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The first European settlements in the new world faced technical issues with the help of the XVI century scientific advances. Besides briefly exposing the scientific and technological situation, this paper explores, with the help of reverse engineering, two singular mechanical wits representative of the technological advances introduced in America to overcome different problems. Firstly, a pump, based on an alternative movement system through crankshafts and pistons used against the continuous flooding suffered in the Ciudad de México valley. Although flooding remained a problem (it was solved in the XX century), hydraulic pumps were essential for continuous soil drainage. Secondly, a port crane for handling cannons, military devices, and construction materials during the Lima fortification in the XVII century. For both cases, reverse engineering, through engineering methods, Computer-Aided Design CAD programs, and additive manufacturing, provides virtual and/or tangible mockups that help to analyze and improve our knowledge about the dimensions, materials, and functions of used (and currently lost) mechanical systems during the American colonization. [ABSTRACT FROM AUTHOR]

In this paper, we analyze a massive dataset with registers of the movement of vehicles in the bus rapid transit system Metrobús in Mexico City from February 2020 to April 2021. With these records and a division of the system into 214 geographical regions (segments), we characterize the vehicles' activity through the statistical analysis of speeds in each zone. We use the Kullback–Leibler distance to compare the movement of vehicles in each segment and its evolution. The results for the dynamics in different zones are represented as a network where nodes define segments of the system Metrobús and edges describe similarity in the activity of vehicles. Community detection algorithms in this network allow the identification of patterns considering different levels of similarity in the distribution of speeds providing a framework for unsupervised classification of the movement of vehicles. The methods developed in this research are general and can be implemented to describe the activity of different transportation systems with detailed records of the movement of users or vehicles. [ABSTRACT FROM AUTHOR]

Alegoría de la construcción and Alegoría del trabajo were the first mural paintings commissioned to Saturnino Herrán (1887–1918), and they occupied a significant place in one of the most important schools in Mexico. The non-invasive methodology employed included different documentation phases and in situ multi-technique analyses. Hyperspectral imaging and digital radiography were used for a general characterization of the materials and were complemented with localized analyses by portable microscopy, and XRF and FORS spectroscopies. A complete identification of the original and the restoration palettes was achieved. Results from this work allowed us to understand the production context, painting technique, and conservation state, thus providing insights for the proper conservation of these murals, while also unveiling a new perception of the artist and his historical place among the muralist movement. [ABSTRACT FROM AUTHOR]

Acute respiratory infections (ARIs) are a major cause of morbidity and mortality among children. The causative pathogens show geographic and seasonal variations. We retrospectively evaluated the frequency and seasonality of respiratory pathogens in children and adolescents (age: 0–19 years) with ARIs treated between January 1, 2021, and March 31, 2022, at a single center in Mexico. Out of 2400 patients, 1,603 were diagnosed with SARS-CoV-2 infection and 797 were diagnosed with other common respiratory pathogens (CRPs). Of the 797 patients, 632 were infected with one CRP and 165 with > 2 CRPs. Deaths occurred only in SARS-CoV-2-infected patients. Rhinovirus/Enterovirus, respiratory syncytial virus B, and parainfluenza virus 3 were the most prevalent in cases with single and multiple infections. CRP showed a high frequency between autumn and winter of 2021, with higher incidence of hospitalization compared to COVID-19. The main comorbidities were immunosuppression, cardiovascular disease (CD), and asthma. The frequency of CRPs showed a downward trend throughout the first half of 2021. CRPs increased in single- and co-infection cases between the fourth and fifth waves of COVID-19, probably due to decreased nonpharmaceutical interventions and changes in diagnostic tests. Age, cyanosis (symptom), and immunosuppression (comorbidity) were found to differentiate between SARS-CoV-2 infection and CRP infection. [ABSTRACT FROM AUTHOR]

