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Abstract: In Mexico, as in many developing countries, no monetary estimates of road transport externalities exist. The abundant empirical evidence from the developed world appears to show such research reaching maturity. Yet, several barriers to deriving basic estimates among developing countries persist. In this study, we addressed such difficulties for the Mexican context, and by pooling the available data and using well-established methods, we calculated six categories of estimates. The results showed that road transport externalities amount to at least 59.42 (44.8–73.97) billion US dollars per year or 6.24% (4.71–7.77%) of GDP. By component, accidents represented the largest share (28%), followed by congestion (22%), greenhouse gases (21%), air pollution (13%), infrastructure (7%), and noise (9%). By vehicle type, cars had the highest costs per pkm, and buses had the highest costs per vkm. The costs of road transport externalities in Mexico ranked between those of developed and developing regions, but we found some notable differences when comparing the impacts per pkm of the four largest externalities. We discuss such differences and the policy implications of our findings. We also provide suggestions for future research. [Copyright &y& Elsevier]

Abstract: The main goal of this research is to develop and to evaluate a relationship established between Normalized Difference Vegetation Index (NDVI) and crop coefficient (K c) for estimating crop evapotranspiration (ETc) of table grapes vineyards (Vitis vinifera L., cvs. Perlette and Superior) in the semi-arid region of Northwest Mexico. Two consecutive growing seasons (2005 and 2006) of continuous measurements of ETc with the eddy covariance system were used to test the performance of the K c–NDVI relationship. An exponential relation relating K c to NDVI (R 2 =0.63) is proposed and tested here as the basis for calculating ETc. The obtained results indicate that the K c–NDVI approach estimates ETc reasonably well over two growing seasons. The root mean square error (RMSE) between measured and derived ETc from NDVI during 2005 and 2006 were respectively about 0.45 and 0.76mmday−1. Some discrepancies between measured and simulated ETc occurred when NDVI saturates at high values, causing the under-estimation of evapotranspiration. [Copyright &y& Elsevier]

Abstract: This paper uses variation in victimization probabilities and past victimization between individuals living in the same community to shed new light on the costs of crime. I use panel data from the Mexican Family Life Survey for 2002 and 2005 and look at the impact of within-community differences in victimization risk on changes in (avoidance) behavior and time-allocation. My results from fixed effects and instrumental variable estimations point towards a number of behavioral changes, including individuals arming themselves, with marked gender differences in the reactions of individuals. Crime victims also suffer from sleep deprivation indicating welfare losses. [Copyright &y& Elsevier]

Abstract: Irrigation scheduling of fruit trees according to the water balance showed significant differences between locations. In recent years, water status measurements such as leaf water potential have been suggested as irrigation tools in different fruit trees. The aim of this study was to adjust water potential threshold values previously studied and water application approaches that permit the estimation of irrigation requirements of olive trees based on midday stem water potential. The experiments were performed during three seasons (from 2005 to 2007) in two different locations (Badajoz and Ciudad Real) with different weather and cultural conditions. In both locations, the olive orchards were seven years old at the beginning of the experiment but had significantly different canopy development. In Ciudad Real the canopy shaded area at the beginning of the experiment was 15% and the first crop was harvested in 2003. On the other hand, the canopy shaded area of the olive orchard in the Badajoz experiment was 40% and the first crop was harvested in 2001. We therefore considered the Ciudad Real orchard as young and Badajoz as mature. Three different irrigation treatments were compared in both locations: Control treatment with traditional water balance as irrigation scheduling and two treatments in which midday stem water potential (SWP) provided the information about water management. In the midday stem water potential irrigation (WI) treatment the threshold value of SWP was −1.2MPa before the beginning of the massive pit hardening period and −1.4MPa after this date. Finally, in the deficit irrigation (DI) treatment the threshold value of SWP was −2.0MPa throughout the season. In the WI and DI treatments irrigation was applied when SWP reached the threshold value. No significant differences were found between Control and WI in any of the seasons or locations when SWP, leaf conductance, shoot and fruit growth and yield (fruit and oil) were considered. In both locations, the same SWP value in WI treatment resulted in similar water application as the Control treatment. In DI treatment, shoot growth was significantly reduced in both locations in all the seasons. The SWP in DI trees was clearly affected in both locations, while leaf conductance was only reduced in the Badajoz experiment. In the Ciudad Real experiment no significant differences between DI and the other treatments were found in fruit growth, whereas differences were found in Badajoz. However, in Ciudad Real yield in DI treatment was significantly reduced, but not in Badajoz. WI treatment was successful for non-water-stress conditions. On the other hand, DI treatment was a mild water stress treatment which reduced yield only in low covered orchards, but not in the orchards with almost maximum canopy shaded area. [Copyright &y& Elsevier]

Abstract: One and a half years after the worst oil spill in U.S. history, we present the first quantitative assessment on the ecological impact of the spill on the salt marsh habitats along the southeastern Louisiana (LA) coast. This research combined satellite and ground data to quantify the impact of the oil and dispersant on the salt marshes in terms of their photosynthetic capacity and physiological status over a large spatial scale. Two of the most important marsh biophysical characteristics, including distribution of canopy chlorophyll content and above ground green biomass, were monitored across the southeastern LA coast during the salt marsh growing season (May–October) of 2009 (pre-spill) and 2010 (post-spill) in order to compare and isolate the spill impacted areas. The initial assessment showed that there was a significant post-spill increase in areas with reduced biomass and canopy chlorophyll (>400km2) during the 2010 growing season compared to 50–65km2 during the 2009 growing season. Phenological analysis of the post oil-spill data revealed a significant decrease in the magnitude of biomass and canopy chlorophyll during the peak of the 2010 growing season. June was consistently found to be the worst month in terms of salt marsh health across LA over the 2010 phenological cycle followed by the initial signs of recovery along the fringing marsh areas proximal to the shoreline that were first impacted by oil. Interior marsh patches exhibited persistent signs of stress towards the end of the growing season. Extensive reduction in photosynthetic activity was observed during the peak of the growing season, particularly in Plaquemines Parish and St. Bernard Parish. The products generated through this study successfully delineate the critical hotspots of marsh stress so that prioritization of areas needing immediate restoration can be performed. [Copyright &y& Elsevier]

Abstract: This paper presents an estimate of the externalities produced in the Mexico City Metropolitan Area (MCMA) through the impacts on health caused by secondary pollutants attributed to seven electric power plants located outside this area. An original method was developed to make possible a simplified application of the impact pathway approach to estimate the damage costs in the specified area. Our estimate shows that the annual costs attributed to secondary pollutants total 71millionUSD (min/max 20/258millionUSD). Finally, this paper discusses basic ideas on the implications for energy policy arising from this exercise in externality valuation. [ABSTRACT FROM AUTHOR]

Abstract: A novel method based on bilinear time–frequency representations (TFRs) is proposed to determine the time evolution of the linear stability parameters of a boiling water reactor (BWR) using neutronic noise signals. TFRs allow us to track the instantaneous frequencies contained in a signal to estimate an instantaneous decay ratio (IDR) that closely follows the signal envelope changes in time, making the IDR a measure of local stability. In order to account for long term changes in BWR stability, the ACDR measure is introduced as the accumulated product of the local IDRs. As it is shown in this paper, the ACDR measure clearly reflects major long term changes in BWR stability. Last to validate our method, synthetic and real neutronic signals were used. The methodology was tested on the Laguna Verde Unit 1, two events were reported in the Forsmark stability benchmark. [Copyright &y& Elsevier]

Abstract: Lahars are flows composed of water and volcanic sediment which are often dangerous for people living near volcanoes. Therefore, a reliable estimation of lahar volume is needed to effectively assess the risk. This paper proposes a new method to calculate the volume of lahar sediments found in channels of volcanic landscapes. The method requires surveys of several cross-sections along a gorge, a Digital Elevation Model of the study area and measurements of the thickness of the lahar deposits. With these data and a Geographical Information System (GIS), the volume is calculated for the erosive section where deposit volume is divided into oblique parallelepipeds and the sedimentary section where deposit volume is divided into polyhedrons. This new method was applied to the 1997 and 2001 lahars that occurred in the channel of a gorge at Popocatépetl volcano, Mexico. The estimated volumes are 1.85×105 and 1.6×105 m3, respectively, which is about 40% less than those obtained by the traditional method that multiplies lahar flow-path length, sediment width and sediment depth. This observation suggests that the traditional method tends to overestimate volumes. [Copyright &y& Elsevier]

Abstract: Sex assessment is one of the first essential steps in human identification, in both medico-legal cases and bio-archaeological contexts. Fragmentary human remains compromised by different types of burial or physical insults may frustrate the use of the traditional sex estimation methods, such as the analysis of the skull and pelvis. Currently, the application of discriminant functions to sex unidentified skeletal remains is steadily increasing. However, several studies have demonstrated that, due to variation in size and patterns of sexual dimorphism, discriminant functions are population-specific . In this study, in order to improve sex assessment from skeletal remains and to establish population-specific discriminant functions, the diagnostic values of the carpal bones were considered. A sample of 136 individuals (78 males, 58 females) of known sex and age was analyzed. They belong to a contemporary identified collection from the Laboratory of Physical Anthropology, Faculty of Medicine, UNAM (Universidad Nacional Autónoma de México, Mexico City). The age of the individuals ranged between 25 and 85years. Between four and nine measurements of each carpal bone were taken . Independent t-tests confirm that all carpals are sexually dimorphic. Univariate measurements produce accuracy levels that range from 61.8% to 90.8%. Classification accuracies ranged between 81.3% and 92.3% in the multivariate stepwise discriminant analysis. In addition, intra- and inter-observer error tests were performed. These indicated that replication of measurements was satisfactory for the same observer over time and between observers. These results suggest that carpal bones can be used for assessing sex in both forensic and bio-archaeological identification procedures and that bone dimensions are population specific. [Copyright &y& Elsevier]