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A medida que las instituciones educativas retornaron a la presencialidad, se visualizaron brechas en la práctica docente y en el uso de las tecnologías. El objetivo de este estudio fue analizar los desafíos y oportunidades que se presentan en la educación ecuatoriana después de la pandemia desde la perspectiva de la docencia y la tecnología educativa. La investigación se fundamentó desde la teoría, a través de una revisión documental de las bases de datos SciELO y REDALYC sobre los desafíos y oportunidades en la educación ecuatoriana postpandemia. Los hallazgos encontrados fueron el aumento del uso de la tecnología educativa y la necesidad de formación docente para su implementación efectiva, la brecha digital y la exclusión educativa y la redefinición de los roles de los docentes y estudiantes. Se concluye que existe una necesidad de adaptación y flexibilidad en la forma en que se imparte y se evalúa la educación, así como en la formación docente para la implementación efectiva de la tecnología educativa; es decir la educación ecuatoriana en el contexto postpandemia enfrenta desafíos significativos, como oportunidades para la mejora y transformación del sistema educativo.

During the Mexican fold-and-thrust belt tectonics, the inboard migration of long-term cordilleran magmatism typifies the geological setting during the Cretaceous–Paleogene period. The Concepción del Oro Igneous Complex (COIC) represents one of the most internal and isolated magmatic pulses that occurred during this magmatic activity. In this work, plutonic rocks from the COIC were studied using petrography, U–Pb geochronology, whole rock and zircon geochemistry, and Rb–Sr and Sm–Nd isotopes. Petrographic observations reveal mainly fine-to-coarse-grained granodioritic composition for most plutonic masses. U–Pb zircon analyzes of four samples from the largest plutonic center of the COIC yielded ages ranging from 42.6 ± 0.2 Ma to 41.8 ± 0.1 Ma. The granodiorites exhibit geochemical features typical of I-type, high-K calc-alkaline, Magnesian rocks. The chondrite-normalized REE diagram summarizes enrichment of LREE ([La/Yb]N = 5.94–19.19) and moderate to slightly negative Eu anomalies (Eu/Eu* = 0.63–0.94). In addition, the mantle-normalized spider diagram shows enrichment of LILE, such as Rb and Ba, and depletion of HFSE, such as Nb, Ta, Ti, and P. Whole-rock and zircon geochemistry indicate a post-collisional setting with an inherited magmatic arc fingerprint. Ti-in-zircon temperatures and zircon saturation thermometry suggest a magmatic origin from evolved and relatively cold melts (~ 700 °C). Moreover, the systematic variations in the ratios of highly incompatible elements, such as La/Sm (6.54–3.79) and Rb/Sr (0.32–0.10), and relatively narrow ranges in Zr/Hf (36.25–48.84) and 147Sm/144Nd (0.0941–0.1261), suggest fractional crystallization as the main petrogenetic process involved in the formation of the COIC rocks. Whole-rock isotopic data suggest a magma source mixing juvenile material with older continental crust, as indicated by 87Sr/86Sr(t = 40) ratios between 0.704583 and 0.707783, 143Nd/144Nd(t = 40) ratios varying in the ranges of 0.512478–0.512702 (εNd(t = 40) = from + 2.18 to − 2.10), and TDM(Nd) ranging from 1.03 to 0.62 Ga. We conclude that the parental source of the COIC was derived from partial melting of the lower crust triggered by emplacement of an underplated magma at the base of the crust during the end of an orogenic cycle.

