Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

We analyzed the geomorphological heritage of Sierra del Aramo, located in the Asturian Central Massif (Cantabrian mountain range), in northwest Spain, just 20 km southwest of Oviedo, capital of the Principality of Asturias. Sierra del Aramo constitutes a mid-altitude calcareous range (Gamoniteiru Peak, 1791 m a.s.l. and Xistras, 1766 m a.s.l.); from the geological perspective, it is part of the Cantabrian zone, particularly of the Folds and Mantles Region. It extends along 15 km with an NNW-SSE direction, separating the basins of the rivers Trubia to the west and Caudal to the east. The main objective of this research focuses is to list, select and evaluate the Sites of Geomorphological Interest (LIGm), or geomorphosites, to diagnose the condition and potential of these resources, which is essential for proper land-use planning.The methodology used consisted of the application of several analytical approaches related to LIGms or geomorphosites, from which at least six successive phases are recognized. First, we conducted a geomorphological characterization and constructed a detailed geomorphological map at 1:25,000 scale. The second phase consisted in the listing and geomorphological classification of landforms into sets, units, and elements. From these, we selected the main LIGms to identify the most relevant landforms and sorted them according to locations or elements and into unique or representative, to establish the definitive list of LIGms. The fourth phase consisted of a detailed description of the core values of each LGIm or geomorphosite. Fifth, we evaluated each geomorphosite based on three values: intrinsic or scientific, added or cultural, and use and management. Finally, an overall assessment of the geomorphosites was conducted based on the score obtained, which supported their classification into three types: high, medium, and low value.As a result of this research, we identified a rich geomorphological heritage was identified in Sierra del Aramo, namely morphostructural and karstic, composed of 4 sets, 17 units, and 27 elements. Six relevant geomorphosites are worth mentioning: Cuesta de Riosa, La Coruxeda-Las Xanas, Angliru, Gamoniteiro, Braña Linares, and Movimiento en masa de Bermiego; the first two obtained an outstanding score, while the others got a medium score.  In general, all these geomorphosites are of exceptional aesthetic-landscape quality. In addition, accessibility to the six LIGms is very good, thanks to the network of regional and local roads (AS-228, MO-5, QU-6, RA-1, RI-5), tracks and trails, some of them cataloged (PR-143, G-106, G-109, G-207). These allow the conduct of the current economic activities, especially livestock ranching (mainly bovine for meat production) and outdoor leisure activities (walking, hiking, mountain ski), with limited impacts.The potential for the use and management of the six geomorphosites is exceptionally high given the excellent conservation status of the traditional landscape and the high interest it motivates, both scientific-didactic and landscape-aesthetic. A high proportion of the area analyzed is part of Montes de Utilidad Pública (No.260, no.309), which would allow initiatives led by public administrations. In fact, these area ideal places for the implementation of projects addressing the interpretation of the geomorphological heritage for educational and geoturism uses. However, in order to avoid potential losses of the high heritage values of Sierra del Aramo, the flow of visitors and intensity of use should be properly managed through official regulations issued to preserve the natural heritage.

