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Data for the synthesis, characterization, and use of xerogels as adsorbents for the removal of fluoride and bromide in aqueous phase

NAHUM ANDRES MEDELLIN CASTILLO ELIZABETH DIANE ISAACS PAEZ Liliana Giraldo Gutiérrez JUAN CARLOS MORENO-PIRAJAN ITZIA RODRIGUEZ MENDEZ SIMON YOBANNY REYES LOPEZ JAIME REYES HERNANDEZ SONIA JUDITH SEGOVIA SANDOVAL (2022, [Artículo])

"Groundwater with high fluoride concentrations has been recognized as one of the serious concerns worldwide. Besides, the fluoride released into the groundwater by slow dissolution of fluoride-containing rocks, various industries also contribute to fluoride pollution [1]. Excess intake of fluoride leads to various health problems such as dental and skeletal fluorosis, cancer, infertility, brain damage, thyroid diseases, etc. [2]. On the other hand, bromide is naturally present in surface and groundwater sources. However, during the chlorination process, bromide can be oxidized to HOBr, which can react with natural organic matter in water to form brominated organic disinfection byproducts, which are very harmful to human health [3]. Among various methods for water treatment, the adsorption process has been widely used and seems to be an efficient and attractive method for the removal of many contaminants in water, such as anions, in terms of cost, simplicity of design, and operation [4,5]. In the past years, xerogels and carbon xerogels, a new type of adsorbents, which are synthesized by the sol-gel polycondensation of resorcinol and formaldehyde, have gained attention due to their moldable texture and chemical properties [6]. Moreover, melamine addition in resorcinol and formaldehyde xerogels adds basic groups on its surface, favouring Lewis acid-base interactions between xerogels and other components by adsorption [7]. In this data article, the synthesis of three resorcinolformaldehyde (R/F) xerogels with an increasing amount of melamine (M) was carried out by colloidal polymerization (molar ratios of M/R = 0.5, M/R = 1.0, and M/R = 2.0). Additionally, samples of M/R = 0.5 xerogel were carbonized at 400, 450, and 550 degrees C under an inert atmosphere to increase their specific area. Organic and carbon xerogels obtained were characterized by FTIR, TGA, SEM, Physisorption of N 2, and the pH at the point of zero charge (pH PZC). All organic xerogels were also tested as adsorbents on the removal of fluoride and bromide ions from aqueous phase. The Freundlich, Langmuir, and Radke-Prausnitz isotherm models were applied to interpret the experimental data from adsorption equilibrium. Additionally, the data of the mass of the xerogel needed to remove fluoride and bromide from groundwater and fulfill the maximum concentration levels are also included."

Xerogels Melamine Colloidal polymerization Fluoride and bromide ions Adsorption BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA

Corrigendum: The sole DNA ligase in Entamoeba histolytica is a high-fidelity DNA ligase involved in DNA damage repair

ELISA IRENE AZUARA LICEAGA Abigail Betanzos CESAR SALVADOR CARDONA FELIX ELIZABETH JACQUELINE CASTAÑEDA ORTIZ HELIOS CARDENAS HERNANDEZ ROSA ELENA CARDENAS GUERRA GUILLERMO PASTOR PALACIOS GUILLERMINA GARCIA RIVERA DAVID HERNANDEZ ALVAREZ CARLOS HUMBERTO TRASVIÑA ARENAS Corina Diaz Quezada Esther Orozco Luis Gabriel Brieba de Castro (2022, [Artículo])

"A Corrigendum on

The soleDNA ligase in Entamoeba histolytica is a high-fidelity DNA ligase involved in DNA damage repair

By Azuara-Liceaga E, Betanzos A, Cardona-Felix CS, Castañeda-Ortiz EJ, Cárdenas H, Cárdenas-Guerra RE, Pastor-Palacios G, García-Rivera G, Hernández-Álvarez D, Trasviña-Arenas CH, Diaz-Quezada C, Orozco E and Brieba LG (2018) Front. Cell. Infect. Microbiol. 8:214. doi: 10.3389/fcimb.2018.00214"

