Comparison of measurements of peroxyacyl nitrates and primary carbonaceous aerosol concentrations in Mexico City determined in 1997 and 2003

International audiencePeroxyacetyl nitrate (PAN) concentrations in ambient air can be a good indicator of air quality and the effectiveness of control strategies for reducing ozone levels in urban areas. As PAN is formed by the oxidation of reactive hydrocarbons in the presence of nitrogen dioxide (NO2), it is a direct measure of the peroxyacyl radical levels produced from reactive organic emissions in the urban air shed. Carbon soot, known as black carbon or elemental carbon, is a primary atmospheric aerosol species and is a good indicator of the levels of combustion emissions, particularly from diesel engines, in major cities. Mexico City is the second largest megacity in the world and has long suffered from poor air quality. Reported here are atmospheric measurements of PAN and black carbon obtained in Mexico City during the Mexico Megacity 2003 field study. These results are compared with measurements obtained earlier during the Investigación sobre Materia Particulada y Deterioro Atmosférico ? Aerosol and Visibility Research (IMADA-AVER) campaign in 1997 to obtain an estimate of the changes in emissions in Mexico City and the effectiveness of control strategies adopted during that time. Concentrations of PAN in 1997 reached a maximum of 34 ppb with an average daily maximum of 15 ppb. The PAN levels recorded in 2003 were quite different, with an average daily maximum of 3 ppb. This dramatic reduction in PAN levels observed in 2003 indicate that reactive hydrocarbon emissions have been reduced in the city due to controls on olefins in liquefied petroleum gas (LPG) and also due to the significant number of newer vehicles with catalytic converters that have replaced older higher emission vehicles. In contrast, black/elemental carbon levels were similar in 1997 and 2003 indicating little improvement likely due to the lack of controls on diesel vehicles in the city. Thus, while air quality and ozone production has improved, Mexico City and other megacities continue to be a major source of black carbon aerosols, which can be an important species in determining regional radiative balance and climate

Clustering approach applied on an artificial neural network model to predict PM10 in mega cities of México

A cluster-based artificial neural network model called CLASO (Classification-Assemblage-Association) has been proposed to predict the maximum of the 24-h moving average of PM10 concentration on the next day in the three largest metropolitan areas of Mexico. The model is a self-organised, real-time learning neural network, which builds its topology via a process of pattern classification by using an historical database. This process is based on a supervised clustering technique, assigning a class to each centroid of the hidden layer, employing the Euclidean distance as a hierarchical criterion. A set of ARIMA models was compared with CLASO model in the forecast performance of the 24-h average PM10 concentration on the next day. In general, CLASO model produced more accurate predictions of the maximum of the 24-h moving average of PM10 concentration than the ARIMA models, although the latter showed a minor tendency to underpredict the results. The CLASO model solely requires to be built a historical database of the air quality parameter, an initial radius of classification and the learning factor. CLASO has demonstrated acceptable predictions of 24-h average PM10 concentration by using exclusively regressive PM10 concentrations. The forecasting capabilities of the model were found to be satisfactory compared to the classical models, demonstrating its potential application to the other major pollutants used in the Mexican air quality index

Edaphic Factors and Initial Conditions Influence Successional Trajectories of Early Regenerating Tropical Dry Forests

Edaphic factors and initial conditions can regulate the speed of forest succession. Edaphic factors, which include soil chemistry and topography, determine soil resource availability and can filter species as forests mature. Initial plant cover early in succession can determine the rates at which secondary forests change in structure, richness, biomass and composition over time. While some of the effects of edaphic factors and initial conditions on forest succession have been studied, how they simultaneously modify young regenerating tropical forest has rarely been examined. We surveyed 22 young forests plots in Panama for 7 years (11, 6 and 3‐year‐old stands when censuses began). We study how tree and liana species composition change early in succession, as well as how edaphic factors (soil nutrients and topography) and initial conditions (initial basal area and forest canopy cover) influence changes in tree and liana abundance, species richness, biomass and composition throughout succession. We found that edaphic factors and initial conditions explained up to 45% of the variation in the successional trajectories for trees and lianas. Soil nutrients had a significant positive effect on the changes in tree biomass accretion, while topography significantly contributed to community similarity of large lianas over time. Initial basal area had a significant negative effect on the changes in sapling abundance and tree richness over time and a positive marginal effect on tree biomass accretion. Forest canopy cover only had a positive marginal effect on changes in sapling abundance. Tree abundance, biomass and richness increased over time, while sapling abundance, biomass and richness remained stable or decreased, probably due to community thinning. However, changes over time of small and large lianas diverged, probably due to differential resource availability that affected lianas but not trees. Synthesis. Soil fertility, topography and initial basal area influence early forest regeneration. Higher soil fertility can allow trees to fix carbon faster, and lianas might show habitat association to ridges and slopes. Basal area can determine how fast saplings and trees change in abundance, richness and biomass over time by possibly affecting space availability for recruitment and light availability for growth