Modeling and spatial analysis led to improved management of the integrity of pipelines of hazardous liquids because it facilitates the identification and classification of sections of oil pipelines according to the extent of environmental affectation that may result from a potential spillage. Although analytical tools based on Geographic Information Systems are available for the identification of sections of pipelines, these fail to prioritize properly the management activities related to pipeline integrity, as the results thereof do not include an integrated analysis of the territory. This article outlines a methodology that combines spatial data on population, environmentally sensitive areas, infrastructure, streams, route of pipelines transporting hydrocarbons, to identify the indirect consequences of leakage of transported liquids. Our findings provide information related to the impact of spills, which are easily integrated to methodologies for integrity management based on risk analysis. The methodology is based on the use of the Hierarchical Analysis Process (PAJ, in Spanish) and the calculation of the Minimum Cumulative Cost (CMA) to group together points along pipelines with simultaneous impacts involving several heavily affected areas. PAJ defines each at-risk element in the territory and determines the relative vulnerability by calculating weighting factors. The CMA is calculated from the element of interest to each point in the pipe; this process leads to identifying the proximity between them based on a surface spill. The transportation cost is used mainly to modify the vulnerability as a function of distance, so that vulnerability decreases with increasing distance and the cost of transportation from the pipeline. Implementation requires the design of cartographic models to describe data processing and analysis and spatial information. The cartographic models designed include spatial analysis processes for calculating cost maps, CMA, algebraic overlay, and estimates of impact levels for specific pipeline points. PAJ contemplates the fulfilment of four phases: the first defined as an issue the need to classify pipelines according to the extent of environmental and social consequences. The second identified vulnerable elements in the territory and proposed a hierarchical three-level structure. The third set paired-comparison matrices, and calculated the weighting factors for each element at each level of the hierarchical structure with the Delphi method and a panel of experts. The fourth calculated the weighting factors for the last level using comparison values for intermediate pairs (Saaty, 2008). The spatial representation of the CMA of the spill requires a map of surface transport cost considering transport at ground level and through rivers. For ground transport, we used Manning’s equation assuming very wide rectangular cross sections (flat and convex plots) and parabolic sections (concave plots). For river transport, we included a constant k, which is higher than 1 for costs associated with water flows; this allows simulating the increased spill rate when transported by rivers. CMA represents the shortest time needed for a spill to travel the distance between the pipeline and any of the elements analyzed in the territory. The data required for calculation with the ArcGIS software are the map of costs, the digital elevation model, and vertical and horizontal cost factors. The layers of standardized minimum cost are overlaid algebraically using the weighting factors calculated previously. Finally, values are assigned to each point on the route of the pipeline. The proposed methodology offers significant advantages compared to traditional methods regarding the identification of sections that impact heavily affected areas. The implementation of cartographic models yielded a classification of pipeline points, considering an analysis that integrates environmental and social aspects of the territory. On the other hand, the impact index, expressed in a range of 0 to 1, can be easily integrated to risk assessment matrices in pipeline integrity management programs. Finally, the methodology is flexible and can be reproduced in other geographic areas with differing social and environmental characteristics. 

Rationing of working capital in rural businesses that work in agriculture is preventing from improving living conditions in impoverished areas. Whereas government programs have their greatest impact in areas attempting to transition from subsistence production into a modern commodity production system, the attempts to achieve social goals produce varying regional impacts and do not necessarily reach the agricultural households most in need. As a response, Mexican government has established public programs that back small rural enterprises when doing financial operations with private entities.It is well documented that small rural businesses suffer from commercial credit rationing due to inherent risks of their economic activities. Lack of collaterals, credit history or formal accounting records are some of the factors that the private banks avoid credit operations with this kind of producers. Mexican government has established a set of public programs to promote rural economic development through credit guarantees. These guarantees reduce the counterpart risk in credit operations making rural businesses more attractive to private banks. However, the eligibility conditions of this credit guarantee schemes (CGS) can discriminate and leave out the most poor. Adjustments to such programs have been implemented to provide focalized support to the poorest regions of the country. A new set of eligibility rules were issued in 2008 through a new program called Fondo Nacional de Garantías or FONAGA. Even though there is an increase in the number guaranteed operations after the inception of FONAGA, the spatial distribution of the CGS has not been evaluated. Calculating a Gini coefficient as a measure of inequality between the income coming from guaranteed credits and the population with the most patrimony poverty shows that the distribution has been uneven across the country.This study use Geographic Hot Spot Analysis (HSA) to analyze clustering patterns of the CGS distribution before and after the incorporation of FONAGA in 2008. The analysis calculates the Getis-Ord Gi* statistic, an association measure based on spatial conceptualizations such as fixed distances among neighbors. Maximization of spatial clustering reports the areas that consistently received high or low amounts of CGS operations. A high number of CGS operations within contiguous municipalities suggests a hot spot while low number of credit guarantees within municipal neighbors poses a “cold spot” difficulty. The Mexican case offers an opportunity to study a public program that is subject to socio-economic conditions that arise from contrasting commercial relationships with developed economic partners at the north border and emergent economies at the south.HSA reveals that introduction of FONAGA resulted in a major shift of program support that favored smaller scale agriculturalists located in previously underserved and underdeveloped regions of Mexico. In 2004, heavy guarantee coverage was concentrated in northern states of the country. Municipalities from Tamaulipas, Nuevo Leon, Coahuila, Sonora, Baja California, and Baja California Sur were covered by higher amounts of guarantees than the rest of Mexico. On the other end, Oaxaca and Veracruz received consistently low coverage per square km of cultivable land. From 2004 to 2007 there are consistent and statistically significant clustering patterns in the north (hot spots) and south-central (cold spots) and hot spots appeared in the northwest region in 2006. In 2008, the year when FONAGA started operations, the patterns changed significantly. Operations moved from northern to western and southeastern municipalities. In 2009 and 2010 a high number of guaranteed operations increased the allocation intensity in the municipalities of the states of Quintana Roo, Campeche and Yucatan. In general, the hot spots shifted from the north to southern regions in the 2008-2013 period. A combination of a high number of operations with high credit coverage amounts in the southeast region is associated to a downward shift of the average amount CGS per operation, meaning that small-scale farmers in greater need were included in the guarantee schemes after FONAGA took place primarily in the states of Campeche, Yucatan, Quintana Roo, and Chiapas.Until now this type of analysis has not been used to evaluate the targeting of CGS operations. Its application provides a different and important perspective regarding CGS performance. A shift in the CGS allocation after the introduction of FEGA in 2008 represents a success from the view point of the trust administrator. However, clustering patterns are evidence of a continuing uneven distribution of the credit guarantees. This points to the need of more analysis for public programs implementation to explore additional ways to provide financial access to rural businesses that do not have private funding.