EhDNAlig Protozoan DNA insults Ligation Repairing 8-oxoG adduct NER and BER pathways BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

Structural analysis evaluationfor rollers of chassis dynoUsing finite element software

Jesús Emmanuel López Rizo ALFREDO CHAVEZ LUNA JAIME GONZALO SANTANA ESQUIVEL (2023, [Artículo])

This paper discusses the design considerations for a chassis dynamometer, focused on the rollers system used for measuring the power and torque of a vehicle in a university-level workshop. The design must prioritize factors such as safety, ease of use, adaptability to diverse types of vehicles, and the inclusion of safety systems to protect students and the vehicle. The work suggests adaptative features for the design, such as an adjustable fastening system and a compact and portable design, to adapt the structure into a university laboratory. The study also describes common methods for measuring engine power and torque using a chassis dynamometer, and the accurate and reliable measurement systems used for this purpose. This concludes with a discussion of the manufacturing methods used for the chassis dynamometer and a static analysis of the maximum effort capacity in each roller using Von Mises and Goodman fatigue theories. Developing a chassis dynamometer, in accordance the current patents available for workshop practices in a university is essential for providing students with comprehensive training.

Chassis dynamometer Conceptual design Finite element software Power and torque measurement Structural analysis INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Do provisioning ecosystem services change along gradients of increasing agricultural production?

Ronju Ahammad Stephanie Tomscha Sarah Gergel Frédéric Baudron Jean-Yves Duriaux Chavarría Samson Foli Dominic Rowland Josh Van Vianen Terence Sunderland (2024, [Artículo])

Context: Increasing agricultural production shapes the flow of ecosystem services (ES), including provisioning services that support the livelihoods and nutrition of people in tropical developing countries. Although our broad understanding of the social-ecological consequences of agricultural intensification is growing, how it impacts provisioning ES is still unknown. Objectives: We examined the household use of provisioning ES across a gradient of increasing agricultural production in seven tropical countries (Bangladesh, Burkina Faso, Cameroon, Ethiopia, Indonesia, Nicaragua and Zambia). We answered two overarching questions: (1) does the use of provisioning ES differ along gradients of agriculture production ranging from zones of subsistence to moderate and to high agriculture production? and (2) are there synergies and/or trade-offs within and among groups of ES within these zones? Methods: Using structured surveys, we asked 1900 households about their assets, livestock, crops, and collection of forest products. These questions allowed us to assess the number of provisioning ES households used, and whether the ES used are functionally substitutable (i.e., used similarly for nutrition, material, and energy). Finally, we explored synergies and trade-offs among household use of provisioning ES. Results: As agricultural production increased, provisioning ES declined both in total number and in different functional groups used. We found more severe decreases in ES for relatively poorer households. Within the functional groups of ES, synergistic relationships were more often found than trade-offs in all zones, including significant synergies among livestock products (dairy, eggs, meat) and fruits. Conclusions: Considering landscape context provides opportunities to enhance synergies among provisioning services for households, supporting resilient food systems and human well-being.

Agricultural Production Zones Agricultural Intensifcation Synergies and Trade-Offs Landscape Multifunctionality Social-Ecological Systems CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURE INTENSIFICATION ECOSYSTEM SERVICES LANDSCAPE SOCIAL-ECOLOGICAL RESILIENCE ECOSYSTEM SERVICES

Mapas y esferas que redibujaron el mundo: el arribo de Cristóbal Colón a Cipango

JUAN ANTONIO LAVIADA (2023, [Capítulo de libro])

Universidad Autónoma Metropolitana (México). Unidad Azcapotzalco. División de Ciencias y Artes para el Diseño. Departamento de Evaluación del Diseño en el Tiempo. Área de Estudios Urbanos.

