Relationship Between DDT Concentrations with Multiparity and Breastfeeding History.

Organochlorine pesticides are persistent organic pollutants (POPs) that can enter the body through environmental exposure and food consumption. The aim of this study was to investigate the influence of parity and breast milk consumption on dichlorodiphenyltrichloroethane (DDT) concentrations in women from Southern Mexico. Gas chromatography was used to detect o,p'-DDT, p,p'-DDT, and p,p'-dichlorodiphenyldichloroethylene (DDE) in milk samples. The frequency of detection of the compounds was above 78%, finding low median concentrations of o,p'-DDT (0.010 mg/kg) and p,p'-DDT (0.043 mg/kg) compared to p,p'-DDE (0.672 mg/kg). The median DDE/DDT ratio was 14.7. The concentrations of o,p'-DDT and p,p'-DDE were significantly higher in primiparous women (0.010 mg/kg and 0.868 mg/kg) compared to multiparous women (0.005 mg/kg and 0.583 mg/kg) (p < 0.05). Breastfed donors had similar levels of o,p'-DDT, p,p'-DDE, and Σ-DDT compared to those who were not breastfed.

Risk Factors Associated with COVID-19 Lethality: A Machine Learning Approach Using Mexico Database.

Identifying risk factors associated with COVID-19 lethality is crucial in combating the ongoing pandemic. In this study, we developed lethality predictive models for each epidemiological wave and for the overall dataset using the Extreme Gradient Boosting technique and analyzed them using Shapley values to determine the contribution levels of various features, including demographics, comorbidities, medical units, and recent medical information from confirmed COVID-19 cases in Mexico between February 23, 2020, and April 15, 2022. The results showed that pneumonia and advanced age were the most important factors predicting patient death in all cohorts. Additionally, the medical unit where the patient received care acted as a risk or protective factor. IMSS medical units were identified as high-risk factors in all cohorts, except in wave four, while SSA medical units generally were moderate protective factors. We also found that intubation was a high-risk factor in the first epidemiological wave and a moderate-risk factor in the following waves. Female gender was a protective factor of moderate-high importance in all cohorts, while being between 18 and 29 years old was a moderate protective factor and being between 50 and 59 years old was a moderate risk factor. Additionally, diabetes (all cohorts), obesity (third wave), and hypertension (fourth wave) were identified as moderate risk factors. Finally, residing in municipalities with the lowest Human Development Index level represented a moderate risk factor. In conclusion, this study identified several significant risk factors associated with COVID-19 lethality in Mexico, which could aid policymakers in developing targeted interventions to reduce mortality rates.

Feature Extraction of a Non-Stationary Seismic-Acoustic Signal Using a High-Resolution Dyadic Spectrogram.

Using a novel mathematical tool called the Te-gram, researchers analyzed the energy distribution of frequency components in the scale-frequency plane. Through this analysis, a frequency band of approximately 12 Hz is identified, which can be isolated without distorting its constituent frequencies. This band, along with others, remained inseparable through conventional time-frequency analysis methods. The Te-gram successfully addresses this knowledge gap, providing multi-sensitivity in the frequency domain and effectively attenuating cross-term energy. The Daubechies 45 wavelet function was employed due to its exceptional 150 dB attenuation in the rejection band. The validation process encompassed three stages: pre-, during-, and post-seismic activity. The utilized signal corresponds to the 19 September 2017 earthquake, occurring between the states of Morelos and Puebla, Mexico. The results showcased the impressive ability of the Te-gram to surpass expectations in terms of sensitivity and energy distribution within the frequency domain. The Te-gram outperformed the procedures documented in the existing literature. On the other hand, the results show a frequency band between 0.7 Hz and 1.75 Hz, which is named the planet Earth noise.

Evaluation of tools for taxonomic classification of viruses.