Air quality in North America's most populous city ? overview of the MCMA-2003 campaign

International audienceExploratory field measurements in the Mexico City Metropolitan Area (MCMA) in February 2002 set the stage for a major air quality field measurement campaign in the spring of 2003 (MCMA-2003). Involving over 100 scientists from more than 30 institutions in Mexico, the United States and Europe, MCMA-2003 revealed important new insights into the meteorology, primary pollutant emissions, ambient secondary pollutant precursor concentrations, photochemical oxidant production and secondary aerosol particle formation in North America's most populated and polluted megacity. A description of meteorological and atmospheric chemistry and aerosol microphysics measurements performed during MCMA-2003 is presented. More than 40 published or submitted MCMA-2003 research papers are reviewed and key discoveries pertinent to understanding and improving air quality in Mexico City and similar megacities in the developing world are summarized

Spatio temporal and climatic analysis of the high Andean wetland of Chalhuanca (Peru) during the period 1986-2016

[ES] Los humedales altoandinos son considerados ecosistemas frágiles que proporcionan servicios ecosistémicos para el mantenimiento de la biodiversidad y economía andina, sin embargo, actualmente la amenaza global del cambio climático los pone en grave riesgo, es por ello que el objetivo de este estudio es determinar la variación espacio temporal y climática del humedal altoandino de Chalhuanca (Perú), durante el periodo 1986-2016. Se obtuvieron escenas Landsat de la temporada seca de los años 1986, 1991, 1996, 2001, 2006, 2011, 2016 y mediante técnicas de teledetección se calculó el área y el índice de vegetación (NDVI) de los humedales. Para la precipitación, temperatura máxima y temperatura mínima, se realizó un análisis de medias móviles, tendencias lineales y se aplicó la prueba estadística no paramétrica de Mann-Kendall, finalmente mediante correlación y regresión se evaluó la interacción entre las variables. Los resultados muestran que el área de humedal se ha incrementado en razón de 12 ha/año. En cuanto al NDVI, se ha detectado un incremento de los valores promedio para el periodo evaluado, siendo 0,26 el umbral (promedio de valores mínimos). El análisis de los datos climáticos muestra que la precipitación, temperatura máxima y mínima se han incrementado en 32  mm/dec, 0,3  °C/dec y 0,6  °C/dec respectivamente, siendo significativos (α<0,05) la temperatura máxima y mínima. Por último, los análisis de correlación y regresión muestran que la relación área de humedal-precipitación, NDVI-precipitación y área de humedal-NDVI son significativas para α<0,01, en cambio, la relación área de humedal-temperatura y NDVI-temperatura fueron significativos para α<0,05.[EN] The high Andean wetlands are considered fragile ecosystems that provide ecosystem services for the maintenance of Andean biodiversity and economy. However, currently the global threat of climate change puts them at serious risk, which is why the objective of this study is to determine the spatial-temporal and climatic variation of the high Andean wetlands of Chalhuanca (Peru), during the period 1986-2016. Landsat scenes were obtained during dry season in the years 1986, 1991, 1996, 2001, 2006, 2011, 2016, and using remote sensing techniques the area and vegetation index (NDVI) of the wetlands were calculated. For precipitation, maximum and minimum temperature, an analysis of moving averages, linear trends and the Mann-Kendall non-parametric statistical test was carried out, and finally the interaction between the variables was evaluated by using correlation and regression. The results show that the wetland area has increased by 12 ha/year. As for the NDVI, an increase of the average values for the evaluated period has been detected, being 0.26 the average of minimum values. Analysis of climate data shows that precipitation, maximum and minimum temperature have increased by 32 mm/dec, 0.3 °C/dec and 0.6 °C/dec respectively, with the maximum and minimum temperature being significant (α<0.05). Finally, correlation and regression analyses show that the wetland area-precipitation, NDVI-precipitation and wetland-NDVI relationships are significant for α<0.01, while the wetland-temperature and NDVI-temperature relationships were significant for α<0.05.Esta investigación fue financiada por la Universidad Nacional de San Agustín de Arequipa (UNSA) por contrato N° 047-2016-UNSA dentro del proyecto: “Servicios ecosistémicos de los humedales altoandinos y su contribución en la mitigación de los efectos del cambio climático: estudio de caso”, según contrato de subvención, también, se agradece al Tambo Chalhuanca (Programa Nacional PAIS – Midis), a los pobladores de la localidad de Chalhuanca y a la jefatura de la Reserva Nacional de Salinas y Aguada Blanca (Res. Jef. RNSyAB 002-2018-SERNANP-DGANP-JEF).Pauca-Tanco, A.; Ramos-Mamani, C.; Luque-Fernández, CR.; Talavera-Delgado, C.; Villasante-Benavides, JF.; Quispe-Turpo, JP.; Villegas-Paredes, L. (2020). Análisis espacio temporal y climático del humedal altoandino de Chalhuanca (Perú) durante el periodo 1986-2016. Revista de Teledetección. 