To predict the compressive strength of self compacting concrete with recycled aggregates utilizing ensemble machine learning models

[EN] This study aims to apply machine learning methods to predict the compression strength of self-compacting recycled aggregate concrete. To obtain this goal, the ensemble methods: Random Forest (RF), K-Nearest Neighbor (KNN), Extremely Randomized Trees (ERT), Extreme Gradient Boosting (XGB), Gradient Boosting (GB), Light Gradient Boosting Machine (LGBM), Category Boosting (CB) and the generalized additive models: Inverse Gaussian (GAM1) and Poisson (GAM2) were applied. For the development of the models, 515 research article samples were collected and divided into three subsets: training (360), validation (77), and testing (78). The SCC components: cement, water, mineral admixture, fine aggregates, coarse aggregates, and superplasticizers were taken as input variables and compression strength as output variables. To determine the ability of the models to project compressive strength, the following metrics were used: R2, RMSE, MAE, and MAPE. The results indicate that the RF (R2 = 0.7128, RMSE = 0.0807, MAE = 0.06) and GB (R2 = 0.6948, RMSE = 0.0832, MAE = 0.0569) models have a strong potential to predict the compressive strength of SCC with recycled aggregates. The sensitivity analysis of the RF model indicates that cement and water are the variables that have the highest impact in predicting the compressive strength, while coarse aggregate has the lowest impact.S

Gut Microbiota Cannot Compensate the Impact of (quasi) Aposymbiosis in Blattella germanica

The German cockroach Blattella germanica is a good model to study complex symbiotic relationships because the following two symbiotic systems coexist in a single individual: the endosymbiont Blattabacterium (living inside specialized cells called bacteriocytes) and the gut microbiota. Although the role of the endosymbiont has been fully elucidated, the function of the gut microbiota remains unclear. The study of the gut microbiota will benefit from the availability of insects deprived of Blattabacterium. Our goal is to determine the effect of the removal (or, at least, the reduction) of the endosymbiont population on the cockroach's fitness, in a normal gut microbiota community. For this purpose, we treated our cockroach population with rifampicin to decrease the amount of endosymbiont in the following generation. As the treatment also affects rifampicin-sensitive gut bacteria, we allowed it to recover for at least 20 days before sampling. We found that after this antibiotic treatment, the endosymbiont population remained extremely reduced and only the microbiota were able to recover, although it could not compensate for the endosymbiont role, and the host's fitness was drastically affected. This accomplished reduction, however, is not homogenous and requires further study to develop stable quasi-aposymbiotic cockroaches

Propuesta de plan de acción en materia de higiene y seguridad ocupacional en taller de Mecánica Automotriz Deshon y Cía, Sucursal Montoya

Presenta un diseño de un plan de acción de higiene y seguridad ocupacional en Taller de Mecánica Automotriz Deshon, Sucursal Montoya. Determina las condiciones en materia de higiene y seguridad ocupacional. Identifica los peligros existentes en las instalaciones. Presenta un plan de acción ante la exposición de riesgo presente

ATP-Dependent Lon Protease Controls Tumor Bioenergetics by Reprogramming Mitochondrial Activity

We generated mice deficient in Lon protease (LONP1), a major enzyme of the mitochondrial quality control machinery. Homozygous deletion of Lonp1 causes early embryonic lethality, whereas its haploinsufficiency protects against colorectal and skin tumors. Furthermore, LONP1 knockdown inhibits cellular proliferation and tumor and metastasis formation, whereas its overexpression increases tumorigenesis. Clinical studies indicate that high levels of LONP1 are a poor prognosis marker in human colorectal cancer and melanoma. Additionally, functional analyses show that LONP1 plays a key role in metabolic reprogramming by remodeling OXPHOS complexes and protecting against senescence. Our findings demonstrate the relevance of LONP1 for cellular and organismal viability and identify this protease as a central regulator of mitochondrial activity in oncogenesis

Factores asociados al índice de reprobación de asignaturas de ciencias básicas del ITSLP

The purpose of the study was to find the factors associated with the failure rate of subjects included in the Basic Science Department that affect students of the “Instituto Tecnológico de San Luis Potosí”, to propose strategies that increase the approval rate in this area. This research had a quantitative approach; statistics were used as a basic tool for the analysis of the data and its relationships, with a descriptive scope. Data from the Comprehensive Information System (Sistema Integral de Información, SII) was used to obtain the failure rates of the subjects in the period from January to June 2020. Through an online survey, the data and their relationships were obtained and analyzed, related to social, personal and institutional factors within their different dimensions. According to the results obtained, the hypothesis established in this research is fulfilled as true: "The social, personal and institutional factors are associated with the failure rate in subjects included in the Basic Sciences Department". Being the Instituto Tecnológico de San Luis Potosí a professional training institution, strategies are suggested, such as forming support groups for consultancies from teachers of the Basic Sciences Department in each subject and following up with students to help lower the high failure rate.La finalidad del estudio fue encontrar los factores asociados al índice de reprobación de las asignaturas del Departamento de Ciencias Básicas que afectan a los estudiantes del Instituto Tecnológico de San Luis Potosí, para proponer estrategias que incrementen el índice de aprobación en esta área. Esta investigación tuvo un enfoque cuantitativo, se utilizó la estadística como herramienta básica para el análisis de los datos y sus relaciones, con un alcance descriptivo. Se emplearon los datos del Sistema Integral de Información (SII), para obtener los porcentajes de reprobación de las asignaturas en el periodo de enero a junio 2020. Mediante una encuesta en línea se obtuvieron y analizaron los datos y sus relaciones, en los factores de origen social, personal e institutional en sus diferentes dimensiones. De acuerdo a los resultados obtenidos “Los factores de origen social, personal e institucional, se encuentran asociados al índice de reprobación en las asignaturas del Departamento de Ciencias Básicas”. De tal manera que siendo una Institución formadora de profesionistas se sugieren estrategias, tales como formar grupos de apoyo para asesorías por parte de los docentes del área de Ciencias Básicas y dar seguimiento a los estudiantes para coadyuvar a bajar el alto índice de reprobación

Evaluación de la calidad del agua en un río subtropical y tributarios utilizando índices fisicoquímicos y macroinvertebrados acuáticos

Background. The evaluation of the integrity of a river involves the analysis of different aspects of its environment and the ecosystem itself. Goal. In the present study, the abiotic and biotic quality of the Cupatitzio river was characterized using multiple indicators. Methods. An analysis of the coverage of the different land uses in the basin was carried out, 16 physicochemical variables of the water were measured, and aquatic invertebrates were identified and quantified in 20 monitoring sites. Water quality index (NSF-WQI) and biological indices (Shannon-Wiener, Pielou, and Indicator Species Analysis) were calculated, and multivariate statistical methods were applied. Results. Most of the sites present an important coverage of human settlements and agriculture, and the lowest value for natural vegetation. Consequently, the beginning of the river presented a modification in its channel which reduced the value of biological indicators. Overall water quality is medium for the river, related to the presence of organic matter with high values of Biochemical Oxygen Demand (maximum 22.82 mg/L) and nutrients (maximum NO3 of 12.39 mg/L and NH4 of 7.31 mg/L). The dominant families were Chironomidae, Lumbriculidae, Gammaridae, and Baetidae. A significant spatial and temporal difference in family abundance was detected (A=0.061, P=0.0007, and A=0.247, P=0.000008, respectively). Six of the 77 families were identified as significant indicators. Conclusions. Only at dry season there was more concordance between environmental quality and aquatic organisms’ indicators. A protocol of the analyses is presented for implementation in other aquatic ecosystems and it is recommended the necessity to calibrate and validate biological indicator indices (e. g., BMWP) to improve interpretation.Antecedentes. La evaluación de la integridad de un río involucra el análisis de diferentes aspectos de su entorno y del propio ecosistema. Objetivos. En el presente estudio se caracterizó la calidad abiótica y biótica del río Cupatitzio utilizando múltiples indicadores. Métodos. Se realizó un análisis de la cobertura de los diferentes usos del suelo en la cuenca, se registraron 16 variables fisicoquímicos del agua, se identificaron y cuantificaron los invertebrados acuáticos en 20 sitios. Se calcularon el índice de calidad del agua (NSFWQI) y los índices biológicos (Shannon-Wiener, Pielou e Indicator Species Analysis) y se aplicaron métodos estadísticos multivariados. Resultados. La mayoría de los sitios presentan una importante cobertura de asentamientos humanos y agricultura con el menor valor para la vegetación natural. En consecuencia, el inicio del río presentó una modificación en su cauce lo que redujo el valor de los indicadores biológicos. La calidad del agua es mayormente media, relacionada a la presencia de materia orgánica con altos valores de Demanda Bioquímica de Oxígeno (máximo de 22.82 mg/L) y nutrientes (máximos de NO3 de 12.39 mg/L y NH4 de 7.31 mg/L). Las familias dominantes fueron Chironomidae, Lumbriculidae, Gammaridae y Baetidae. Se detectó una diferencia significativa tanto espacial como temporal en la abundancia de las familias (A=0.061, P=0.0007 y A=0.247, P=0.000008, respectivamente). Se identificaron 6 de las 77 familias como indicadores significativos. Conclusiones. Solo en estiaje se presentó más concordancia entre la calidad ambiental y los macroinvertebrados indicadores. Se presenta un protocolo de análisis para su implementación en otros ecosistemas acuáticos y se ve la necesidad de incorporar otros índices de indicadores biológicos (p. ej., BMWP) calibrados y validados para mejorar la interpretación

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

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