The quality of the urban environment is crucial for societal well-being. Yet, measuring and tracking the quality of urban environment, their evolution, and spatial disparities is difficult due to the amount of on-the-ground data needed to capture these patterns. The growing availability of street view images presents new prospects in identifying urban features. However, the reliability and consistency of these methods across different locations and time remains largely unexplored. We aim to develop a comprehensive index of urban quality and change at the street segment level using Google Street View (GSV) imagery. We focus on eight object classes that indicate urban decay or contribute to an unsightly urban space, such as potholes, graffiti, garbage, tents, barred or broken windows, discolored or dilapidated façades, weeds, and utility markings. We train an object detection model on a dataset of images from different cities and assess the performance of these urban indices. We evaluate the effectiveness of this method in various urban contexts over time and discuss its potential for urban planning and public policy. We demonstrate the use of these indices in three applications: the Tenderloin in San Francisco, the Doctores and Historic Center neighborhoods in Mexico City, and South Bend, Indiana. [ABSTRACT FROM AUTHOR]

We report the major highlights of the School of Cheminformatics in Latin America, Mexico City, November 24–25, 2022. Six lectures, one workshop, and one roundtable with four editors were presented during an online public event with speakers from academia, big pharma, and public research institutions. One thousand one hundred eighty-one students and academics from seventy-nine countries registered for the meeting. As part of the meeting, advances in enumeration and visualization of chemical space, applications in natural product-based drug discovery, drug discovery for neglected diseases, toxicity prediction, and general guidelines for data analysis were discussed. Experts from ChEMBL presented a workshop on how to use the resources of this major compounds database used in cheminformatics. The school also included a round table with editors of cheminformatics journals. The full program of the meeting and the recordings of the sessions are publicly available at https://www.youtube.com/@SchoolChemInfLA/featured. [ABSTRACT FROM AUTHOR]

Following the 1923 Kanto earthquake in Japan, Japanese researchers noticed the strong effects of surface geology on seismic motion (ESG) and began to investigate these effects to quantify the site amplification factors (SAFs) associated with soft surface sediments. On the other side of the Pacific Ocean, ESG received limited attention until the 1985 Michoacan, Mexico earthquake revealed significant long-period amplification inside Mexico City that manifested as the source of devastating damage to high-rise buildings. Since then, seismologists and earthquake engineers have performed a lot of studies on various ESG issues worldwide. We have not yet reached common conclusions on how to quantitatively predict SAFs over a broad frequency band of engineering interest, 0.1 to 20 Hz, for moderate to strong input from different types of earthquakes in different tectonic settings. However, we found here several basic guidelines useful for successfully modeling ground motions as a common approach to ESG studies. First, in this letter, we briefly review our history of understanding ESG, which is closely related to the key settings required for reliable quantifications of SAFs, and then introduce various emerging techniques for broadband quantitative evaluations of SAFs based on the vast amount of observed ground motions primarily from dense Japanese strong-motion networks. Based on the findings of our investigation and the physical relationships behind the parameters, the authors would like to recommend that researchers on ESG and related topics would refer to the five basic guidelines proposed in the conclusions for the successful implementation of techniques to delineate SAFs in a specific region of interest, such as the use of Fourier spectra instead of response spectra. We have started applying the proposed techniques to regions outside Japan. The implementation of the statistical validation exercises will follow. [ABSTRACT FROM AUTHOR]

Previous empirical studies on the correlation between residential burglary and concentrated disadvantage (CD) in Latin America commonly omit the spatial elements of the relationship. Using Mexico City (CDMX) residential burglary data for the period 2016 to 2018, we examine the predictive capacity of concentrated disadvantage in relation to residential burglary patterns, using a Geographically Weighted Regression approach to check whether their correlation varies across CDMX police quadrants. Controlling for relevant structural variables associated with residential burglary in previous studies, we find that the relationship between CD and residential burglary is positive in 844 out of 846 police quadrants (99.7%) and significantly much steeper in some quadrants than others –up to four times the median local slope. Thus, one key implication is that as this relationship is affected by spatial heterogeneity, traditional regression-to-the-mean analyses may misinform evidence-based crime prevention policies. [ABSTRACT FROM AUTHOR]

