Enfrentando los desafíos en la evaluación de la participación política

En los estudios sobre participación política se observan diferencias tanto conceptuales como metodológicas relativas a su evaluación que afectan la producción del conocimiento en este campo. Tales diferencias configuran un nivel de complejidad mayor cuando refieren a estudios hechos sobre una misma población. Con el fin de evaluar la participación política de la población cordobesa se desarrollaron 7 estudios en un período de 14 años utilizando diferentes innovaciones metodológicas tendientes a mejorar la calidad de los datos y con el propósito de contribuir a la discusión en torno a la evaluación de este constructo de marcada relevancia social y complejidad. Los resultados reportados son consistentes con la tendencia observada en el campo de estudios que sugiere la complejización de la evaluación de este constructo abarcando su intensidad, amplitud y orientación para conocer de modo más preciso su multidimensionalidad.In studies concerning political participation it is possible to observe both conceptual and methodological differences related to its assessment. These differences affect the production of knowledge in the field. They make up a higher level of complexity when referring to studies done on the same population. In order to evaluate the political participation of the population of Córdoba, 7 studies were developed in a period of 14 years. Different methodological innovations were used in order to improve data quality and with the purpose of contributing to the discussion around the evaluation of this construct of high complexity and social relevance. The results reported are consistent with the trend in this field of studies suggesting the necessity of complexification in the assesment of this construct, encompassing its intensity, amplitude and orientation for knowing more precisely its multidimensionality.Os estudos sobre a participação política são observadas tanto as diferenças conceituais e metodológicas em relação à sua avaliação que afetam a produção de conhecimento neste campo. Essas diferenças tornam-se um maior nível de complexidade quando se referem a estudos realizados com a mesma população. A fim de avaliar a participação política da população Cordoba 7 estúdios foram desenvolvidos ao longo de um período de 14 anos, utilizando diferentes inovações metodológicas destinadas a melhorar a qualidade dos dados e a fim de contribuir para a discussão da avaliação desta construção de forte relevância social e complexidade. Os resultados relatados são consistentes com a tendência no campo dos estudos que sugerem a complexidade da avaliação desse construto que engloba a sua intensidade, amplitude e orientação para saber mais precisamente a sua multidimensionalidade

Intercomparison of spectroradiometers and Sun photometers for the determination of the aerosol optical depth during the VELETA-2002 field campaign

[ 1] In July 2002 the VELETA-2002 field campaign was held in Sierra Nevada ( Granada) in the south of Spain. The main objectives of this field campaign were the study of the influence of elevation and atmospheric aerosols on measured UV radiation. In the first stage of the field campaign, a common calibration and intercomparison between Licor-1800 spectroradiometers and Cimel-318 Sun photometers was performed in order to assess the quality of the measurements from the whole campaign. The intercomparison of the Licor spectroradiometers showed, for both direct and global irradiances, that when the comparisons were restricted to the visible part of the spectrum the deviations were within the instruments' nominal accuracies which allows us to rely on these instruments for measuring physical properties of aerosols at the different measurement stations. A simultaneous calibration on AOD data was performed for the Cimel-318 Sun photometers. When a common calibration and methodology was applied, the deviation was lowered to much less than 0.01 for AOD. At the same time an intercomparison has been made between the AOD values given by the spectroradiometers and the Sun photometers, with deviations obtained from 0.01 to 0.03 for the AOD in the visible range, depending on the channel. In the UVA range, the AOD uncertainty was estimated to be around 0.02 and 0.05 for Cimel and Licor respectively. In general the experimental differences were in agreement with this uncertainty estimation. In the UVB range the AOD measurements should not be used due to maximum instrumental uncertainties