0(55):105-118. https://doi.org/10.4995/raet.2020.13325OJS105118055Aguilar, H., Mora, R., Vargas, C. 2014. Metodología para la corrección atmosférica de imágenes Aster, Rapideye, Spot 2 y Landsat 8 con el módulo Flaash del software ENVI. Revista Geográfica de América Central, 53, 39-59. https://doi.org/10.15359/rgac.2-53.2Anderson, E., Marengo, J., Villalba, R., Halloy, S., Young, B., Cordero, D., Gast, F., Jaimes, E., Ruiz, D. 2011. Consecuencias del cambio climático en los ecosistemas y servicios ecosistémicos de los Andes tropicales. En Herzog, S., Martínez, R., Jorgensen, P. y Tiessen, H. (Eds.), Cambio climático y biodiversidad en los Andes tropicales (pp 1-22). Inter-American Institute for Global Change Research (IAI) and Scientific Committee on Problems of the Environment (SCOPE).Aponte-Saravia, J., Ospina, J.E., Posada, E. 2017. Caracterización y modelamiento espacial de patrones en humedales alto andinos, Perú, mediante algoritmos, periodo 1985-2016. Revista Geográfica, 158, 149-170.Báez, S., Jaramillo, L., Cuesta, F., Donoso, D. 2015. Effects of climate change on Andean biodiversity: a synthesis of studies published until 2015. Neotropical Biodiversity, 1(2), 181-194. https://doi.org/10.1080/23766808.2016.1248710Baraer, M., Mark, B., MacKenzie, J., Comdon, T., Bury, J., Huh, K., Portocarrero, C., Gomez, J., Rathay, S. 2012. Glacier recession and water resources in Peru's Cordillera Blanca. Journal of Glaciology, 58(207), 134-150. https://doi.org/10.3189/2012JoG11J186Benavides, J., Vitt, D., Wierder, K. 2013. The influence of climate change on recent peat accumulation patterns of Distichia muscoides cushion bogs in the high-elevation tropical Andes of Colombia. Journal of Geophysical Research: Biogeosciences, 118(4), 1627-1635. https://doi.org/10.1002/2013JG002419Berlanga, C., García, R., López, J., Ruiz, A. 2010. Patrones de cambio de coberturas y usos del suelo en la región costa norte de Nayarit (1973-2000). Investigaciones Geográficas, 72, 7-22.Castino, F., Bookhagenl, B., Strecker, M. R. 2017. Rainfall variability and trends of the past six decades (1950-2014) in the subtropical NW Argentine Andes. Climate Dynamics, 48(3-4), 1049-1067. https://doi.org/10.1007/s00382-016-3127-2Congalton R.G. 1991. A review of assessing the accuracy of classifications of remotely sensed data. Remote Sensing of Environment, 37, 35-46. https://doi.org/10.1016/0034-4257(91)90048-BDangles, O., Rabatel, A., Kraemer, M., Zevallos, G., Soruco, A., Jacobsen, D., Anthelme, M. 2017. Ecosystem sentinels for climate change? Evidence of wetland cover changes over the last 30 years in the tropical Andes. Plos One, 12(5). e0175814. https://doi.org/10.1371/journal.pone.0175814Dong, Z., Wang, Z., Liu, D., Song, K., Li, L., Jia, M., Ding, Z. 2014. Mapping Wetland Areas Using Landsat-Derived NDVI and LSWI: A Case Study of West Songnen Plain, Northeast China. Journal of the Indian Society of Remote Sensing, 42(3), 569-576. https://doi.org/10.1007/s12524-013-0357-1ENVI - Environment for Visualizing Images v5.3. 2019. Harris Geospatial Solutions. Recuperado en setiembre de 2019, disponible en: https://www.harrisgeospatial.com/Estrada, F., Barba, E., Ramos, R. 2013. Cobertura Temporal de los Humedales en la Cuenca del Usumacinta, Balancán, Tabasco, México. Universidad y Ciencia, 29(2), 141-151.García, E., Lleellish, M. 2012. Cartografiado de bofedales usando imágenes de satélite Landsat en una cuenca altoandina del Perú. Revista de Teledetección, 38, 92-118. Recuperado en septiembre de 2019, disponible en: http://www.aet.org.es/ revistas/revista38/Numero38_09.pdfGarcía, E., Otto, M. 2015. Caracterización ecohidrológica de humedales alto andinos usando imágenes de satélite multitemporales en la cabecera de Cuenca del Río Santa, Ancash, Perú. Ecología Aplicada, 14(2), 115-125. https://doi.org/10.21704/rea.v14i1-2.88Guerra, V., Ochoa, S. 2006. Evaluación espacio-temporal de la vegetación y uso del suelo en la Reserva de la Biosfera Pantanos de Centla, Tabasco (1990-2000). Investigaciones Geográficas, 59, 7-25.Haylock, M., Peterson, T., Alves, L., Ambrizzi, T., Anunciacao, M., Baez J., ... Vincent, L. 2006. Trends in total and extreme South American rainfall in 1960-2000 and links with sea surface temperature. Journal of Climate, 19, 1490-1512. https://doi.org/10.1175/JCLI3695.1IBM Corp. Released 2015. IBM SPSS Statistics for Windows, v23.0. Armonk, NY: IBM Corp.Jara, C., Delegido, J., Ayala, J., Lozano, P., Armas, A., Flores, V. 2019. Estudio de bofedales en los Andes ecuatorianos a través de la comparación de imágenes Landsat-8 y Sentinel-2. Revista de teledetección, 53, 45-57. https://doi.org/10.4995/raet.2019.11715Jaramillo, U., Cortés, J., Flórez, C. 2015. Colombia Anfibia. Un país de humedales. Bogotá: Instituto de Investigación de Recursos Biológicos Alexander von Humbolt.Kendall, M.G. 1975. Kendall Rank Correlation Methods. London: Griffin.Larsen, T., Brehm, G., Navarrete, H., Franco, P., Gómez, H., Mena, J., Morales, V., Argollo, J., Blacutt, L., Canhos, V. 2011. Desplazamientos de los rangos de distribución y extinciones impulsados por el cambio climático en los Andes tropicales: síntesis y orientaciones. En Herzog, S., Martínez, R., Jorgensen, P. y Tiessen, H. (Eds.), Cambio climático y biodiversidad en los Andes tropicales (pp. 57-82). Inter-American Institute for Global Change Research (IAI) and Scientific Committee on Problems of the Environment (SCOPE).Mann, H.B. 1945. Non parametric test against trend. Econometrica, 13, 245-259. https://doi.org/10.2307/1907187Maldonado-Fonkén, M. 2014. An introduction to the bofedales of the peruvian high Andes. Mires and Peat, 15(4), 1-13.Marengo, J., Pabón, J., Díaz, A., Rosas, G., Avalos, G., Montealegre, E., Villacís M., Solman S. M., Rojas, M. 2011. Cambio climático: evidencias y futuros escenarios en la región andina. En Herzog, S., Martínez, R., Jorgensen, P. y Tiessen, H. (Eds.), Cambio climático y biodiversidad en los Andes tropicales (pp. 131-150). Inter-American Institute for Global Change Research (IAI) and Scientific Committee on Problems of the Environment (SCOPE).Martínez, A., Rodríguez, J., Cabrera, A. 2014. Los paisajes de humedales, marco conceptual y aspectos metodológicos para su estudio y ordenamiento. Mercator (Fortaleza), 13(2), 169- 161. https://doi.org/10.4215/RM2014.1302.0012Mazzarino, M., Finn, J. T. 2015. An NDVI analysis of vegetation