Desde su arribo a las islas, Colón estaba convencido de estar en las cercanías de Cipango, nada parecía convencerlo de lo contrario; todo lo que observa lo interpreta desde su convicción de estar en Asia. En el primer apartado de este capítulo se intentará demostrar tomando como referencia los escritos del propio Cristóbal Colón que éste consultó cartas de navegación, esferas e incluso tenía la firme intención de realizar una carta de navegación con el fin de mostrar la ubicación de Cipango. El segundo apartado refiere al hecho de que la única fuente documental sobre Cipango de la cual se tenía noticia dependía exclusivamente de narraciones de Marco Polo y se debatirá si Colón conoció o no dichos relatos.

Cartography--America--History. America--Discovery and exploration. Columbus, Christopher--Influence. Cartografía -- Historia. GA401 CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOGRAFÍA CARTOGRAFÍA GEOGRÁFICA

Sentido y significación del habla en la actuación

Claudia Fragoso Susunaga (2023, [Capítulo de libro])

Capítulo número 2 de la Sección El juego de los signos.

El objetivo de este texto es identificar los elementos de los actos de habla y la pragmática lingüística, que tienen que ver con procesos de significación e intención en la enunciación de un texto dramático-escénico o de algún personaje, pensando en las actividades de doblaje, radio-drama, videojuegos, audiolibros y la escena misma. Desarrollando, desde una visión transdisciplinaria la interacción de diferentes campos del conocimiento, como lo son el teatro, la semiótica y la lingüística e incluso todas aquellas disciplinas humanas que comprenden el habla y su interés en los procesos de comunicación. Las repercusiones de este análisis pueden recaer directamente en la formación y desempeño actoral, favoreciendo procesos de análisis de texto, en función a un enriquecimiento de la expresión comunicativa de actores y actrices.

Discourse analysis. Discourse analysis, Literary. Voice actors and actresses. Modality (Linguistics) Semiotics--Social aspects. Actores y actrices de doblaje. Análisis del discurso literario. Modalidad (Lingüística) Semiótica. PC5252 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA DE LAS BELLAS ARTES

Historical use of water resources. Civil works evolution in Zacatecas state

Carlos Bautista-Capetillo Georgia González-Pérez Hiram Badillo-Almaraz (2021, [Artículo, Artículo])

Availability and demand are essential aspects for the human being when planning is made to provide water to the different sectors that may have need of it; still, the demand of suitable volume of water increases day by day, while the supply decreases gradually. In this inverse relationship, anthropogenic and environmental dynamics are decisive to guarantee the needs of the population, specifically due to the climatic transformations evidenced in recent decades. Throughout history, the state of Zacatecas has suffered the ravages of extreme environmental events, mainly those related to drought. Likewise, but on a lesser extent, severe floods have occurred that have caused socioeconomic damage. In this work, the climatic variations of temperature and precipitation and their influence on the evolution of hydraulic systems for the supply of drinking water in the municipality of Nochistlán de Mejía, Zacatecas are analyzed during the period 1930-2015.

drinking water supply historical development of waterworks climate and its transformations Abasto de agua potable desarrollo histórico de obras hidráulicas clima y sus transformaciones CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Sustainability evaluation of contrasting milpa systems in the Yucatán Peninsula, Mexico

Santiago Lopez-Ridaura Tania Carolina Camacho Villa (2023, [Artículo])

The milpa agroecosystem is an intercropping of maize, beans, squash and other crops, developed in Mesoamerica, and its adoption is widely variable across climates and regions. An example of particular interest is the Yucatan Peninsula in Mexico, which holds highly diverse milpas, drawing on ancestral Mayan knowledge. Traditional milpas have been described as sustainable resource management models, based on long rotations within a slash-and-burn cycle in forest areas. Nevertheless, due to modernization and intensification processes, new variants of the approach have appeared. The objective of this study was to evaluate the sustainability of three milpa systems (traditional, continuous, and mechanized) in four case studies across the Peninsula, with emphasis on food self-sufficiency, social inclusion and adoption of innovations promoted by a development project. The Framework for the Evaluation of Agroecosystems using Indicators (MESMIS, for its Spanish acronym) was used for its flexible, participatory approach. A common group of indicators was developed despite regional differences between study cases, with a high level of farmer participation throughout the iterative process. The results show lower crop yields in traditional systems, but with lower inputs costs and pesticide use. In contrast, continuous milpas had higher value in terms of crop diversity, food security, social inclusion, and innovation adoption. Mechanized milpas had lower weed control costs. Profitability of cash crops and the proportion of forest were high in all systems. Highly adopted innovations across milpa types and study cases included spatial crop arrangement and the use of residues as mulches. However, most innovations are not adapted to local conditions, and do not address climate change. Further, women and youth participation is low, especially in traditional systems.