TEMPORAL AND SPATIAL VARIABILITY OF ATMOSPHERIC PARTICLE NUMBER SIZE DISTRIBUTIONS ACROSS SPAIN

This study synthesizes for the first time results from simultaneous aerosol measurements performed at seven diverse locations distributed all over the Spanish geography. The observations were carried out during two field campaigns in 2012–2013, one-month each and during different seasons. These field campaigns were performed in the framework of the Spanish Network of DMAs (REDMAAS) activities. Measurement sites were grouped as polluted sites (urban background) and clean sites (rural background and high-altitude sites). Seasonal differences were more important at polluted sites, mainly related to meteorology and aerosol sources. Higher total particle concentrations were found during the cold period, driven mainly by Aitken-mode particles (traffic-related aerosol particles).This work has been financed by the Ministry of Science and Innovation (CGL2011-15008-E, CGL2010-1777, CGL2011-27020, CGL2014-52877-R, CGL2010-11095-E, CGL2012-39623-C02-01, CGL2014-55230-R & PI15/0051

Intercomparison of spectroradiometers and Sun photometers for the determination of the aerosol optical depth during the VELETA-2002 field campaign

[ 1] In July 2002 the VELETA-2002 field campaign was held in Sierra Nevada ( Granada) in the south of Spain. The main objectives of this field campaign were the study of the influence of elevation and atmospheric aerosols on measured UV radiation. In the first stage of the field campaign, a common calibration and intercomparison between Licor-1800 spectroradiometers and Cimel-318 Sun photometers was performed in order to assess the quality of the measurements from the whole campaign. The intercomparison of the Licor spectroradiometers showed, for both direct and global irradiances, that when the comparisons were restricted to the visible part of the spectrum the deviations were within the instruments' nominal accuracies which allows us to rely on these instruments for measuring physical properties of aerosols at the different measurement stations. A simultaneous calibration on AOD data was performed for the Cimel-318 Sun photometers. When a common calibration and methodology was applied, the deviation was lowered to much less than 0.01 for AOD. At the same time an intercomparison has been made between the AOD values given by the spectroradiometers and the Sun photometers, with deviations obtained from 0.01 to 0.03 for the AOD in the visible range, depending on the channel. In the UVA range, the AOD uncertainty was estimated to be around 0.02 and 0.05 for Cimel and Licor respectively. In general the experimental differences were in agreement with this uncertainty estimation. In the UVB range the AOD measurements should not be used due to maximum instrumental uncertainties

Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus

The rejection of citrus fruit caused by infestations of the California red scale (CRS), Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae), raises concerns about its management. This fact has led to the introduction of new integrated control methods in citrus orchards, including the implementation of techniques based on pheromones. Previous works described efficient mating disruption pheromone dispensers to control A. aurantii in the Mediterranean region. The main aims of the present study were to adjust the timing of dispenser applications and study the importance of controlling the early first generation of A. aurantii by testing two different application dates: before and after the first CRS male flight. The efficacy of the different mating disruption strategies was tested during 2010 in an experimental orchard and these results were confirmed during 2011 in a commercial citrus farm. Results showed that every mating disruption strategy achieved significantly lower male captures in monitoring pheromone traps compared with untreated plots, as well as mean fruit infestation reductions of about 80 %. The control of the first CRS generation is not essential for achieving a good efficacy as demonstrated in two locations with different pest pressure. The late application of MD dispensers before the second CRS male flight has proven to be effective, suggesting a new advantageous way to apply mating disruption.The authors want to thank Fernando Alfaro from Denia, Antonio Caballero, and Javier Macias from Rio Tinto Fruit S.A. (Huelva, Spain) for field support. We also thank Ecologia y Proteccion Agricola SL for the pheromone supply. This work has been funded by the Spanish Ministry of Science and Innovation (project AGL2009-10725) and Agroalimed Foundation. The translation of this paper was funded by the Universidad Politecnica de Valencia (Spain).Vacas González, S.; Alfaro Cañamás, C.; Primo Millo, J.; Navarro-Llopis, V. (2015). Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus. Journal of Pest Science. 88(2):321-329. https://doi.org/10.1007/s10340-014-0623-1S321329882Avidov Z, Balshin M, Gerson U (1970) Studies on Aphytis coheni, a parasite of the California red scale, Aonidiella aurantii in Israel. Biocontrol 15:191–207Barzakay I, Hefetz A, Sternlicht M, Peleg BA, Gokkes M, Singer G, Geffen D, Kronenberg S (1986) Further field trials on management of the California red scale, Aonidiella aurantii, by mating disruption with its sex-pheromone. Phytoparasitica 14:160–161Bedford ECG (1996) Problems which we face in bringing red scale, Aonidiella aurantii (Maskell), under biological control in citrus in South Africa. Proc Int Soc Citriculture 1:485–492Campos-Rivela JM, Martínez-Ferrer MT, Fibla-Queralt JM (2012) Population dynamics and seasonal trend of California red scale (Aonidiella aurantii Maskell) in citrus in Northern Spain. Span J Agric Res 10:198–208Collins PJ, Lambkin TM, Bodnaruk P (1994) Suspected resistance to methidation in Aonidiella aurantii (Maskell) (Homoptera: diaspididae) from Queensland. J Aust Entomol Soc 33:325–326Corma A, Muñoz-Pallares J, Primo-Yufera E (1999) Production of semiochemical emitters having a controlled emission speed which are based on inorganic molecular sieves. World Patent WO9944420Corma A, Muñoz-Pallares J, Primo-Yufera E (2000) Emitter of semiochemical substances supported on a sepiolite, preparation process and applications. World Patent WO0002448DeBach P (1959) New species and strains of Aphytis (Hymenoptera: Eulophidae) parasitic on the California red scale, Aonidiella aurantii (Mask.), in the Orient. 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In: Proceeding 6th International Citrus Congress, Tel Aviv (Israel), pp 1121–1127Hernández-Penadés P, Rodríguez-Reina JM, García-Marí F (2002) Umbrales de tratamiento para cóccidos diaspídidos en cítricos. Bol San Veg Plagas 28:469–478Hothorn T, Bretz F, Westfall P (2008) Simultaneous Inference in General Parametric Models. Biometrical J 50:346–363Ioratti C, Anfora G, Tasin M, De Cristofaro A, Witzgall P, Lucchi A (2011) Chemical ecology and management of Lobesia botrana (Lepidoptera: Tortricidae). J Econ Entomol 104:1125–1137Kehat M, Anshelevich L, Harel M, Dunkelblum E (1995) Control of the codling moth (Cydia pomonella) in apple and pear orchards in Israel by mating disruption. Phytoparasitica 23:285–296Kennett CE, Hoffmann RW (1985) Seasonal development of the California red scale (Homoptera: Diaspididae) in San Joaquin Valley citrus based on degree-day accumulation. J Econ Entomol 78:73–79Levitin E, Cohen E (1998) The involvement of acetylcholinesterase in resistance of the California red scale shape Aonidiella aurantii to organophosphorus pesticides. Entomol Exp Appl 88:115–121Lykouressis D, Perdikis D, Samartzis D, Fantinou A, Toutouzas S (2005) Management of the pink bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) by mating disruption in cotton fields. Crop Prot 24:177–183McLaren IW, Buchanan GA (1973) Parasitism by Aphytis chrysomphali Mercet and A. melinus Debach of Californian red scale, Aonidiella aurantii (Maskell), in relation to seasonal availability of suitable stages of the scale. Austr J Zool 21:111–117Moreno DS, Kennett CE (1985) Predictive year-end California red scale (Homoptera: Diaspididae) orange fruit infestations based on catches of males in the San-Joaquin Valley. 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Reversible Integration of Microfluidic Devices with Microelectrode Arrays for Neurobiological Applications