Con respecto a Luna (2015). afirma que el proceso de producción de panela ha venido ocasionando impactos negativos al medio ambiente, en especial en la vereda San Isidro del municipio de Ricaurte Colombia, debido a la quema de llantas, leña, plástico, todo esto como materia prima para su posterior evaporación del jugo de la caña en los trapiches paneleros, ya que al quemar este material solido derivado del petróleo, al desintegrarse con el fuego en la cámara de la combustión produce un proceso químico en el cual el Carbono e Hidrogeno del combustible, reaccionan con el Oxigeno del aire, liberando su energía térmica, gases y material particulado, por lo tanto esta reacción es liberado a través del ducto de la chimenea como humo negro llamado hollín causante de la contaminación del medio ambiente. El presente trabajo busca como estrategia pedagógica disminuir los impactos negativos producidos al medio ambiente implementando estrategias como el desarrollo de un manual de buenas prácticas de manufactura, en cuanto a Vanegas C (2016) afirma que el MBPM permite una producción más limpia que contemple todos los componentes de desarrollo sostenible, con el fin mitigar el impacto ambiental generado por la quema de llantas como combustible fósil en los trapiche, lo cual este manual contiene la descripción de la elaboración de la panela, materiales utilizados para el proceso de la combustión, las norma de bioseguridad, sanitarias, con el fin de brindar seguridad a los operarios, reducción de la contaminación ambiental y la salubridad de los pobladores.

Introdução: A sífilis congênita ocorre devido a disseminação hematogênica do Treponema pallidum da gestante infectada não tratada ou inadequadamente tratada para o feto por via transplacentária. Cerca de 80% das transmissões verticais ocorrem intraútero, com taxa de transmissibilidade maior quando a gestante encontra-se portando sífilis primaria ou secundaria. Objetivo: Avaliar o aumento no número de casos de sífilis congênita na Maternidade do Hospital Regional de Taguatinga – HRT, entre o período de julho a dezembro dos anos de 2018 e 2019. Método: Trata-se de um estudo observacional, transversal, descritivo, com coleta de dados retrospectiva no prontuário eletrônico do sistema TrakCare. Foram incluídos RNs com até 28 dias, de ambos os sexos, diagnosticado com sífilis congênita durante o período de julho a dezembro dos anos de 2018 e 2019. Foram coletadas informações referentes a localidade de origem da mãe do RN; data de nascimento do RN, sexo, idade gestacional, APGAR, realização de pré-natal (quantas consultas e quando começou) classificação do RN (AIG, PIG ou GIG), se fez ou não tratamento de sífilis na gestação, tratamento de escolha do RN e desfecho. Resultados: Durante o período do estudo foram incluídos 124 RNs com até 28 dias, de ambos os sexos, diagnosticado com sífilis congênita ou expostos à sífilis durante o período de julho a dezembro dos anos de 2018 (35,5%) e 2019 (64,5%). Cerca de 33,1% das genitoras eram procedentes de Taguatinga e 16,1% de Águas lindas. Cerca de 51,6% dos recém-nascidos eram do sexo masculino e 43,5% eram do sexo feminino. 35,5% dos pacientes foram diagnosticados com Sífilis congênita e 59,7% foram expostos à sífilis. 76,6% dos RNs foram classificados como RNT/AIG. 79% eram a termo. 92,7% tiveram APGAR no primeiro minuto normal e 95,2% tiveram APGAR normal no quinto minuto. Conclusão: conclui-se que, diante do cenário epidemiológico da sífilis no Hospital Regional de Taguatinga, há necessidade de intensificar ações conjuntas com a Atenção primária, objetivando a prevenção dos casos de sífilis congênita no pré-natal. Esta ação contribui para diminuição dos casos de sífilis congênitas na instituição e redução dos gastos públicos com estes pacientes. Não obstante, cabe salientar também que houve um aumento considerável das gestantes provenientes de Águas lindas-GO no ano de 2019. Este aumento de gestante de Águas lindas pode ter contribuído também para o aumento dos casos de sífilis congênita no HRT.