This article seeks to explain the multiplication of social environmental conflicts in Mexico as a consequence of expanding and intensifying extractive activities. It examines how the Mexican state has provided private and foreign capital greater access to the country's natural resources in the transition from state-led import-substituting industrialization to export-oriented market-led development. This, it argues, has led to accelerating material extraction rates in the context of rising global demand for primary commodities; while the negative environmental and social impacts have in turn led to a growing number of conflicts involving the inhabitants of directly affected rural communities, who organize to resist. Based on standardized procedures for material flow analysis, it presents the results of an investigation into the domestic extraction rates of minerals, metal ores, biomass, and fossil fuels from Mexico, between 1990 and 2018. It finds that domestic extraction rates increased significantly during this period, with the exception of fossil fuels, which peaked in 2006, declining thereafter due to the exhaustion of the country's most important oil reserves. The evolution of domestic extraction rates is juxtaposed with the emergence of related social environmental conflicts by drawing on multiple databases of conflicts around extractive activities in Mexico. [ABSTRACT FROM AUTHOR]

We report the main conclusions of the first Chemoinformatics and Artificial Intelligence Colloquium, Mexico City, June 15–17, 2022. Fifteen lectures were presented during a virtual public event with speakers from industry, academia, and non-for-profit organizations. Twelve hundred and ninety students and academics from more than 60 countries. During the meeting, applications, challenges, and opportunities in drug discovery, de novo drug design, ADME-Tox (absorption, distribution, metabolism, excretion and toxicity) property predictions, organic chemistry, peptides, and antibiotic resistance were discussed. The program along with the recordings of all sessions are freely available at https://www.difacquim.com/english/events/2022-colloquium/. [ABSTRACT FROM AUTHOR]

The results of a study of the elemental concentrations in PM10 samples collected at a site in southwest Mexico City during 2016 and 2019, are presented. The concentrations of up to 19 elements were measured with X-ray fluorescence (XRF). These analyses were complemented with ion chromatography for eight ionic species (for the samples collected in 2016). The behaviors of the gravimetric mass and elemental concentrations are described for the morning, afternoon, and night-time periods in 2019. The elemental concentrations observed in the PM10 samples did not present significant changes as compared to those published in previous works. It was found that the gravimetric mass concentrations were always below the official standards, except during a contingency period in May 2019. The positive matrix factorization (PMF) receptor model was used to identify contaminating sources and their relative contributions to the concentrations of the detected elements. The soil-related factors were the most abundant contributors, with other components associated to traffic, biomass burning, fuel oil, secondary aerosol, and dust resuspension. The occurrence of episodes in 2019 is explained with the aid of PMF and back-trajectories, while the contingency period is due to other chemical species not detected in PM10 with XRF. A comparison with data collected in 2005 in downtown Mexico City is also carried out, as well as with urban areas in other countries. [ABSTRACT FROM AUTHOR]

Cocaine use disorder (CUD) is a substance use disorder (SUD) characterized by compulsion to seek, use and abuse of cocaine, with severe health and economic consequences for the patients, their families and society. Due to the lack of successful treatments and high relapse rate, more research is needed to understand this and other SUD. Here, we present the SUDMEX CONN dataset, a Mexican open dataset of 74 CUD patients (9 female) and matched 64 healthy controls (6 female) that includes demographic, cognitive, clinical, and magnetic resonance imaging (MRI) data. MRI data includes: 1) structural (T1-weighted), 2) multishell high-angular resolution diffusion-weighted (DWI-HARDI) and 3) functional (resting state fMRI) sequences. The repository contains unprocessed MRI data available in brain imaging data structure (BIDS) format with corresponding metadata available at the OpenNeuro data sharing platform. Researchers can pursue brain variability between these groups or use a single group for a larger population sample. Measurement(s) functional brain measurement • Diffusion Weighted Imaging • Abnormality of brain morphology • Alteration Of Cognitive Function • Clinical Study Technology Type(s) Functional Magnetic Resonance Imaging • Diffusion Weighted Imaging • Turbo Field Echo MRI • neuropsychological test • Clinical Evaluation Factor Type(s) Cocaine Dependence Sample Characteristic - Organism Homo Sample Characteristic - Location Mexico City [ABSTRACT FROM AUTHOR]