The majority of current state-of-the-art microfluidic devices are fabricated via replica molding of the fluidic channels into PDMS elastomer and then permanently bonding it to a Pyrex surface using plasma oxidation. This method presents a number of problems associated with the bond strengths, versatility, applicability to alternative substrates, and practicality. Thus, the aim of this study was to investigate a more practical method of integrating microfluidics which is superior in terms of bond strengths, reversible, and applicable to a larger variety of substrates, including microfabricated devices. To achieve the above aims, a modular microfluidic system, capable of reversible microfluidic device integration, simultaneous surface patterning and multichannel fluidic perfusion, was built. To demonstrate the system’s potential, the ability to control the distribution of A549 cells inside a microfluidic channel was tested. Then, the system was integrated with a chemically patterned microelectrode array, and used it to culture primary, rat embryo spinal cord neurons in a dynamic fluidic environment. The results of this study showed that this system has the potential to be a cost effective and importantly, a practical means of integrating microfluidics. The system’s robustness and the ability to withstand extensive manual handling have the additional benefit of reducing the workload. It also has the potential to be easily integrated with alternative substrates such as stainless steel or gold without extensive chemical modifications. The results of this study are of significant relevance to research involving neurobiological applications, where primary cell cultures on microelectrode arrays require this type of flexible integrated solution

In silico pathway reconstruction: Iron-sulfur cluster biogenesis in Saccharomyces cerevisiae

BACKGROUND: Current advances in genomics, proteomics and other areas of molecular biology make the identification and reconstruction of novel pathways an emerging area of great interest. One such class of pathways is involved in the biogenesis of Iron-Sulfur Clusters (ISC). RESULTS: Our goal is the development of a new approach based on the use and combination of mathematical, theoretical and computational methods to identify the topology of a target network. In this approach, mathematical models play a central role for the evaluation of the alternative network structures that arise from literature data-mining, phylogenetic profiling, structural methods, and human curation. As a test case, we reconstruct the topology of the reaction and regulatory network for the mitochondrial ISC biogenesis pathway in S. cerevisiae. Predictions regarding how proteins act in ISC biogenesis are validated by comparison with published experimental results. For example, the predicted role of Arh1 and Yah1 and some of the interactions we predict for Grx5 both matches experimental evidence. A putative role for frataxin in directly regulating mitochondrial iron import is discarded from our analysis, which agrees with also published experimental results. Additionally, we propose a number of experiments for testing other predictions and further improve the identification of the network structure. CONCLUSION: We propose and apply an iterative in silico procedure for predictive reconstruction of the network topology of metabolic pathways. The procedure combines structural bioinformatics tools and mathematical modeling techniques that allow the reconstruction of biochemical networks. Using the Iron Sulfur cluster biogenesis in S. cerevisiae as a test case we indicate how this procedure can be used to analyze and validate the network model against experimental results. Critical evaluation of the obtained results through this procedure allows devising new wet lab experiments to confirm its predictions or provide alternative explanations for further improving the models

Study of the relative humidity dependence of aerosol light-scattering in southern Spain

This investigation focuses on the characterisation of the aerosol particle hygroscopicity. Aerosol particle optical properties were measured at Granada, Spain, during winter and spring seasons in 2013. Measured optical properties included particle light-absorption coefficient (sap) and particle light-scattering coefficient (ssp) at dry conditions and at relative humidity (RH) of 85 +/- 10%. The scattering enhancement factor, f(RH=85%), had a mean value of 1.5 +/- 0.2 and 1.6 +/- 0.3 for winter and spring campaigns, respectively. Cases of high scattering enhancement were more frequent during the spring campaign with 27% of the f(RH=85%) values above 1.8, while during the winter campaign only 8% of the data were above 1.8. A Saharan dust event (SDE), which occurred during the spring campaign, was characterised by a predominance of large particles with low hygroscopicity. For the day when the SDE was more intense, a mean daily value of f(RH=85%)=1.3 +/- 0.2 was calculated. f(RH=85%) diurnal cycle showed two minima during the morning and afternoon traffic rush hours due to the increase in non-hygroscopic particles such as black carbon and road dust. This was confirmed by small values of the single-scattering albedo and the scattering Angstrom exponent. A significant correlation between f(RH=85%) and the fraction of particulate organic matter and sulphate was obtained. Finally, the impact of ambient RH in the aerosol radiative forcing was found to be very small due to the low ambient RH. For high RH values, the hygroscopic effect should be taken into account since the aerosol forcing efficiency changed from -13W/m2 at dry conditions to -17W/m2 at RH=85%.This work was supported by the Andalusia Regional Government through projects P10-RNM-6299 and P12-RNM-2409; by the Spanish Ministry of Economy and Competitiveness through projects CGL2010-18782, CSD2007-00067, CGL2011-13580-E/CLI and CGL2011-16124-E; and by EU through ACTRIS project (EU INFRA-2010-1.1.16-262254).G. Titos was funded by the program FPI of the Spanish Ministry of Economy and Competitiveness – Secretariat of Science, Innovation and Development under grant BES-2011-043721