Viruses are the most abundant infectious agents on earth, and they infect living organisms such as bacteria, plants and animals, among others. They play an important role in the balance of different ecosystems by modulating microbial populations. In humans, they are responsible for some common diseases and may cause severe illnesses. Viral metagenomic studies have become essential and offer the possibility to understand and extend the knowledge of virus diversity and functionality. For these approaches, an essential step is the classification of viral sequences. In this work, 11 taxonomic classification tools were compared by analysing their performances, in terms of sensitivity and precision, to classify reads at the species and family levels using the same (viral and nonviral) datasets and evaluation metrics, as well as their processing times and memory requirements. The results showed that factors such as richness (numbers of viral species in samples), taxonomic level in the classification and read length influence tool performance. High values of viral richness in samples decreased the performances of most tools. Additionally, the classifications were better at higher taxonomic levels, such as families, compared to lower taxonomic levels, such as species, and were more evident in short reads. The results also indicated that BLAST and Kraken2 were the best tools for classifying all types of reads, while FastViromeExplorer and VirusFinder were only good when used for long reads and Centrifuge, DIAMOND, and One Codex when used for short reads. Regarding nonviral datasets (human and bacterial), all tools correctly classified them as nonviral.

Socioeconomic determinants of health and COVID-19 in Mexico.

INTRODUCTION: The population living in conditions of poorness has a heavier pathological burden than social strata with better economic possibilities. OBJECTIVE: To determine the influence of socioeconomic and demographic factors on COVID-19 morbidity, mortality and lethality in municipalities and states of Mexico. METHODS: Morbidity, mortality and lethality associated with COVID-19 were analyzed according to the human development index and its indicators, and type of population. Descriptive statistical analyses, correlations between developmental variables and morbidity, mortality and lethality, association tests and hierarchical groupings were carried out. RESULTS: Positive correlations were observed between morbidity and mortality and the human development index; COVID-19 fatality increased as the values of said index decreased. There was a significantly higher risk of elevated mortality in localities with moderate and low development, and in those with less than 49,999 inhabitants. The main factors associated with fatality were lack of access to health services, income vulnerability and social deprivation. CONCLUSIONS: The evidence generated should lead to decisions aimed at improving the quality of life of the population with social deprivations and vulnerabilities, which needs to be protected against the consequences of current COVID-19 pandemic.

INTRODUCCIÓN: La población en situación de pobreza presenta una carga patológica mayor que los estratos sociales con mejores posibilidades económicas. OBJETIVO: Determinar la influencia de los factores socioeconómicos y demográficos en la morbilidad, mortalidad y letalidad de COVID-19 en municipios y estados de México. MÉTODOS: Se analizó la morbilidad, mortalidad y letalidad asociadas a COVID-19 conforme el índice de desarrollo humano y sus indicadores, así como el tipo de población. Se realizaron análisis estadísticos descriptivos, de correlación entre variables de desarrollo versus morbilidad, mortalidad y letalidad, pruebas de asociación y agrupaciones jerárquicas. RESULTADOS: Se observaron correlaciones positivas entre la morbilidad y mortalidad y el índice de desarrollo humano; la letalidad por COVID-19 aumentó conforme disminuyó dicho índice. Existió riesgo significativamente superior de alta letalidad en las localidades con moderado y bajo desarrollo, así como en aquellas con menos de 49 999 habitantes. Los principales factores asociados a la letalidad fueron la falta de acceso a los servicios de salud, la vulnerabilidad por ingreso y la carencia social. CONCLUSIONES: La evidencia generada debe llevar a decisiones tendentes al mejoramiento de la calidad de vida de la población con carencias y vulnerabilidades sociales, que necesita ser protegida contra las consecuencias de la actual pandemia de COVID-19.

Determinantes socioeconómicos de salud y COVID-19 en México / Socioeconomic determinants of health and COVID-19 in Mexico