Corruption has a significant impact on economic growth, democracy, and inequality. It has sever consequences at the human level. Public procurement, where public resources are used to purchase goods or services from the private sector, are particularly susceptible to corrupt practices. However, government turnover may bring significant changes in the way public contracting is done, and thus, in the levels and types of corruption involved in public procurement. In this respect, México lived a historical government transition in 2018, with the new government promising a crackdown on corruption. In this work, we analyze data from more than 1.5 million contracts corresponding from 2013 to 2020, to study to what extent this change of government affected the characteristics of public contracting, and we try to determine whether these changes affect how corruption takes place. To do this, we propose a statistical framework to compare the characteristics of the contracting practices within each administration, separating the contracts in different classes depending on whether or not they were made with companies that have now been identified as being involved in corrupt practices. We find that while the amount of resources spent with companies that turned out to be corrupt has decreased substantially, many of the patterns followed to contract these companies were maintained, and some of those in which changes did occur, are suggestive of a larger risk of corruption. [ABSTRACT FROM AUTHOR]

Nopal (Opuntia ficus-indica) is widely cultivated in Mexico as a food raw material. However, the environmental impact caused by the growth and harvesting life cycle of this feedstock has been poorly studied. In this study, the environmental consequences of the growing, harvesting and transportation processes of nopal were evaluated with the aid of a life cycle assessment (LCA) method using SimaPro software version 8.5.2. The results showed that global warming (83.13%) and ozone depletion (99.25%) were significantly affected by the cultivation process due to current fertilization methods. The number of estimated gasses and chemicals emitted like ammonium (18.88 kgNH3/ha/year), nitrogen oxides (35.32 kgNOX–NO2/ha/year) and nitrous oxide (28.57 kgN2O/ha/year) were believed to be the result of the chemical fertilizers employed. The current cultivation process additionally reported emissions of nitrate (886.48 kgNO3/ha/year) and phosphorus (0.041 kg P/ha/year) caused by soil water erosion. The transportation process reported low levels of environmental impact; however, a significant amount of acidification (88.54%), mineral depletion (80.95%) and water consumption (84.06%) resulted from the process utilized to produce nopal in brine. In summary, the entire process resulted in a Global Warming Potential (GWP) of 0.562 kg/CO2 eq. [ABSTRACT FROM AUTHOR]

Background/objective: Changes in metabolism and extensive hemodynamic adjustments occur during normal pregnancy. The presence of maternal obesity imposes an overload to these physiological adaptations that may result in increased risk for the development of cardiometabolic complications during and after pregnancy. The aim of this study is to describe total cholesterol (TC), triglycerides (TG), glucose, and arterial blood pressure (BP) trajectories and to analyze the association of these cardiometabolic risk indicators during pregnancy with pre-pregnancy body mass index (pBMI) and monthly gestational weight gain (MGWG). Subjects/methods: A prospective cohort study of pregnant women was conducted in Mexico City. Monthly samples of blood were taken during clinical follow-up and biochemical and blood pressure were measured during each visit. Adjusted linear mixed-effect regression models were fit to describe the trajectories of these biomarkers during pregnancy and to analyze the association with pBMI and MGWG. Results: Seven hundred and twenty women were included of which 16.6% had pre-gestational obesity, 33.2% had pre-gestational overweight, 45.8% had normal pBMI and 4.4% had pre-gestational underweight. Women with pre-gestational obesity had higher lipids concentrations in the beginning of pregnancy (TC: β ̂ = 33.08, p = 0.010; TG: β ̂ = 31.29, p = <0.001) but the concentrations increased less than in women with normal pBMI (TC: β ̂ = −14.18, p = 0.001; TG: β ̂ = −5.42, p < 0.001). By the end of pregnancy, women with pre-gestational obesity had lower concentrations of lipids than women with normal pBMI. By contrast, women with pre-gestational obesity had higher glucose concentrations and higher BP levels than women with normal pBMI over pregnancy. Conclusions: pBMI is differentially associated with longitudinal trajectories of maternal biochemical markers of cardiometabolic risk. MGWG did not significantly affect the biochemical indicators or BP trajectories. Our results suggest that pBMI is more relevant to predicting adverse cardiometabolic markers trajectories during pregnancy than MGWG. [ABSTRACT FROM AUTHOR]

