was the fourth strongest for any continental U.S. hurricane landfall in the 168-year record. Michael caused more than 30 fatalities and 25billion(U.S.dollars)indamages.InthewesternNorthPacific,SuperTyphoonMangkhutledto160fatalitiesand25 billion (U.S. dollars) in damages. In the western North Pacific, Super Typhoon Mangkhut led to 160 fatalities and 6 billion (U.S. dollars) in damages across the Philippines, Hong Kong, Macau, mainland China, Guam, and the Northern Mariana Islands. Tropical Storm Son-Tinh was responsible for 170 fatalities in Vietnam and Laos. Nearly all the islands of Micronesia experienced at least moderate impacts from various tropical cyclones. Across land, many areas around the globe received copious precipitation, notable at different time scales. Rodrigues and Réunion Island near southern Africa each reported their third wettest year on record. In Hawaii, 1262 mm precipitation at Waipā Gardens (Kauai) on 14–15 April set a new U.S. record for 24-h precipitation. In Brazil, the city of Belo Horizonte received nearly 75 mm of rain in just 20 minutes, nearly half its monthly average. Globally, fire activity during 2018 was the lowest since the start of the record in 1997, with a combined burned area of about 500 million hectares. This reinforced the long-term downward trend in fire emissions driven by changes in land use in frequently burning savannas. However, wildfires burned 3.5 million hectares across the United States, well above the 2000–10 average of 2.7 million hectares. Combined, U.S. wildfire damages for the 2017 and 2018 wildfire seasons exceeded $40 billion (U.S. dollars)

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Psicología en contexto: retos y desafíos para los investigadores

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    La investigación ha ocupado un lugar central en la Facultad de Psicología de la Universidad de San Buenaventura Cali. Desde su creación hasta la fecha, la Facultad ha asumido una perspectiva crítica de la disciplina, con la intención explícita de promover un ejercicio profesional reflexivo y ajustado a las necesidades y características de nuestro contexto colombiano. Se trata, por supuesto, de una tarea interminable que solo puede llevarse a cabo por los senderos del diálogo y la discusión. El Primer Encuentro Regional de Psicología se gestó con ese fin y este volumen condensa las ponencias presentadas en dicho encuentro, el 20 de septiembre del 2012. Los trabajos incluyen avances y resultados de investigación, así como ponencias de reflexión teórica. El evento contó con la participación de estudiantes y docentes, así como de algunas ONG de la región. También nos acompañaron como invitados internacionales, la profesora Amelia Haydée Imbriano (Argentina) y el profesor Jorge Juan Román (Cuba).Universidad de San buenaventura - Cal

    Silicon in vascular plants: uptake, transport and its influence on mineral stress under acidic conditions

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    So far, considerable advances have been achieved in understanding the mechanisms of Si uptake and transport in vascular plants. This review presents a comprehensive update about this issue, but also provides the new insights into the role of Si against mineral stresses that occur in acid soils. Such information could be helpful to understand both the differential Si uptake ability as well as the benefits of this mineral element on plants grown under acidic conditions. Silicon (Si) has been widely recognized as a beneficial element for many plant species, especially under stress conditions. In the last few years, great efforts have been made to elucidate the mechanisms involved in uptake and transport of Si by vascular plants and recently, different Si transporters have been identified. Several researches indicate that Si can alleviate various mineral stresses in plants growing under acidic conditions, including aluminium (Al) and manganese (Mn) toxicities as well as phosphorus (P) deficiency all of which are highly detrimental to crop production. This review presents recent findings concerning the influence of uptake and transport of Si on mineral stress under acidic conditions because a knowledge of this interaction provides the basis for understanding the role of Si in mitigating mineral stress in acid soils. Currently, only four Si transporters have been identified and there is little information concerning the response of Si transporters under stress conditions. More investigations are therefore needed to establish whether there is a relationship between Si transporters and the benefits of Si to plants subjected to mineral stress. Evidence presented suggests that Si supply and its subsequent accumulation in plant tissues could be exploited as a strategy to improve crop productivity on acid soils