Resumen Introducción: La población en situación de pobreza presenta una carga patológica mayor que los estratos sociales con mejores posibilidades económicas. Objetivo: Determinar la influencia de los factores socioeconómicos y demográficos en la morbilidad, mortalidad y letalidad de COVID-19 en municipios y estados de México. Métodos: Se analizó la morbilidad, mortalidad y letalidad asociadas a COVID-19 conforme el índice de desarrollo humano y sus indicadores, así como el tipo de población. Se realizaron análisis estadísticos descriptivos, de correlación entre variables de desarrollo versus morbilidad, mortalidad y letalidad, pruebas de asociación y agrupaciones jerárquicas. Resultados: Se observaron correlaciones positivas entre la morbilidad y mortalidad y el índice de desarrollo humano; la letalidad por COVID-19 aumentó conforme disminuyó dicho índice. Existió riesgo significativamente superior de alta letalidad en las localidades con moderado y bajo desarrollo, así como en aquellas con menos de 49 999 habitantes. Los principales factores asociados a la letalidad fueron la falta de acceso a los servicios de salud, la vulnerabilidad por ingreso y la carencia social. Conclusiones: La evidencia generada debe llevar a decisiones tendentes al mejoramiento de la calidad de vida de la población con carencias y vulnerabilidades sociales, que necesita ser protegida contra las consecuencias de la actual pandemia de COVID-19.

Abstract Introduction: The population living in conditions of poorness has a heavier pathological burden than social strata with better economic possibilities. Objective: To determine the influence of socioeconomic and demographic factors on COVID-19 morbidity, mortality and lethality in municipalities and states of Mexico. Methods: Morbidity, mortality and lethality associated with COVID-19 were analyzed according to the human development index and its indicators, and type of population. Descriptive statistical analyses, correlations between developmental variables and morbidity, mortality and lethality, association tests and hierarchical groupings were conducted. Results: Positive correlations were observed between morbidity and mortality and the human development index; COVID-19 fatality increased as the values of said index decreased. There was a significantly higher risk of elevated mortality in localities with moderate and low development, and in those with less than 49,999 inhabitants. The main factors associated with fatality were lack of access to health services, income vulnerability and social deprivation. Conclusions: The evidence generated should lead to decisions aimed at improving the quality of life of the population with social deprivations and vulnerabilities, which needs to be protected against the consequences of current COVID-19 pandemic.

Covid-19 y el índice de desarrollo humano en México.

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A statistically coherent robust multidimensional classification scheme for water.

Serious limitations of the existing water classification schemes prompted us to propose a new statistically coherent water nomenclature system. An extensive database of ionic charge-balanced concentrations of 8 elements (4 cations Ca, Mg, Na, and K; and 4 anions SO4, Cl, HCO3, and CO3), in 46,292 multivariate outlier-free simulated samples, was used for training the multidimensional classification system. The initial assignment for 16 classes was achieved from the greater molar concentration concept of each cation and anion, called the Greater molar conc model. Seven hybrid log-ratios (hlr) from 8 elemental concentrations were used for linear discriminant analysis (LDA) and canonical analysis to propose 16 multidimensional discriminant functions from the 7 hlr model. The LDA and canonical analysis were also performed on the initial molar concentrations of 7 elements, without any log-transformation, which was designated as the 7 M conc model. The robustness of these three classification systems (7 hlr, 7 M conc, and Greater molar conc) was tested against analytical uncertainty propagation and mineral-water interaction effects. The 7 hlr model, due to its higher robustness, was considered as the best option for the nomenclature of the 16 types of water. From the probability concept, it was possible to identify hybrid water types, along with the basic or primary types of water. Our water classification scheme (7 hlr model under the "basic+hybrid" option) can classify as many as 256 different classes of water. Due to the clearly high complexity of the proposed classification scheme, we developed a new online computer program WaterMClaSys_LDA (Water Molar Classification System from Linear Discriminant Analysis) available at our web portal http://tlaloc.ier.unam.mx, for use by anyone after registration and log-in. The usefulness of the new classification scheme is illustrated by applications to groundwater, lake water, and geothermal water samples from South India, Mongolia, and western Turkey, respectively.

Uso de bleomicina en el manejo del derrame pleural recidivante maligno / Bleomycin in the management of malignant recurrent pleural effusion