El siguiente articulo refleja los procesos y resultados del trabajo realizado desde el año 2020 para la automatización de un cultivo vertical de Pleurotus Ostreatus para el incremento de cuerpo fructíferos y su posterior análisis para determinar la producción de quitina. El documento presenta el estado del arte de la investigación y el proceso de diseño del sistema de adquisición de datos de temperatura y humedad del cultivo desarrollado. Antecedentes y Objetivos: El interés por el consumo de hongos comestibles ha incrementado en los últimos años por su vinculación a los alimentos funcionales, debido a que son una fuente de fibra vegetal, minerales, vitaminas y quitina, entre otros. Dentro de los hongos comestibles se encuentra Pleurotus ostreatus, cuya pared celular está compuesta principalmente de quitina, un homopolímero de N – acetilglucosamina el cual ha sido utilizado como materia prima para la fabricación de materiales biomédicos como membranas, esponjas, geles, implantes, nanopartículas y nanofibras. Por lo anterior, se propone el cultivo de P. ostreatus como una alternativa para la obtención de este biopolímero para el desarrollo de materiales biomédicos, direccionando el desarrollo tecnológico y técnicas de control electrónico para la optimización de su producción y siendo esta una oportunidad para innovar sobre dicho proceso. Para estimular el crecimiento de Pleurotus ostreatus, se diseña un sistema automático que permite el control de las variables de temperatura y humedad y la producción de quitina durante 40 días de cultivo. Nishihara, Watanabe y Asada (2007), describieron la influencia de la temperatura y de la humedad en la expresión génica de la sintasa quitina clase IV durante la formación de cuerpos fructíferos, los cuales le dan la forma al hongo. Sus resultados mostraron que la modulación de la temperatura (25ºC – 15ºC) durante el cultivo incrementó en 1.8 veces la transcripción de la sintasa quitina y así mismo la producción de la misma. De igual forma, los autores proponen estudios sinérgicos entre la variación de la temperatura y la humedad con una proyección de incrementar la concentración de quitina en 1.9 veces. La automatización del cultivo vertical se desarrolla con el grupo de investigación del SENA CDA - GITAE y su semillero SIPCER en conjunto el grupo de investigación CAPSAB de la Universidad de La Sabana y su semillero INFOSEED. Este trabajo busca el fortalecimiento de las competencias en investigación y desarrollo tecnológico, uniendo esfuerzos y recursos de infraestructura, tecnología y personal para el cumplimiento del objetivo general: Automatizar un cultivo vertical de Pleurotus ostreatus para el incremento de cuerpos fructíferos ricos en quitina.

Thermal comfort has become an important element in the design, construction, and remodeling of buildings, as well as in the understanding of human behavior that considers inhabitants’ mental conditions. The objective of this study is to propose general thermal comfort equations via a rigorous statistical evaluation for regions with hot-humid (HH) and hot-dry (HD) climates. From the information on thermal comfort provided in the specialized literature, 17 equations were gathered for hot-humid climates and nine equations for hot-dry climates. These equations were developed for hot climate conditions in zones where buildings operate with natural ventilation (NV). The statistical analysis includes the normality test of the data distribution, the recognition of outliers, and the applications of significance tests for the comparison of the equation parameters. The equations proposed in this paper can be used to initially evaluate the thermal comfort of buildings in locations where no equations have been developed locally, as well as in the energy evaluations of buildings. The equation proposed in this paper for the hot-humid climate is the following: Tc = 16.9 (±2.19) + 0.37 (±0.08) Tout; that for the hot-dry climate is: Tc = 12.9 (±5.36) + 0.56 (±0.20) Tout. These equations can be used to initially assess the thermal comfort of buildings in locations without locally developed equations, as well as in building energy assessments.