trends in an Andean watershed. Wetlands Ecology and Management, 24, 623-640. https://doi.org/10.1007/s11273-016-9492-0Medina, G., Mejía, A. 2014. Análisis multitemporal y multifractal de la desglaciación de la cordillera Parón en los Andes de Perú. Ecología Aplicada, 13(1), 35-42. https://doi.org/10.21704/rea.v13i1-2.452Mitsch, W., Gosselink, J. 2015. Wetlands. New Jersey: John Wiley y Sons, Inc.Mwita, E., Menz, G., Misana, S., Becker, M., Kisanga, D., Boehme, B. 2013. Mapping small wetlands of Kenya and Tanzania using remote sensing techniques. International Journal of Applied Earth Observation and Geoinformation, 21, 173-183. https://doi.org/10.1016/j.jag.2012.08.010Oñate-Valdivieso, F., Bosque, J. 2011. Estudio de tendencias climáticas y generación de escenarios regionales de cambio climático en una cuenca hidrográfica binacional en América del Sur. Estudios Geográficos, 270(27), 147-172. https://doi.org/10.3989/estgeogr.201107Otto, M., Schreder, D., Richters, J. 2011. Hydrology differentiation and spatial distribution of high altitude wetlands in a semi-arid Andean region derived from satellite data. Hydrology Earth System Science, 15, 1713-1727. https://doi.org/10.5194/hess-15-1713-2011Ozesmi, S.L., Bauer, M.E. 2002. Satellite remote sensing of wetlands. Wetland Ecology and Management, 10(5), 381-402. https://doi.org/10.1023/A:1020908432489Parra, A. Hernández, T., Francisco, L. 2010. Identificación y delimitación de humedales lénticos en el valle alto del río cauca mediante el procesamiento digital de imágenes de satélite. Ingeniería de Recursos Naturales y del Ambiente, 9, 78-88.Pekel, J.F., Cottam, A., Gorelick, N., Belward, A.S. 2016. High-resolution mapping of global surface water and its long-term changes. Nature, 540, 418- 422. https://doi.org/10.1038/nature20584Pérez, M., Llorca, J., Sanz, J. 2007. Evolución de la temperatura superficial desde el siglo XVIII. Nimbus, 19-20, 233-272.Polk, M., Young, K., Baraer, M., Mark, B., McKenzie, J., Bury, J., Carey, M. 2017. Exploring hydrologic connections between tropical mountain wetlands and glacier recession in Peru's Cordillera Blanca. Applied Geography, 78, 94-103. https://doi.org/10.1016/j.apgeog.2016.11.004Ponce, B. 2010. Detección y análisis del cambio de uso del suelo en la zona centro - norte de la provincia de Capitán Prat, XI Región período 1984-2003 (Tesis de grado). Universidad Austral de Chile, Valdivia.Rabatel, A., Francou, B., Soruco, A., Gomez, J., Cáceres, B., Ceballos, J., … Wagnon, P. 2013. Current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change. Cryosphere, 7, 81-102. https://doi.org/10.5194/tc-7-81-2013Robinson, A. B., Robinson, N. E., Soon, W. 2007. Environmental Effects of Increased Atmospheric Carbon Dioxide. Journal of American Physicians and Surgeons, 12, 79-90.Salvador, F., Monerris, J., Rochefort, L. 2014. Peatlands of the Peruvian Puna ecoregion: types, characteristics and disturbance. Mires and Peat, 15(3), 1-17.Salvador, M. 2017. Climap-aplicativo para análise de dados climáticos-versão 3.0. Revista Brasileira de Climatologia, 13(20), 349-374. https://doi.org/10.5380/abclima.v20i0.46351Skansi, M.M., Brunet, J., Sigró, E., Aguilar, J., Groening, O., Bentancur, Y., … Jones, P. 2013. Warming and wetting signals emerging from analysis of changes in climate extreme indices over South America. Global and Planetary Change, 100, 295-307. https://doi.org/10.1016/j.gloplacha.2012.11.004Solman, S., Nunez, M., Cabre, M.F. 2008. Regional climate change experiments over southern South America. I: Present Climate. Climate Dynamics, 30, 533-552. https://doi.org/10.1007/s00382-007-0304-3Seehaus, T., Malz, P., Sommer, C., Lipp, S., Cochachin, A., Braun, M. 2019. Changes of the tropical glaciers throughout Peru between 2000 and 2016 - mass balance and area fluctuations. The Cryosphere, 13, 2537-2556. https://doi.org/10.5194/tc-13-2537-2019Squeo, F., Warner, B., Aravena, R., Espinoza, D. 2006. Bofedales: high altitude peatlands of the central Andes. Revista Chilena de Historia Natural, 79, 245-255. https://doi.org/10.4067/S0716-078X2006000200010Urrutia, R., Vuille, M. 2009. Climate change projections for the tropical Andes using a regional climate model: temperature and precipitation simulations for the end of the 21st century. Journal of Geophysical Research, 114, 1-15. https://doi.org/10.1029/2008JD011021Young, B., Young, K., Josse, C. 2011. Vulnerabilidad de los ecosistemas de los Andes tropicales al cambio climático. En Herzog, S., Martínez, R., Jorgensen, P. y Tiessen, H. (Eds.), Cambio climático y biodiversidad en los Andes tropicales (pp. 195-208). Inter-American Institute for Global Change Research (IAI) and Scientific Committee on Problems of the Environment (SCOPE).Vuille, M., Bradley, R.S. 2000. Mean annual temperature trends and their vertical structure in the tropical Andes. Geophysical Research Letters, 27, 3885-3888. https://doi.org/10.1029/2000GL011871Vuille, M., Bradley, R., Werner, M., Keiming, F. 2003. 20th century climate change in the tropical Andes: observations and model results. Climatic Change, 59, 75-99. https://doi.org/10.1023/A:1024406427519Vuille, M., Keimig, F. 2004. Interannual variability of summertime convective cloudiness and precipitation in the central Andes derived from ISCCP-B3 data. Journal of Climatology, 17, 3334-3348. https://doi.org/10.1175/1520-0442(2004)0172.0.CO;2Vuille, M. 2013. Climate Change and Water Resources in the Tropical Andes. Banco Interamericano de Desarrollo Unidad de Salvaguardias Ambientales. Nota técnica: No. IDB-TN-515.Vuille, M., Franquist, E., Garreaud, R., Casimiro, W., Cáceres, B. 2015. Impact of the global warming hiatus on Andean temperature. 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Evaluation of nitrogen dioxide chemiluminescence monitors in a polluted urban environment