Milpa Intensification Processes Women and Youth Participation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SUSTAINABILITY INTERCROPPING FOOD SECURITY INNOVATION SOCIAL INCLUSION AGROECOSYSTEMS CASE STUDIES

Risk aversion, impatience, and adoption of conservation agriculture practices among smallholders in Zambia

Hambulo Ngoma João Vasco Silva Frédéric Baudron Isaiah Nyagumbo Christian Thierfelder (2024, [Artículo])

Sustainable agricultural practices such as conservation agriculture have been promoted in southern Africa for nearly three decades, but their adoption remains low. It is of policy interest to unpack behavioural drivers of adoption to understand why adoption remains lower than anticipated. This paper assesses the effects of risk aversion and impatience on the extent and intensity of the adoption of conservation agriculture using panel data collected from 646 households in 2021 and 2022 in Zambia. We find that 12% and 18% of the smallholders were impatient and risk averse, respectively. There are two main empirical findings based on panel data Probit and Tobit models. First, on the extensive margin, being impatient is correlated with a decreased likelihood of adopting combined minimum-tillage (MT) and rotation by 2.9 percentage points and being risk averse is associated with a decreased propensity of adopting combined minimum tillage (MT) and mulching by 3.2 percentage points. Being risk averse is correlated with a decreased chance of adopting basins by 2.8 percentage points. Second, on the intensive margin, impatience and risk aversion are significantly correlated with reduced adoption intensity of basins, ripping, minimum tillage (MT), and combined MT and rotation by 0.02–0.22 ha. These findings imply a need to embed risk management (e.g., through crop yield insurance) in the scaling of sustainable agricultural practices to incentivise adoption. This can help to nudge initial adoption and to protect farmers from yield penalties that are common in experimentation stages.

Risk and Time Preferences CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA TECHNOLOGY ADOPTION RISK SUSTAINABLE INTENSIFICATION SMALLHOLDERS

Impact of automation on enhancing energy quality in grid-connected photovoltaic systems

Virgilio Alfonso Murillo Rodríguez NOE VILLA VILLASEÑOR José Manuel Robles Solís OA Guirette-Barbosa (2023, [Artículo])

Rapid growth in the integration of new consumers into the electricity sector, particularly in the industrial sector, has necessitated better control of the electricity supply and of the users’ op-erating conditions to guarantee an adequate quality of service as well as the unregulated dis-turbances that have been generated in the electrical network that can cause significant failures, breakdowns and interruptions, causing considerable expenses and economic losses. This research examines the characteristics of electrical variations in equipment within a company in the industrial sector, analyzes the impact generated within the electrical system according to the need for operation in manufacturing systems, and proposes a new solution through automation of the regulation elements to maintain an optimal system quality and prevent damage and equipment failures while offering a cost-effective model. The proposed solution is evaluated through a reliable simulation in ETAP (Energy Systems Modeling, Analysis and Optimization) software, which emulates the interaction of control elements and simulates the design of electric flow equipment operation. The results demonstrate an improvement in system performance in the presence of disturbances when two automation schemes are applied as well as the exclusive operation of the capacitor bank, which improves the total system current fluctuations and improves the power factor from 85.83% to 93.42%. Such a scheme also improves the waveform in the main power system; another improvement result is when simultaneously operating the voltage and current filter together with the PV system, further improving the current fluctuations, improving the power factor from 85.83% to 94.81%, achieving better stability and improving the quality of the waveform in the main power grid.

This article belongs to Special Issue Advances and Optimization of Electric Energy System.

Power quality Capacitor bank Voltage and current filter Photovoltaic system INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS