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The National Soil Strategy for Sustainable Agriculture (ENASAS) arises in response to the increasing need to organize, coordinate and strengthen the implementation of actions oriented to the sustainable management of Mexico's agricultural soils. The measures recommended in this paper allow the conservation and maintenance of soils' essential functions for agriculture, food security and population well‐being. The health and quality of agricultural soils are under constant pressure from several factors, mainly anthropogenic. One of ENASAS's objectives is to identify and stop the causes involved in land degradation processes using a systemic approach. From this perspective, the participation of various actors in sustainable soil management allows the integration of different systems, practices, techniques and knowledge that promotes awareness among the entire population about the importance of soil resources. On the other hand, given current limitations on the availability of information necessary to support decision‐making and evaluate the result of the actions implemented, ENASAS promotes the generation of tools that provide reliable and updated data regarding Mexico's agricultural soils. In the same sense, this strategy encourages the development of scientific and technological research and the transfer of knowledge that meets the needs of farmers, particularly those who carry out their activities on a smaller scale. This perspective describes ENASAS as a multi‐institutional initiative that will support sustainable soil management practices across the country's agricultural systems of Mexico and contribute to the adaptation and mitigation of global environmental change. [ABSTRACT FROM AUTHOR]

The geological map of the Tres Vírgenes Volcanic Complex (TVVC) Baja California Sur, México consists of three northeast-southwest aligned stratovolcanoes named from older to younger, El Viejo, El Azufre, and La Virgen. The map (scale 1:20,000) comprises an area of 856 km2 edited on an ArcMap data set. The map compiles previous studies combined with new mapping and stratigraphy supported by 5 new 230Th/U geochronology in zircons. The TVVC sits on top of Cretaceous granite, Cenozoic volcaniclastics, the Esperanza basalt (7.64 Ma), and the Aguajito ignimbrite (1.17 Ma). The TVVC commenced its activity around 300 ka by constructing El Viejo volcano, followed by El Azufre volcano (∼173–128 ka), la Virgen scoria cones (∼128–112 ka), and La Virgen stratovolcano (∼112–22 ka). The La Virgen volcano emplaced the La Virgen rhyolitic tephra (∼31 ka), and the Upper Andesite lavas (∼22 ka). [ABSTRACT FROM AUTHOR]

The genetic study of animal populations has become a valuable tool in conservation programs, particularly of those species that are endangered. Different population parameters can be determined in both captive and wild animals to assess their genetic status and long-term viability. In Mexico, different genetic tools have been used in the three species of nonhuman primates to assess, reinforce or test different biological aspects that have been determined by observations and field work. Among others, taxonomic and biogeographic aspects, differentiation and population structures, patterns of kinship and social systems have been made to know and understand the biology of the species and direct conservation and survival strategies of the genus Alouatta in Mexico. [ABSTRACT FROM AUTHOR]

Air-quality monitoring and analysis are initial parts of a comprehensive strategy to prevent air pollution in cities. In such a context, statistical tools play an important role in determining the time-series trends, locating areas with high pollutant concentrations, and building predictive models. In this work, we analyzed the spatio-temporal behavior of the pollutant PM10 in the Monterrey Metropolitan Area (MMA), Mexico during the period 2010–2018 by applying statistical analysis to the time series of seven environmental stations. First, we used experimental variograms and scientific visualization to determine the general trends and variability in time. Then, fractal exponents (the Hurst rescaled range and Higuchi algorithm) were used to analyze the long-term dependence of the time series and characterize the study area by correlating that dependence with the geographical parameters of each environmental station. The results suggest a linear decrease in PM10 concentration, which showed an annual cyclicity. The autumn-winter period was the most polluted and the spring-summer period was the least. Furthermore, it was found that the highest average concentrations are located in the western and high-altitude zones of the MMA, and that average concentration is related in a quadratic way to the Hurst and Higuchi exponents, which in turn are related to some geographic parameters. Therefore, in addition to the results for the MMA, the present paper shows three practical statistical methods for analyzing the spatio-temporal behavior of air quality. [ABSTRACT FROM AUTHOR]

The article discusses the relationship between poverty, medicine resistance, diagnostics, HIV-AIDS, and their impact on tuberculosis in Mexico. Tuberculosis is one of the most infectious diseases in the world today, behind malaria and HIV-AIDS. Because of this, public health organizations devote much of their effort to its prevention and containment. This article focuses on several factors that have influenced the rise of tuberculosis in modern times, including drug resistance, poverty, and the disease's relationship to other autoimmune diseases.