International audienceData from a recent field campaign in Mexico City are used to evaluate the performance of the EPA Federal Reference Method for monitoring the ambient concentrations of NO2. Measurements of NO2 from standard chemiluminescence monitors equipped with molybdenum oxide converters are compared with those from Tunable Infrared Laser Differential Absorption Spectroscopy (TILDAS) and Differential Optical Absorption Spectroscopy (DOAS) instruments. A significant interference in the chemiluminescence measurement is shown to account for up to 50% of ambient NO2 concentration during afternoon hours. As expected, this interference correlates well with non-NOx reactive nitrogen species (NOz) as well as with ambient O3 concentrations, indicating a photochemical source for the interfering species. A combination of ambient gas phase nitric acid and alkyl and multifunctional alkyl nitrates is deduced to be the primary cause of the interference. Observations at four locations at varying proximities to emission sources indicate that the percentage contribution of HNO3 to the interference decreases with time as the air parcel ages. Alkyl and multifunctional alkyl nitrate concentrations are calculated to reach concentrations as high as several ppb inside the city, on par with the highest values previously observed in other urban locations. Averaged over the MCMA-2003 field campaign, the chemiluminescence monitor interference resulted in an average measured NO2 concentration up to 22% greater than that from co-located spectroscopic measurements. Thus, this interference has the potential to initiate regulatory action in areas that are close to non-attainment and may mislead atmospheric photochemical models used to assess control strategies for photochemical oxidants

Comparative study of paediatric prescription drug utilization between the spanish and immigrant population

<p>Abstract</p> <p>Background</p> <p>The immigrant population has increased greatly in Spain in recent years to the point where immigrants made up 12% of the infant population in 2008. There is little information available on the profile of this group with regard to prescription drug utilization in universal public health care systems such as that operating in Spain. This work studies the overall and specific differences in prescription drug utilization between the immigrant and Spanish population.</p> <p>Methods</p> <p>Use was made of the Aragonese Health Service databases for 2006. The studied population comprises 159,908 children aged 0-14 years, 13.6% of whom are foreign nationals. Different utilization variables were calculated for each group. Prescription-drug consumption is measured in Defined Daily Doses (DDD) and DDD/1000 persons/day/(DID).</p> <p>Results</p> <p>A total of 833,223 prescriptions were studied. Utilization is lower for immigrant children than in Spanish children for both DID (66.27 v. 113.67) and average annual expense (€21.55 v. €41.14). Immigrant children consume fewer prescription drugs than Spanish children in all of the therapy groups, with the most prescribed (in DID) being: respiratory system, anti-infectives for systemic use, nervous system, sensory organs. Significant differences were observed in relation to the type of drugs and the geographical background of immigrants.</p> <p>Conclusion</p> <p>Prescription drug utilization is much greater in Spanish children than in immigrant children, particularly with reference to bronchodilators (montelukast and terbutaline) and attention-disorder hyperactivity drugs such as methylphenidate. There are important differences regarding drug type and depending on immigrants' geographical backgrounds that suggest there are social, cultural and access factors underlying these disparities.</p

