The 2004 Madrid train bombings: an analysis of pre-hospital management

The terrorist train bombings in Madrid, Spain, on 11 March 2004 triggered a swift and massive medical response. This paper analyses the pre-hospital response to the attacks to gain insight into current trends in disaster management among Madrid's Emergency Medical Services (EMSs). To this end, the existing emergency planning framework is described, the basic structures of the different EMSs are presented, and the attacks are briefly depicted before consideration is given to pre-hospital management. Finally, an explanation of the main underlying misconceptions in emergency planning and management in Madrid is provided to aid understanding of the origins of some of the problems detected during the response. These are attributable mainly to inappropriate planning rather than to mistakes in field-level decision-making. By contrast, many of the successes are attributable to individual initiatives by frontline medics who compensated for the lack of clear command by senior managers by making adaptive and flexible decisions.     

Assessing dimethoate contamination in temperate and tropical climates: potential use of biomarkers in bioassays with two chironomid species

This study was conducted to investigate the potential use of biomarkers in bioassays with chironomids to assess contamination by pesticides in temperate and tropical climates. Two species of midge were studied, the widespread Chironomus riparius and the tropical Kiefferulus calligaster (Kieffer, 1911). Preliminary studies included investigations of the effects of temperature on larval development and the influence of larval age on normal variability of cholinesterase (ChE) and glutathione S-transferase (GST) activities and protein content. In the second phase, the influence of two abiotic factors particularly important in tropical conditions (temperature and oxygen concentration) and of the organophosphorous (OP) insecticide dimethoate on biochemical and conventional endpoints was investigated. Results showed that K. calligaster is morphologically and physiologically similar to C. riparius and for both, the time of larval development decreases with the increase of temperature. Moreover, 3rd and 4th instars appeared to be the most suitable for biomarkers determinations. ChE activity seems to be valuable biomarker regarding temperature and dissolved oxygen (DO) variations, while some caution should be taken when using GST as an environmental biomarker, since it shows some dependence of these parameters. C. riparius was more sensitive to dimethoate than K. calligaster suggesting that the use of bioassays with the former species in tropical conditions may overestimate the toxicity of OP pesticides to autochthonous species. When testing sub-lethal effects of dimethoate to C. riparius, ChE activity showed to be a very sensitive parameter detecting significant effects at the lowest concentration that caused emergence delay of larvae, suggesting that it is an ecologically relevant parameter.     

Kinetic and adsorption study of acid dye removal using activated carbon

The adsorption of three acid dyes, Acid Red 97, Acid Orange 61 and Acid Brown 425 onto activated carbon was studied for the removal of acid dyes from aqueous solutions at room temperature (25 degrees C). The adsorption of each dye with respect to contact time was then measured to provide information about the adsorption characteristics of activated carbon. The rates of adsorption were found to conform to the pseudo-second-order kinetics with a good correlation. The experimental isotherms obtained, except for Acid Orange 61 studied in mixture, were of the S-type in terms of the classification of Giles and co-workers. The best fit of the adsorption isotherm data was obtained using the Freundlich model. When a comparative study was made of the results obtained with single and mixed dyes, it can be seen that some of them affect others and modify their behavior in the adsorption process. The results indicate that activated carbon could be employed for the removal of dyes from wastewater.     

Effect of coumaphos on cholinesterase activity, hematology, and biochemical blood parameters of bovines in tropical regions of Mexico

To assess the effect of coumaphos [O-(3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7-yl) O,O-diethyl phosphorothioate] exposure on physiological responses during bovine production, acetylcolinesterase (AChE) and butyrylcholinesterase (BuChE) activities were measured in whole blood, erythrocytes, and plasma of healthy male steers (Bos Taurus x Bos indicus) sprayed with coumaphos at a non-lethal dose of 1 mg kg(- 1) body weight per day once every 14 (in vivo group) or 21 days (southern and central groups). Coumaphos topically administered at 1 mg/kg body weight per day to cattle under normal management practices in tropical areas produced a significant inhibition in erythrocyte (RBC) AChE and BuAChE activities when compared to baseline levels. RBC-AChE activity for the in vivo group decreased 71.3% (P < 0.05) and BuChE activity 59.1% (P < 0.05); RBC-AChE activity decreased 55.1% (P < 0.05) (southern group) and 43.4% (P < 0.05) (central group). Compared to the control specimens, steers from in vivo, southern, and central groups after 150 days of exposure had lower (P < 0.05) leukocyte count, absolute lymphocyte, erythrocyte, and platelet counts. Decreases in RBC-AChE activities correlated with decreased lymphocyte (r = 1.000, p = 0.01), erythrocyte (r = 1.000, p = 0.003), and platelet counts (r = 0.841, p = 0.036). Significantly increased BUN levels (P < 0.05) correlated with the decrease in RBC-AChE activities (r = - 0.997, p = 0.047) and with the decrease in absolute red blood cell (r = - 0.883, p = 0.020) and lymphocyte (r = - 0.825, p = 0.043) counts; increased (P < 0.05) total plasma protein levels correlated with the decrease in RBC-AChE activities (r = -0.998, p = 0.043), absolute red blood cell (r = - 0.998, p = 0.040), lymphocyte (r = - 0.893, p = 0.017), and platelet (r = -0.855, p = 0.030) counts. The physiological responses correlated with the erythrocyte acetylcholinesterase inhibition could be considered as early indicators or warning responses of bovine exposures to organophosphorus pesticides (OPs).     