This study addresses two research questions. Does Bus Rapid Transit (BRT) constitute a new paradigm of urban mobility? Is it convenient to implement BRT approaches in any city regardless of its size and especially without considering the negative externalities that these approaches have upon urban functionality?Given the inability of quantitative and qualitative methods to separately explain transportation problems in large metropolitan areas, this research is carried out considering methodological triangulation, as a good alternative to visualize a problem from different angles, considering that if two strategies provide very similar results, then it is viable to corroborate their findings, but if the opposite happens, their results could be discarded. In addition, the present research is developed from an urban geography approach, evaluating the implementation and functionality of BRTs on a global scale, according to different regions and cities necessities.The systems of BRT were born in Curitiba Brazil back in 1974, combining the bus-ways of Chicago with Metro stations, nevertheless, at the moment, there are few investigations that question the paradigm shift from urban trains to BRT buses. The truth is that BRTs have spread rapidly in much of the world, under the impulse and interests of several Non Governmental Organizations (NGOs), civil associations, or private companies that encourage the governments of low and middle-income countries to implement them, based on short-term costs without considering the long-term consequences of their operation on metropolitan transport systems.Historical evidence indicates that in large cities within the developed regions of the world (such as Western Europe and East Asia), the solution to the problems of transport and universal mobility is based on the combination of non-motorized travels and multi-modal mass transport that circulates through rail networks which are independent of urban roads.On the other hand, in megacities of more than 10 million inhabitants, in developing countries such as Mexico, BRTs approaches have been promoted with little success, as a uni-modal solution, which is not considered as an important factor of an inter-modal transport system built to discourage excessive use of auto-mobiles and low-capacity public transport; to improve metropolitan accessibility; to reduce the use of fossil fuels; to reduce the phenomena of congestion, pollution, road insecurity and the deterioration of urban heritage.Undoubtedly, BRTs work ideally as a semi-massive mode of transport for medium-sized cities. However, it is a mistake to want to introduce them as uni-modal solutions for roads with elevated passenger demand in highly populated cities like Mexico. The change of paradigm from urban trains to BRTs in Mexico and Latin America in general, must be carefully analysed before its implementation. The results offered by trying to replace multi-modal mass transport networks with uni-modal networks of limited capacity, in the most populated metropolitan areas of the world, have not generated the expected benefits in terms of urban mobility. Several Latin American cities have applied BRTs approaches, but they still provide evidence of very high levels of pollution, congestion and extensive consumption of public space for transportation purposes. They even register severe threats of collapse, not only in their own networks, but also in metropolitan roads.In general, it is recommended that BRTs must play the role of a supplier to high capacity multi-modal transportation networks, such as the Metro, Trams, Light Trains and Suburban Trains, because the latter are the only modes of transport that have the capacity to satisfy most of the metropolitan trips and to offer unique economic, social and environmental benefits. The aforementioned benefits will continue to increase along with the size of the cities providing these means of transport.It is concluded that high capacity urban train networks can share the top of the new "mobility pyramid" along with pedestrians and cyclists, because these are the most efficient modes of transport in order to free urban roads from the auto-mobiles and the low capacity public transport. Finally it is worth mentioning that its implementation and functionality should be promoted so that to reduce congestion, the emission of pollutants and traffic accidents, without having to drastically reduce the number of trips.

Complete time series with no missing values are essential for reliable scientific-geographic analyses. Temperature time series commonly show data gaps, particularly in meteorological stations located in regions with few scattered stations. Scarce meteorological stations exist in the arid central-western region of Argentina, where vast, sparsely populated, or unproductive areas far away from major urban centers and oases may have restrained the installation of sufficient stations. Thus, climate data records from existing stations, especially those in rural areas, often lack temporal continuity, and the data gaps have to be filled in based on data from adjacent stations. However, this is not possible in the absence of nearby stations with reliable and sufficiently long records that can be used for estimating the missing data. This study aimed to develop an easy-to-apply, highly accurate operational method to fill data gaps in monthly temperature time series, which is particularly suitable for locations with no nearby meteorological stations. The method developed herein is based on the use of annual and monthly means and the overall time series average. The method was tested on the 46-yr time series of monthly temperature data recorded at the meteorological station of San Juan Aero (base station), located in the Province of San Juan, central-western Argentina. The base station is close to two other weather stations whose data were used to validate the results of one of the phases of the method. The study included: a) the application of the method proposed to the San Juan Aero station (base station) using subsets of varying lengths of the entire time series data set, and comparing the accuracy of the estimates thus obtained by means of ad hoc indices; b) the application of the same procedure used in a), but with varying percentages of missing data; c) the comparison of the missing values estimated by the method developed herein versus those estimated using conventional methods based on data from adjacent stations, and d) the application of the method developed herein to a meteorological station located outside the study area under different climate and environmental conditions.   The method was used to estimate missing monthly temperature values for the 46-yr time series recorded in the San Juan Aero station. Tests were run to determine the percentage of missing data (5%, 10%, and 15%) with which the method yields the best fit. The efficiency of the Ti method was compared versus three traditional methods (arithmetic mean, normal proportion, and inverse distance weighting) that impute the missing values from data recorded at nearby stations. Finally, based on the results from the previous stages, the Ti method was applied to a test station located some 150 km from the baseline station to determine whether it can also be applied to meteorological stations located outside the study region, under different physical environmental characteristics. The results showed that the Ti method works better on meteorological stations having at least 30-yr records and no more than 10% missing data; under these conditions, its estimates are more accurate that those yielded by the three traditional methods tested and can be reliably applied to stations located outside the study region under different physical and environmental conditions. The limitations of the Ti method are worth mentioning: it cannot be used when the baseline station records have a data gap longer than one full year, or when data for the same month are missing for two consecutive years. Given the results yielded by this method and taking into account the limitations mentioned above, compared to other methods that use data from nearby stations, we recommend using the Ti method to estimate missing monthly temperature values for meteorological stations lacking nearby stations. Compared to the traditional methods tested, the Ti method seems highly valuable as a tool to fill missing data in temperature time series from isolated weather stations, which then could be used for climate analyses of remote zones.

Los homicidios son un problema prioritario de seguridad pública en México, dada la magnitud e impacto que los caracteriza; sin embargo, raramente se estudian como causa de muerte y hecho violento desde una perspectiva geográfica y de salud pública. A partir de fuentes secundarias (prensa escrita y medios electrónicos) se llevó a cabo un análisis comparativo de homicidios ocurridos en 2013 y 2018 por colonias y municipios del Área Metropolitana de Guadalajara (AMG), Jalisco; los homicidios fueron georreferenciadas considerando el lugar donde ocurrió la agresión  y analizados mediante medidas de tendencia central y dispersión con el objetivo de determinar la magnitud, distribución y tendencia espacial. Como resultado, de 2013 (n= 465) a 2018 (n= 988) la cantidad de homicidios ocurridos en el AMG aumentó, salvo en el municipio de Zapopan. En consecuencia, en 2018 la tasa de homicidios osciló entre 6.2 (Tonalá) y 50.7 por 100 mil (Tlajomulco de Zúñiga), un incremento hasta 4 veces mayor respecto al 2013. Además, el número de homicidios analizado se concentró territorialmente en el 16% (2013) y 24% (2018) del total de colonias del AMG, desplazándose del noroeste-sureste hacia el norte-sur, respectivamente. En este sentido, los resultados implican la identificación de las colonias de mayor riesgo de homicidio. Por lo tanto, en estas zonas es donde se requiere (re) dirigir y mejorar políticas públicas para modificar factores de riesgo, actividades o comportamientos ilícitos que generalmente preceden la ocurrencia de homicidios.