The study of the pre-Mesozoic geological history of NE Mexico offers the opportunity to reconstruct the processes that occurred at the NW margin of Gondwana. The Huizachal–Peregrina Anticlinorium, which is located west of Ciudad Victoria (Tamaulipas) is a regional structure produced during the Cretaceous–Palaeogene Laramide Orogeny. Its eroded core exposes Precambrian and Palaeozoic units that together comprise the Sierra Madre Oriental basement. These units are the Neoproterozoic metamorphic Novillo Complex, the Ordovician Peregrina Tonalite, the metamorphic Pennsylvanian Granjeno Complex, and the sedimentary Silurian–Permian Tamatan Group. Aserradero Rhyolite belongs to the Tamatan Group, occurring between the siliciclastic deposits of the Early Mississippian Vicente Guerrero and the Pennsylvanian Del Monte Formations. The studied rhyolites display geochemical characteristics corresponding to high-K, low-Sr, and S-type granitoid rocks that may have been produced by upper-crustal anatexis from a source similar to that of the Novillo Complex. New LA-ICP-MS U–Pb geochronological analysis on zircons separated from the Aserradero Rhyolite yielded Early to Middle Mississippian crystallisation ages of 347.8 ± 2.7 Ma and 340.7 ± 3.6 Ma, confirming that this acidic unit is in its original stratigraphic position despite the pervasive deformation of the Tamatan Group. Based on the correlation with other Carboniferous–Early Permian magmatic complexes in Mexico and Central America, it is suggested that the Aserradero Rhyolite represents an early stage of a precollisional Carboniferous–Permian peri-Gondwanan arc, occurring also in the Las Delicias, Oaxaquia, the Acatlan Complex, the Maya Block, as well as in the buried crystalline basement along the Western Gulf of Mexico. The assembly of the Precambrian and Palaeozoic basement units from the Huizachal–Peregrina Anticlinorium were integrated with the Ciudad Victoria Block, which was dismembered from Oaxaquia and their peripheral units during the Upper-Jurassic Gulf of Mexico opening.

Since our last publishing, a year has passed and too many things have happened. It’s true that life is movement. However, the feeling is that there is not much new under the sun. With all the nuanc...

Esta investigación parte de la necesidad colombiana de desarrollar el pensamiento crítico, principalmente en niños de educación básica primaria, como respuesta a la creciente problemática de conflictos escolares dentro y fuera de las aulas. Esto puede ser atendido desde la implementación de Filosofía para Niños (FpN), porque a partir del análisis de situaciones cotidianas, algunas de ellas convertidas en anécdotas, el docente promueve habilidades de pensamiento que las argumentan y las pasan por el matiz de la crítica. Este proceso se puede articular con las innovaciones que pretende tanto la legislación colombiana, como la educación contemporánea, generando conciencia en el estudiante de soluciones por la vía concertada, llegando a acuerdos y conciliaciones que aborden el conflicto.

Several approaches can be taken to conduct seismic data inversion. However, usually, these approaches are unable to distinguish vertical and horizontal heterogeneities. Seismic inversion through the singular value decomposition (SVD) method offers an adequate and simple way to improve these traditional inversion models. For this study P and S wave data were acquired at a site located in northeastern Mexico, obtaining their travel times. An inversion algorithm involving the SVD analysis was then developed to establish the seismic velocities of the lithological units. Further, images of compressional and shear-wave velocities ( Vpand Vs, respectively), Vp/ Vsratio, and elastic moduli (bulk, shear and Young's moduli, Lamé's constant, and Poisson's ratio) were obtained. These were compared with two geotechnical soundings positioned over a geophysical profile line. The geological features of the exposed units were recognized on some trenches. Further, seismic images demonstrated correlations with the thickness and distribution of the geological units. Unconsolidated sediments and fine-grain clastic rocks (in the Méndez formation) were clearly distinguished by the high velocity contrast. SVD seismic inversion has shown the ability to distinguish small physical heterogeneities of shallow geological units. Its application in civil engineering, hydrogeology, and to solve soil pollution problems can be relevant.

The origin of the Eastern Mexican Alkaline Province has been explained by landward arc migration and subsequent asthenospheric upwelling after slab roll-back of the Farallon Plate. In this work, we present new petrographic, mineral chemical, geochemical, and geochronological data of the Sierra de San Carlos-Cruillas (SSCC), one of the most important complexes in the province. This information, together with published data, helped us to reinterpret the tectonic processes operating during the generation of this province, as well as the mantle sources involved in the partial melting process. Detailed geochemical analysis suggests the participation of two types of metasomatized mantle regions: a lithospheric source modified by past subduction processes and an asthenospheric source slightly affected by carbonatite-related metasomatism. Variations in the partial melting degrees controlled the extent of magma enrichment in the latter. Major and trace element geochemistry, together with geochronological data and field relations, evinced an older post-orogenic setting related to the arc-like rocks (Eocene) and a younger intraplate extensional environment associated with all enriched igneous rocks (Oligocene-Miocene). Bivariate diagrams of SiO2-trace element ratios and multi-element patterns indicate that magmas from the SSCC complex dominantly evolved through fractional crystallization with a limited crustal contribution. Petrographic and mineral chemistry features suggest that some of these magmas experienced open-system processes (e.g. recharge events) in a complex and dynamic magmatic feeding system. In contrast to the traditional petrotectonic model, we propound that the passage and subsequent foundering of the Hess conjugate under northeastern Mexico resulted in its eclogitization and triggered slab tearing and succeeding detachment. This latter process occasioned mantle upwelling and the partial melting of the two recognized metasomatized mantle sources, thus generating the San Carlos-Cruillas magmatism.