Introducción: El derrame pleural recidivante maligno se reproduce en breve tiempo y requiere el diagnóstico etiológico positivo de malignidad, la etiología más frecuente es el cáncer de pulmón. La pleurodesis química es el tratamiento de elección con la aplicación intrapleural de sustancias sinfisiantes. Objetivo: Describir la respuesta clínica y radiológica de los enfermos con derrame pleural recidivante maligno con el uso de bleomicina. Método: Estudio observacional comparativo en 30 pacientes con derrame pleural recidivante maligno divididos en dos grupos, en uno se aplicó la bleomicina intrapleural y al otro yodo povidona. Resultado: El 33,3 por ciento fueron del sexo masculino, 60 por ciento perteneció al grupo de edades de 60-69 años. El grupo tratado con bleomicina presentó una respuesta clínica favorable en los síntomas, p<0,005 después de la pleurodesis. En la evaluación de la respuesta radiológica, 66,6 por ciento pacientes tratados con la bleomicina tuvieron una resolución completa. Conclusiones: Se logró una buena respuesta clínica-radiológica con la pleurodesis química similar entre ambas modalidades de tratamiento. Se obtuvieron mejores resultados y menos reacciones adversas con la bleomicina intrapleural(AU)

Introduction: The malignant recurrent pleural effusion reproduces in short time and it requires a positive etiological diagnosis of malignancy, the most frequent etiology is lung cancer. Chemical pleurodesis is the treatment of choice with the intrapleural application of symphysiating substances. Objective: To describe the clinical and radiological response of patients with malignant recurrent pleural effusion with the use of bleomycin. Method: A comparative observational study in 30 patients with recurrent malignant pleural effusion was carried out. They were divided into two groups, one used intrapleural bleomycin and the other group used povidone iodine. Result: 33.3 percent were male, 60 percent belonged to the 60-69 age group. The group treated with bleomycin presented favorable clinical response in symptoms, p <0.005 after pleurodesis. At the evaluation of the radiological response, 66.6 percent patients treated with bleomycin had a complete resolution. Conclusions: Good clinical-radiological response was achieved with similar chemical pleurodesis between both treatment modalities. Better results and fewer adverse reactions were obtained with intrapleural bleomycin(AU)

Dietary habits associated with the presence of organochlorine pesticides in human milk.

This study aims to establish the relationship between the consumption of certain foods and the presence of organochlorine pesticides in human milk. A total of 167 samples of breastmilk were collected. Sample analysis was carried out by gas chromatography with electron capture detector. Pesticide concentrations (op'DDT, pp'DDT, pp'DDE, Σ-DDT, HCB, ß-HCH) were grouped by consumption level of fish, dairy products, meat, eggs, and seafood and then were compared to each other. The odds ratio (OR) was calculated between the concentration of pesticides (higher and/or lower than median) and the exposure variable (high consumption). The results indicated low median concentrations of HCB, ß - HCH, op'DDT and pp'DDT, whose fluctuations and trends between different frequencies of food consumption were not significant. pp'DDE and Σ - DDT values according to the increase in consumption of fish were significantly increased. Women with high fish consumption have a higher risk of high concentrations of pp'DDE and Σ-DDT (OR: high consumption: 5.6 (1.3-23.6). A protective effect was observed in the consumption of dairy products (ß-HCH and op'DDT), meat (HCB), and seafood (pp'DDT). These results suggest that it is possible that the consumption of fish, dairy products, meat, and seafood influences the presence of organochlorine pesticides in the studied population.

Comparative performance of four single extreme outlier discordancy tests from Monte Carlo simulations.

Using highly precise and accurate Monte Carlo simulations of 20,000,000 replications and 102 independent simulation experiments with extremely low simulation errors and total uncertainties, we evaluated the performance of four single outlier discordancy tests (Grubbs test N2, Dixon test N8, skewness test N14, and kurtosis test N15) for normal samples of sizes 5 to 20. Statistical contaminations of a single observation resulting from parameters called δ from ±0.1 up to ±20 for modeling the slippage of central tendency or ε from ±1.1 up to ±200 for slippage of dispersion, as well as no contamination (δ = 0 and ε = ±1), were simulated. Because of the use of precise and accurate random and normally distributed simulated data, very large replications, and a large number of independent experiments, this paper presents a novel approach for precise and accurate estimations of power functions of four popular discordancy tests and, therefore, should not be considered as a simple simulation exercise unrelated to probability and statistics. From both criteria of the Power of Test proposed by Hayes and Kinsella and the Test Performance Criterion of Barnett and Lewis, Dixon test N8 performs less well than the other three tests. The overall performance of these four tests could be summarized as N2≅N15 > N14 > N8.