Most methods for estimating the morphometric values of water bodies use equations derived from hypsographic curves or digital terrain models (DTMs) that relate depth, volume (V), and area (A) and that model the uncertainty inherent in the complex underwater morphology. This research focuses directly on the use of topobathymetric models that include the bathymetry and topography of the surrounding area next to the water body. The projection of the water surface height (H) on each DTM pixel generates a water column with intrinsic attributes such as volume and area. The process is replicated among all cells and estimates the total area and volume of the water body. If the V or A is the input data, an algorithm that iterates height values is used to generate the new data, which is compared with the entered value that functions as a reference. If the difference between the reference value and the calculated value is less than an error threshold, the iteration stops, and the maximum and average depths are calculated. The raster and the shape that represent the body of water are created. The cross comparison of H-V-A showed that there is an error between 0.0034% and 0.000039% when any of the parameters are used as input data. Performance tests determined that pixel dimensions are directly proportional to the processing time for each iteration. The results of the implementation of this algorithm were satisfactory since, for the DTM of Bustillos Lagoon, Chihuahua, Mexico, the simulation took less than 17 seconds in at most 22 iterations.

This work presents the experience of Participatory Community-based Monitoring (PCM) of water in a forestry community in the southwest periphery of Mexico City, carried out during 2015-2017 by a collaborating team (academy-community). Based on the conceptual framework of PCM, several stages of the study are developed: i) monitoring of water in the forest area (sources of drinking water supply), ii) measurements in the urban part of the community (homes and tanks of storage), iii) the application of a survey on social perception of water service, and iv) the sampling of water quality for the laboratory (to corroborate the rigor of the data taken through the PCM). A tendency of preservation of good physicochemical quality of water is observed, with a severe bacteriological problem; on the other hand, there is a social conscience about poor resource endowment and the need for forest conservation. Finally, we reflect on the need to implement pollution control measures and on the usefulness of the PCM for social empowerment and community decision making for territorial planning at local scale.

Different theoretical, electrochemical and surface techniques were applied to study the corrosion inhibition effects of 2-Amino-6-hydroxybenzothiazole in 5% HCl solution. The density functional theory was carried out and quantum chemical factors like the energy gap, energy of highest occupied molecular orbital, the energy of lowest unoccupied molecular orbital, the fraction of electron transferred, and Mulliken charges have been calculated. In addition, according to quantum calculation, S atom in 2-Amino-6-hydroxybenzothiazole indicated more tendency for electrophilic attack in adsorption. The main reason for high inhibition efficiencies in very low concentrations is the planar and simplicity of inhibitor structure which leads to increasing the efficiency of adsorption by functional group especially sulfur. Electrochemical frequency modulation and potentiodynamic polarization indicated that this material has excellent inhibiting features in very low concentrations. The influence of DC trend on the explanation of electrochemical noise data was evaluated by polynomial fitting and the optimum polynomial order m=4 was obtained. Noise resistance and the inhibition efficiency was calculated and compared in different methods. The theory of shot noise in frequency domain was used to obtain the electrochemical event charge. The corroded surface of steel in the absence and existence of thiazole compound was studied by Atomic force microscopy. 

Abstract Lanthanide-doped gadolinium nanomaterials have attracted considerable attention due to their promising applications in biological imaging. Sodium gadolinium fluoride (β-NaGdF4) nanomaterials act as perfect host for doping of luminescent lanthanide ions. Due to heavy nature of gadolinium, it can strongly absorb X-ray radiations. Therefore, Gd-based nanomaterials are applied as contrast agents for X-ray tomography (CT). Presence of seven unpaired electrons in Gd+3 ion, its large magnetic moment and long electronic relaxation time makes it an ideal candidate to enhance water proton relaxation rates. These characteristics make Gd-based nanomaterial useful for their potential application as MRI contrast agents. In this work, sodium gadolinium fluoride is doped with ytterbiumand erbium to produce β-NaGdF4:Yb/Er as core nanocrystals. They are subsequently coated with sodium gadolinium fluoride doped with neodymium (β-NaGdF4:Nd) to produce β-NaGdF4:Yb/Er@β-NaGdF4:Nd core-shell nanocrystals. Powder X‐ray diffraction (XRD) results indicated that β-NaGdF4 (host), β-NaGdF4:Yb/Er (core) and β-NaGdF4:Yb/Er@β-NaGdF4:Nd (core-shell) nanocrystals all exist in hexagonal crystalline phase. While Dynamic Light Scattering (DLS) results indicated that the particle size of the synthesized nanocrystals was in range of 12 to 27 nm. FTIR results confirmed that the synthesized nanocrystals were stabilized by oleic acid. Nanocrystals reported in this work are expected to be useful trimodal contrast agents for photoluminescence, X-ray tomography and Magnetic Resonance Imaging (MRI).