Landslides induced by prolonged rainfalls are frequent mass movements along the northeastern portion of the Sierra Madre Oriental in Mexico, causing significant damage to infrastructure. In this work, we have studied the connection between rainfall and landslides in the Santa Rosa Canyon, a catchment located in the northeastern Mexico. A landslide database triggered by major storms and hurricanes that have hit the region over the past 30 years was analyzed. A total of 92 rainfall events in the Santa Rosa Canyon were studied to determine the amount of precipitation needed to trigger shallow landslides. For each event the duration (D, in hours) and the cumulated rainfall event (E, in mm) were determined by using historical rainfall data from weather stations located near the study area. We have proposed an ED threshold for rainfall-induced landslides with durations 0.5 < D < 120 hours to address the conditions that trigger these events in the study area. On analyzing the obtained threshold, it has been established that almost 60 mm of a daily rainfall accumulation is required to trigger shallow landslides in the study area. This estimation is consistent with other calculations made for areas close to the Santa Rosa Canyon. Finally, we validated the predictive capability of the threshold with a different set of rainfall data that did not result in landslides performing a straightforward receiver operating characteristic analysis. A good approach was obtained, especially for rainfall events with daily measurements. Results could be used as input information in the design of a landslide early warning system for the northeastern Mexico, and replicated for other landslide prone areas in the region.

El siguiente articulo refleja los procesos y resultados del trabajo realizado desde el año 2020 para la automatización de un cultivo vertical de Pleurotus Ostreatus para el incremento de cuerpo fructíferos y su posterior análisis para determinar la producción de quitina. El documento presenta el estado del arte de la investigación y el proceso de diseño del sistema de adquisición de datos de temperatura y humedad del cultivo desarrollado.

In this paper, we study an inventory control model, which is analyzed by means of a difference equation. This model is applied to study the stock of a polyester company. In this company, two types of polyester are manufactured, and it is considered a stochastic demand. In the paper, an optimal policy of production is determined, which minimizes the total expected discounted cost. The one-step cost function is integrated with the following components: production, storage and sale lost. The methodology consists on applied the dynamic programming approach and some results of convex analysis to determine a (R, Q)-optimal policy, where R and Q are positive numbers. R represents the maximum level of production and Q is the minimum stock. Finally, with a company database of monthly sales, we adjust a probability distribution and present a numerical implementation of the optimal. Furthermore, simulations to observe the asymptotic behavior of the stock are illustrated.

The Huizachal–Peregrina Anticlinorium basement of the Sierra Madre Oriental in north-eastern (NE) Mexico comprises a wide variety of Precambrian and Paleozoic units. A granitic unit, described in this work as the Peregrina Tonalite (PTo), intruded the Neoproterozoic Novillo Gneiss, which is the northernmost expression of the Oaxaquia microcontinent. In contrast, the PTo’s contact with the Carboniferous Granjeno Schist is tectonic along vertical faults with a strike-slip component. This Paleozoic lithodeme is part of the Granjeno–Acatlan Belt. The PTo has been described as an orphaned block associated with an enigmatic Carboniferous magmatic arc located along the north-western (NW) margin of Gondwana. In this study, new U–Pb LA–ICP–MS data from PTo zircons included a youngest Late Ordovician (Katian stage) population at 448.8 ± 2.9 Ma, interpreted as the crystallisation age, and an oldest Grenvillian population interpreted as the potential age of its protolith. Additionally, major and trace element concentrations and ratios indicate a link to a continental arc that developed along the NW margin of Gondwana. Given this proposed arc’s age and position, a comprehensive model for the development of the NE Mexican basement without the involvement of exotic or orphaned terranes is now proposed. The PTo outcropping near Ciudad Victoria, Tamaulipas, is interpreted to be part of a previously unreported magmatic arc in NE Mexico established during the Late Ordovician, herein described as the Peregrina–Mochonian Orogeny. It represents an extension of the South American Famatinian arc into Mexico.