More than 7 thousand wildfires were recorded over Mexico in 2019, affecting almost 640 thousand hectares. Most of these fires occurred during the spring season generating dense smoke plumes, impacting urban areas in the central part of the Mexican plateau. From May 10 to 17, 2019, biomass burning (BB) plumes affected Mexico City (MC) and diffused across the basin, producing PM2.5 levels ~ 2 times higher than the nation's air quality standards. Average PM2.5 concentrations increased sharply from 29.4 ± 7.2 µg m−3 to 65.1 ± 13.6 µg m−3 when the dense smoke plumes were detected. The higher particle concentration impacted the aerosol optical depth (AOD) as values ~ 3 times greater than the annual mean (0.32 ± 0.12) were measured, which resulted in a 17% loss of global horizontal irradiation (GHI). Under these severe pollution conditions, the visibility (Va) was reduced by ~ 80%. The high incidence of strong absorbent particles, such as soot and tarballs was revealed through electron microscopy and X-ray fluorescence (XRF) analysis. These techniques show chemical similarities between MC aerosols and those from the high-altitude (~ 4010 m. a. g. l.) Altzomoni Atmospheric Observatory, evidencing a strong influence of the BB emissions, suggesting a regional transport of these pollutants. [ABSTRACT FROM AUTHOR]

Urban wastewater is a resource that can be reused, but its management must be carefully executed, considering its potential impact on public and environmental health. Unfortunately, marked differences in the quality of treatment, management, collection, and the monitoring of wastewater exist among low-, middle-, and high-income countries. This is the case of the Mezquital Valley, a semi-rural area that is composed of agricultural and industrial communities on the outskirts of Mexico City. For over 100 years, wastewater from Mexico City and its areas of conurbation has been sent to the Mezquital Valley, with few studies having been conducted to assess the existence and severity of bacterial and pathogen infiltration into the local aquifer. In this research, we present an assessment of wastewater infiltration transported from Mexico City, used for irrigation, with potential infiltration into the Mezquital Valley aquifer. We utilized stable isotope analysis of deuterium and oxygen-18 to determine whether a mixture of untreated wastewater from the Mexico City Metropolitan Area (MCMA) flows into the Mezquital aquifer. Also, tests for adenovirus, rotavirus, fecal coliform, fecal enterococci, Giardia lamblia, and Cryptosporidium parvum were employed to determine the presence of fecal indicators and pathogens in different water sources in the study area. The results show the presence of indicators and pathogens in local wells used as water supply in Mezquital Valley. The presence of such indicators suggests that pathogens can reach the water consumed by the inhabitants, posing a hazard to persons exposed to these waters during their normal daily-life activities. [ABSTRACT FROM AUTHOR]

Lower tropospheric thermal structure greatly affects atmospheric boundary-layer (ABL) stability and mixing processes with the free troposphere. In particular, in polluted urban zones, ABL stratification becomes a key variable in air quality research. This study focuses on generating a climatology (1990–2017) of the seasonal variability of ABL thermal structure in Mexico City by way of radiosonde analysis. Thermal inversion intensity and frequency are shown to be greater during winter and spring, a behaviour which coincides with greater pollutant concentrations. Higher concentrations are found during the dry season (November to May) than during the rainy months. In addition, significantly higher than normal surface pollutant concentrations are found on days with simple thermal inversion layers as well as during multilayer inversion days. Furthermore, stable layers, determined by potential temperature, are found throughout the year but more frequently during winter, whereas stable layers based on the virtual potential temperature prevail all year. In regions of complex terrain, such multiple stable layers have also been identified by previous authors. Additionally, the most unstable surface layers (in which the bulk Richardson number ( Ri B ) is small) develop during the rainy season, whereas during winter there are more levels in the vertical column with higher Ri B values. Although the Mexico City ABL and pollution episodes have been widely studied, this represents the first long-term investigation to consider the thermal stability of the ABL. Therefore, the present study provides a baseline for further research employing different observational techniques and high-resolution numerical models. [ABSTRACT FROM AUTHOR]