Mathematical modeling of the dynamic storage of iron in ferritin

<p>Abstract</p> <p>Background</p> <p>Iron is essential for the maintenance of basic cellular processes. In the regulation of its cellular levels, ferritin acts as the main intracellular iron storage protein. In this work we present a mathematical model for the dynamics of iron storage in ferritin during the process of intestinal iron absorption. A set of differential equations were established considering kinetic expressions for the main reactions and mass balances for ferritin, iron and a discrete population of ferritin species defined by their respective iron content.</p> <p>Results</p> <p>Simulation results showing the evolution of ferritin iron content following a pulse of iron were compared with experimental data for ferritin iron distribution obtained with purified ferritin incubated <it>in vitro </it>with different iron levels. Distinctive features observed experimentally were successfully captured by the model, namely the distribution pattern of iron into ferritin protein nanocages with different iron content and the role of ferritin as a controller of the cytosolic labile iron pool (cLIP). Ferritin stabilizes the cLIP for a wide range of total intracellular iron concentrations, but the model predicts an exponential increment of the cLIP at an iron content > 2,500 Fe/ferritin protein cage, when the storage capacity of ferritin is exceeded.</p> <p>Conclusions</p> <p>The results presented support the role of ferritin as an iron buffer in a cellular system. Moreover, the model predicts desirable characteristics for a buffer protein such as effective removal of excess iron, which keeps intracellular cLIP levels approximately constant even when large perturbations are introduced, and a freely available source of iron under iron starvation. In addition, the simulated dynamics of the iron removal process are extremely fast, with ferritin acting as a first defense against dangerous iron fluctuations and providing the time required by the cell to activate slower transcriptional regulation mechanisms and adapt to iron stress conditions. In summary, the model captures the complexity of the iron-ferritin equilibrium, and can be used for further theoretical exploration of the role of ferritin in the regulation of intracellular labile iron levels and, in particular, as a relevant regulator of transepithelial iron transport during the process of intestinal iron absorption.</p

Minimization of Biosynthetic Costs in Adaptive Gene Expression Responses of Yeast to Environmental Changes

Yeast successfully adapts to an environmental stress by altering physiology and fine-tuning metabolism. This fine-tuning is achieved through regulation of both gene expression and protein activity, and it is shaped by various physiological requirements. Such requirements impose a sustained evolutionary pressure that ultimately selects a specific gene expression profile, generating a suitable adaptive response to each environmental change. Although some of the requirements are stress specific, it is likely that others are common to various situations. We hypothesize that an evolutionary pressure for minimizing biosynthetic costs might have left signatures in the physicochemical properties of proteins whose gene expression is fine-tuned during adaptive responses. To test this hypothesis we analyze existing yeast transcriptomic data for such responses and investigate how several properties of proteins correlate to changes in gene expression. Our results reveal signatures that are consistent with a selective pressure for economy in protein synthesis during adaptive response of yeast to various types of stress. These signatures differentiate two groups of adaptive responses with respect to how cells manage expenditure in protein biosynthesis. In one group, significant trends towards downregulation of large proteins and upregulation of small ones are observed. In the other group we find no such trends. These results are consistent with resource limitation being important in the evolution of the first group of stress responses