Purpose The purpose of this paper is to study planar sensor geometries for the measurement of film thickness in a viscous oil–water flow. The study is relevant due to there are only a few measurement techniques for oil-water flow and these techniques involve oil with low viscosity (close to the water viscosity). Specifically, some techniques have been used in the studies of annular flow (gas–liquid and liquid–liquid flows), but applications in other flow patterns were not encountered. Design/methodology/approach Different sensor geometries were numerically simulated to compare their characteristics and choose the best to measure the water film thickness in the oil–water flow through an impedance-based technique. Finite element method was used for resolving the tridimensional electric field over each sensor. The compared characteristics were the penetration depth, the sensitivity, the minimum spatial resolution (high spatial resolution) and the quasi-linear curve. Findings The best geometry tested has a spatial resolution of 2 × 2 mm, a penetration depth of 700 µm and a quasi-linear response in the measuring range. This geometry was tested by means of conductance and capacitance static experiments. From these experiments, it could be determined that conductance and the capacitance systems are promising for measuring water film thickness in an oil–water flow. Originality/value Several measurement techniques such as micro-PIV, planar laser-induced fluorescence and planar conductive or capacitive sensors that are supposed to be adaptable to the liquid–liquid flow have been proposed recently. Micro-PIV and planar-induced fluorescence need transparent pipes and fluids. On the other hand, conductive or capacitive methods have been only applied to low viscosity fluids. In that context, this paper proposes to study a new technique for non-intrusive measurement of the liquid-liquid flow. The main goal is the validation of the new planar sensor as a reference tool for the development of instrumentation for oilfield application.

Resumen: Este artículo presenta la evaluación de un sistema de tratamiento de aguas residuales perteneciente a la industria manufacturera de bebidas no alcohólicas, carbonatadas y no carbonatadas. El desarrollo de este estudio se llevó a cabo mediante 3 muestreos realizados en los meses de mayo, julio y octubre (donde las operaciones de mantenimiento y limpieza del sistema fueron ejecutadas en julio con el propósito de observar sus implicaciones en octubre) y se muestrearon 6 puntos diferentes de la planta de tratamiento. De las muestras obtenidas se determinó la información INSITU, la presencia de bionutrientes, las características físicas, químicas y los parámetros DBO y DQO, en pro de interpretar su rendimiento en términos de remoción de carga orgánica contaminante y establecer los parámetros de control exigidos por la normativa legal vigente del país para identificar las problemáticas existentes en el sistema, sus posibles causas y el planteamiento de una recomendación como solución teórica de las irregularidades observadas. Se evidenció que la fase de pretratamiento cuenta con un buen desempeño en el desarrollo de las actividades de tratamiento debido a su estabilidad en la temperatura y pH, sin embargo, la generación de lodo residual en esta fase comprende un problema que impacta directamente en el costo de operación y mantenimiento del sistema de tratamiento. El efluente de la planta de producción demostró que la adición de agentes químicos y la tasa de generación de lodo activado frente a las condiciones aerobias del sistema, son el mayor apoyo con el que cuenta la planta para realizar los procesos de degradación en la materia orgánica. La caracterización fisicoquímica de las aguas residuales contribuyó a determinar si los mecanismos pertenecientes al tren de tratamiento desarrollaban sus operaciones unitarias bajo condiciones eficientes para la reducción de carga orgánica. Gracias a lo observado en este estudio, sería beneficioso para el sistema la implementación de estructuras complementarias al tanque homogeneizador y tanque ecualizador, para la reducción en la producción de lodo residual, puesto que este problema al acarrearse desde las estructuras iniciales del tren de tratamiento conlleva a la pérdida de eficiencia en los procesos subsecuentes a este durante todo el sistema. Abstract: The document presented here corresponds to the evaluation of a wastewater treatment system belonging to the manufacturing industry of carbonated and non-carbonated soft drinks. The development of this study was performed through 3 samplings carried out in the months of May, July and October (where the maintenance and cleaning operations of the system were carried out in July with the purpose of observing their implications in October) and 6 different points of the treatment plant were sampled. From the obtained samples, the insitu information was determined, the presence of bionutrients, the physical and chemical characteristics, and the BOD and COD parameters, in order to interpret their performance in terms of removal of contaminating organic load, and establish the control parameters required by the current legal regulations of the country to identify the problems existing in the system, their possible causes and the approach of a recommendation as a theoretical solution to the irregularities observed. It was evidenced that the pretreatment phase has a good performance in the development of treatment activities due to its stability in temperature and pH; however, the generation of residual sludge in this phase comprises a problem that directly impacts on the cost of operation and maintenance of the treatment system. The effluent from the production plant showed that the addition of chemical agents and the generation rate of activated sludge against the aerobic conditions of the system are the greatest support that the plant has to perform the processes of degradation in organic matter. The physicochemical characterization of the wastewater helped determine whether the mechanisms belonging to the treatment train developed their unit operations under efficient conditions for the reduction of organic load. Thanks to what was observed in this study, it would be beneficial for the system to implement complementary structures to the homogenizer tank and equalizer tank, for the reduction in the production of residual sludge, since this problem when being carried from the initial structures of the treatment train entails to the loss of efficiency in the subsequent processes to this throughout the system.