    Biodiversidad 2015. Reporte de Estado y Tendencias de la Biodiversidad Continental de Colombia

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    El propósito de este documento es fortalecer la capacidad de agentes públicos y privados para la aplicación de la PNGIBSE, que constituye en sí misma una apuesta de interfaz entre ciencia, política y sociedad en la perspectiva de construir sostenibilidad en el desarrollo. Además de ello, representa un insumo para el seguimiento a los compromisos del país frente a convenios e iniciativas internacionales (CDB, IPBES, OCDE), así como un mecanismo pedagógico para generar interés, conciencia y apropiación de las diferentes dimensiones de la biodiversidad del país. En esta oportunidad, el reporte avanza en el desarrollo de nuevas infografías vinculadas con diferentes fuentes de información que garantizan la calidad de los datos con los que se propone y representa el estado de la biodiversidad y de su gestión en Colombia. Incluye como novedad la presentación de material en portal web dedicado (reporte.humboldt.org.co), de manera que todas las personas puedan apropiarse e interactuar con el contenido de manera más efectiva. La perspectiva es construir un modelo en tiempo real del trabajo que se desarrolla en el país para conocer, proteger, utilizar o restaurar su biodiversidad y servicios ecosistémicos, promoviendo la apropiación de todos los ciudadanos e instituciones en la tarea. Biodiversidad 2015, es evidente, aún no está en capacidad de dar cuenta de todos los procesos de gestión de biodiversidad que se dan en Colombia, liderados por múltiples actores y a todas las escalas. Paulatinamente esperamos poder abrir el espacio para incrementar la visibilidad de todas y cada una de las iniciativas que se adelanten, a sabiendas de que la posibilidad de encontrar nuevas respuestas y mejores prácticas no depende del Instituto ni de ninguna instancia en particular, sino de la capacidad colectiva de aprendizaje. Así, esperamos que este nuevo paso en la construcción de un producto colaborativo sea del interés de todos y nos permita avanzar en esa dirección. reporte.humboldt.org.coBogotá, D. C

    International Nosocomial Infection Control Consortium report, data summary of 50 countries for 2010-2015: Device-associated module

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    •We report INICC device-associated module data of 50 countries from 2010-2015.•We collected prospective data from 861,284 patients in 703 ICUs for 3,506,562 days.•DA-HAI rates and bacterial resistance were higher in the INICC ICUs than in CDC-NHSN's.•Device utilization ratio in the INICC ICUs was similar to CDC-NHSN's. Background: We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2010-December 2015 in 703 intensive care units (ICUs) in Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific. Methods: During the 6-year study period, using Centers for Disease Control and Prevention National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI), we collected prospective data from 861,284 patients hospitalized in INICC hospital ICUs for an aggregate of 3,506,562 days. Results: Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the INICC medical-surgical ICUs, the pooled rate of central line-associated bloodstream infection, 4.1 per 1,000 central line-days, was nearly 5-fold higher than the 0.8 per 1,000 central line-days reported from comparable US ICUs, the overall rate of ventilator-associated pneumonia was also higher, 13.1 versus 0.9 per 1,000 ventilator-days, as was the rate of catheter-associated urinary tract infection, 5.07 versus 1.7 per 1,000 catheter-days. From blood cultures samples, frequencies of resistance of Pseudomonas isolates to amikacin (29.87% vs 10%) and to imipenem (44.3% vs 26.1%), and of Klebsiella pneumoniae isolates to ceftazidime (73.2% vs 28.8%) and to imipenem (43.27% vs 12.8%) were also higher in the INICC ICUs compared with CDC-NHSN ICUs. Conclusions: Although DA-HAIs in INICC ICU patients continue to be higher than the rates reported in CDC-NSHN ICUs representing the developed world, we have observed a significant trend toward the reduction of DA-HAI rates in INICC ICUs as shown in each international report. It is INICC's main goal to continue facilitating education, training, and basic and cost-effective tools and resources, such as standardized forms and an online platform, to tackle this problem effectively and systematically
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