Based on a detailed geological map and stratigraphy aided by new 230 Th/ 238 U and 206 P/ 238 U age determinations we established the eruptive chronology of the Tres Vírgenes Volcanic Complex (TVVC). The complex consists of three northeast-southwest aligned stratovolcanoes, which from older to younger are El Viejo, El Azufre, and La Virgen and associated cinder cones and domes. The alignment was fed from fissures that mark the southern trace of the left-lateral Cimarron Fault. The TVVC was built upon the basement rocks of the Peninsular Ranges Batholith (~99 Ma), the Santa Lucia Formation (21.6 Ma), the Esperanza basalt (7.6 Ma), and the 1.1 Ma ignimbrite of El Aguajito caldera. The TVVC began its formation at ca. 300 ka mainly with dacitic lava flows and domes that formed El Viejo volcano (4.2 km 3 ). At around 173 ka, activity migrated to the southwest to build El Azufre volcano (3.8 km 3 ) with the emission of dacitic lavas and several phases of dome construction and destruction with the generation of pyroclastic density currents. El Azufre's activity ended ~128 ka with the extrusion of the summit dome. At about 112 ka, volcanism migrated 4.2 km to the southwest to begin the construction of La Virgen Volcano through the emission of andesitic and dacitic lavas that built the largest cone of the complex until ~22 ka (31.2 km 3 ). This volcano was built upon several stages of cone construction with the emission of lava flows and peripheral dacitic domes and cinder cones. Between 128 and 112 ka six cinder cones vented along the Cimarron Fault between the La Virgen and El Azufre volcanoes. By assuming a constant emission of magma the total volume of the TVVC (39 km 3 ) was erupted at an average rate of 0.13 km 3 /kyr. Of this volume, effusive eruptions dominated the evolution of the complex (89%) of which 62% are dacites and 38% andesites. The TVVC rocks have compositions of 50–67 wt% in silica, and low-medium K (0.5–2.5 wt% K 2 O). Trace element signatures of the TVVC rocks (Sr/Y <40, La/Yb <10, Nb-Ti negative anomalies and relative enrichments of LILE and LREE) suggest a post-subduction mixture between adakitic and calc-alkaline magmas. Xenoliths of granodiorites hosted in lavas and La Virgen tephra suggest that magma chambers feeding the complex have stagnated at depths >2 km within the Peninsular Ranges Batholith as confirmed by geobarometry, aeromagnetic data, and the drill-holes of the geothermal field. Today, the Tres Vírgenes geothermal field generates 10 MW of electricity although future exploration of several nearby areas may increase such capacity. [ABSTRACT FROM AUTHOR]

Nucleic acid-amplification testing (NAT) is not routinely practiced in blood banks from most low-income countries. We did an exploratory comparison of the performance of the standard immunoassay-based screening tests for the hepatitis B (HBV) and C (HCV) viruses with that of NAT, in blood donors. From January 1999 to March 2005, 94,806 blood donors were screened for anti-HCV antibodies and for hepatitis B surface antigen (HBsAg). Also, an exploratory period of molecular screening was carried out on 100 consecutive blood donors to detect HBV DNA and HCV RNA by home-made PCR techniques without sera pooling. In the 75-month period of serologic screening, HBsAg was detected in 219 donors (0.23%; 95% CI, 0.20- 0.26%) and anti-HCV antibodies in 922 (0.97%; 95% CI, 0.90-1.03%). The annual trend for HBsAg prevalence had a decreasing pattern over the years (p<0.001), whereas that for anti-HCV did not (p=0.19). In the molecular screening cohort, HBV DNA was detected in one donor (1%; 95% CI, 0-6%) and HCV RNA in another (1%; 95% CI, 0-6%). All these 100 donors tested negative to HBsAg and anti-HCV. Thus, the prevalence of positive results for HBV and HCV did not differ if considering immunoassays or NAT; nevertheless, these methods did not coincide in detecting HBV or HCV in the molecular screening cohort. In conclusion, NAT can detect cases of HBV and HCV infections that standard immunoassay techniques can not, even in a highly selected population at low risk, like blood donors. Large-scale studies are warranted for NAT to be considered as a systematic method for screening of HBV and HCV in Mexican blood banks.