We applied both the ordinary linear regression (OLR) and the new uncertainty weighted linear regression (UWLR) models for the calibration and comparison of a XRF machine through 59 geochemical reference materials (GRMs) and a procedure blank sample. The mean concentration and uncertainty data for the GRMs used for the calibrations (Supplementary Materials) (available here) filewere achieved from an up-to-date compilation of chemical data and their processing from well-known discordancy and significance tests. The drift-corrected XRF intensity and its uncertainty were determined from mostly duplicate pressed powder pellets. The comparison of the OLR (linear correlation coefficient r∼0.9523–0.9964 and 0.9771–0.9999, respectively, for before and after matrix correction) and UWLR models (r∼0.9772–0.9976 and 0.9970–0.9999, respectively) clearly showed that the latter with generally higher values of r is preferable for routine calibrations of analytical procedures. Both calibrations were successfully applied to rock matrices, and the results were generally consistent with those obtained in other laboratories although the UWLR model showed mostly narrower confidence limits of the mean (slope and intercept) or lower uncertainties than the OLR. Similar sensitivity (∼2.69–46.17 kc·s−1·%−1 for the OLR and ∼2.78–59.69 kc·s−1·%−1 for the UWLR) also indicated that the UWLR could advantageously replace the OLR model. Another novel aspect is that the total uncertainty can be reported for individual chemical data. If the analytical instruments were routinely calibrated from the UWLR model, this action would make the science of geochemistry more quantitative than at present.

Se presenta una breve revisión de las características químicas generales de la Luna, así como el análisis estadístico multivariado de una base de datos de basaltos lunares y las implicaciones de este ejercicio en el origen y la estructura del satélite natural.

From samples of the Paleozoic Tamatan Group (Huizachal-Peregrina Anticlinorium, Tamaulipas, Mexico), petrographic (qualitative and modal) and geochemical analyses (major, trace, and rare earth elements) were conducted. The first U-Pb geochronological data on detrital zircons of the Tamatan Group were generated using four samples. The data presented here contains a broad overview of photomicrography, recalculated modal point-count data, raw geochemical data, and simple statistics of selected geochemical parameters. The data presented in this article are interpreted and discussed in the research article titled "Provenance and tectonic setting of the Tamatan Paleozoic sequence, NE Mexico: Implications for the closure of the Rheic Ocean at the northwestern part of Gondwana" [1].