Reducing corruption in a Mexican medical school: impact assessment across two cross-sectional surveys

<p>Abstract</p> <p>Background</p> <p>Corruption pervades educational and other institutions worldwide and medical schools are not exempt. Empirical evidence about levels and types of corruption in medical schools is sparse. We conducted surveys in 2000 and 2007 in the medical school of the Autonomous University of Guerrero in Mexico to document student perceptions and experience of corruption and to support the medical school to take actions to tackle corruption.</p> <p>Methods</p> <p>In both 2000 and 2007 medical students completed a self-administered questionnaire in the classroom without the teacher present. The questionnaire asked about unofficial payments for admission to medical school, for passing an examination and for administrative procedures. We examined factors related to the experience of corruption in multivariate analysis. Focus groups of students discussed the quantitative findings.</p> <p>Results</p> <p>In 2000, 6% of 725 responding students had paid unofficially to obtain entry into the medical school; this proportion fell to 1.6% of the 436 respondents in 2007. In 2000, 15% of students reported having paid a bribe to pass an examination, not significantly different from the 18% who reported this in 2007. In 2007, students were significantly more likely to have bribed a teacher to pass an examination if they were in the fourth year, if they had been subjected to sexual harassment or political pressure, and if they had been in the university for five years or more. Students resented the need to make unofficial payments and suggested tackling the problem by disciplining corrupt teachers. The university administration made several changes to the system of admissions and examinations in the medical school, based on the findings of the 2000 survey.</p> <p>Conclusion</p> <p>The fall in the rate of bribery to enter the medical school was probably the result of the new admissions system instituted after the first survey. Further actions will be necessary to tackle the continuing presence of bribery to pass examinations and for administrative procedures. The social audit helped to draw attention to corruption and to stimulate actions to tackle it.</p

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London