Combined effect of diuron and simazine on photosystem II photochemistry in a sandy soil and soil amended with solid olive-mill waste

Diuron (3-(3,4-dichlorophenyl)- = 1,1-dimethylurea) and simazine (6-chloro-N(2), N(4)-diethyl-1,3,5-triazine-2,4-diamine) are soil-applied herbicides used in olive crops. The objective of this study is to investigate the effect of these herbicides on Photosystem II photochemistry of Olea europaea L., and whether the amendment of soil with an organic waste (OW) from olive oil production industry modifies this effect. For this purpose, herbicide soil adsorption studies, with unamended and OW-amended soil, and chlorophyll fluorescence measurements in adult olive leaves, after one, two and three weeks of soil herbicide treatment and/or OW amendment, were performed. Soil application of these herbicides reduced the efficiency of Photosystem II photochemistry of olive trees due to chronic photoinhibition, and this effect is counterbalanced by the addition of OW to the soil. OW reduces herbicide uptake by the plant due to an increase in herbicide adsorption.     

Effect of Fe (III) on acid degradation of methylparathion

A study was undertaken to determine the transformation kinetic of methylparathion (O, O, -dimethyl O-4 nitrophenylphosphorotioate) in the presence of Fe(III) between pH 2 and 7. The Fe(III) was not electroactive under the conditions used in this study, and polarographic signals were exhibited by methylparathion and main degradation product only. Data suggest that hydrolysis of methylparathion in an acid medium is catalyzed by Fe(III) and the pesticide did not degrade in this medium without this cation. Methylparathion degradation was observed at all the pHs studied and was independent of the predominant chemical form of Fe(III) in the aqueous medium. The reaction was first-order with pH-dependent rate constant (k) values ranging from 3.3 x 10(- 3) h(- 1) to 7.0 x 10(- 3) h(- 1). The k values increased as pH decreased, suggesting that Fe(III) acted as an electrophile in the reaction mechanism.     

Structure of Mn-Zr mixed oxides catalysts and their catalytic performance in the gas-phase oxidation of chlorocarbons

The catalytic activity and selectivity of manganese zirconia mixed oxides were evaluated for the oxidation of two common chlorinated pollutants found in waste streams, namely 1,2-dichloroethane (DCE) and trichloroethylene (TCE). Mixed oxides with varying Mn-Zr content were prepared by coprecipitation via nitrates, and subsequent calcination at 600 degrees C for 4 h in air. These catalysts were characterised by means of several techniques such as atomic emission spectrometry, N2 adsorption-desorption, powder X-ray diffraction, temperature-programmed desorption of ammonia, pyridine adsorption followed by diffuse reflectance infrared spectroscopy and temperature-programmed reduction with hydrogen. The active catalytic behaviour of Mn-Zr mixed oxides was ascribed to a substantial surface acidity combined with readily accessible active oxygen species. Hence, the mixed oxide with 40 mol% manganese content was found to be an optimum catalyst for the combustion of both chlorocarbons with a T50 value around 305 and 315 degrees C for DCE and TCE oxidation, respectively. The major oxidation products were carbon dioxide, hydrogen chloride and chlorine. It was observed that the formation of both CO2 and Cl2 was promoted with Mn loading.     

Urbanisation and flood vulnerability in the peri-urban interface of Mexico City

Chronic flooding in the Chalco valley, state of Mexico, Mexico, is the outcome of past and present socio‐environmental changes which have taken place in Mexico City's south‐eastern peri‐urban interface. This flooding is the result of a complex interaction between urbanisation in an ex‐lacustrine area, permanent ecological deterioration and ground subsidence, poor sanitation and inadequate policy responses. Far from solving the flooding problem, short‐term policy responses have created increasingly unsafe conditions for current residents. A socio‐historical analysis of disasters reveals the importance of taking into consideration particular social actors and institutions in hazard generation and flood vulnerability over time. This paper analyses three aspects of this flooding: first, the importance of approaching floods from a socio‐historical perspective; second, the relation between urbanisation, former policies and flood risk generation; and third, current policy responses to and the failure in the risk management of La Compañía Canal.     

Plant senescence: a mechanism for nutrient release in temperate agricultural wetlands

The beneficial uptake of nutrients by wetland plants is countered to some extent by nutrient release back into the aquatic environment due to vegetative die-back. This current study examined whether Leersia oryzoides, a common wetland plant, exhibits luxury uptake of nutrients from simulated farm runoff. The study also tested whether with subsequent decomposition, these nutrients are released back into the water column. When exposed to elevated (>2mg/L N and P) runoff, L. oryzoides assimilated significantly higher concentrations of nitrogen (p<0.001) and phosphorus (p<0.001) in above-ground biomass as compared to non-enriched treatments (<0.05 mg/L N and P). Subsequently, senescence of enriched above-ground biomass yielded significantly higher concentrations of phosphorus (2.19+/-0.84 mg P/L). Using L. oryzoides as our model, this study demonstrates nitrogen and phosphorus sequestration during the growing season and release of phosphorus in the winter.     

Dynamic responses of photosystem II in the Namib Desert shrub, Zygophyllum prismatocarpum, during and after foliar deposition of limestone dust

The effects of limestone dust deposition on vegetation in desert ecosystems have not yet been reported. We investigated these effects in a succulent shrub from the Namib Desert at a limestone quarry near Skorpion Zinc mine (Namibia). Effects of limestone dust were determined in Zygophyllum prismatocarpum (dollar bush) plants with heavy, moderate and no visible foliar dust cover by means of chlorophyll a fluorescence measurements. Limestone dust deposition decreased overall plant performance through loss of chlorophyll content, inhibition of CO(2) assimilation, uncoupling of the oxygen-evolving complex and decreased electron transport. Importantly, dynamic recovery occurred after termination of limestone extraction at the quarry. Recovery was accelerated by rainfall, mainly because of dust removal from leaves and stimulation of new growth. These results indicate that limestone dust has severe effects on photosynthesis in desert shrubs, but that recovery is possible and that, in arid environments, this process is modulated by rainfall.