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Adsorption and Photocatalytic Degradation of Methylene Blue in Carbon Nanotubes: A Review with Bibliometric Analysis

Hugo Albeiro Saldarriaga Noreña MARIO ALFONSO MURILLO TOVAR JOSEFINA VERGARA SANCHEZ JEANNETE RAMIREZ APARICIO Lorena Magallón Cacho MARIA LUISA GARCIA BETANCOURT (2023, [Artículo])

Wastewater-containing dyes are an environmental problem. The prime source of dye pollutants is the textile industry, such as paper manufacturing, food processing, leather, pigments, etc. Dye removal from wastewater using nanotechnology has received attention in recent decades thanks to efficient nanomaterials improving traditional technologies. In recent years, multiple research reports on carbon nanotubes for dye removal and photocatalytic dye degradation provided substantial insight into the comprehension of nanotechnology and remediation. This work presents a review and bibliometric analysis of carbon nanotubes for dye removal and photocatalytic dye degradation, which have an environmental impact today. The bibliometric study showed that the current research tendency on carbon nanotubes applied in dye removal and photocatalysis is still growing. According to research, this work observed that carbon nanotubes for dye removal exhibit high removal and efficient photocatalysis activity, indicating the functionality of nanotechnology for environmental remediation. The analysis of the parameters involved in the removal studies, such as temperature and pH, showed adsorption behavior. The photodegradation of methylene blue demonstrated the photocatalytic activity of carbon nanotubes attributed to the sp2 lattice of graphitic configuration.

BIOLOGÍA Y QUÍMICA QUÍMICA adsorption; carbon nanotubes; methylene blue; photocatalysis; photodegradation of methylene blue

XYZ Micropositioning System Based on Compliance Mechanisms Fabricated by Additive Manufacturing

CARLOS ANDRES FERRARA BELLO Pedro Vargas Chable José Gerardo Vera Dimas Margarita Tecpoyotl Torres (2021, [Artículo])

This article presents the design and implementation of a micropositioning system actuated

by three piezoelectric stacks to control its displacements on XYZ axes. The use of conventional

piezoelectric buzzers allows us to reduce fabrication costs. The working or mobile platform is the base

for objects that will be manipulated, for example, in automated assembling. The micropositioner can

be integrated into a microgripper to generate a complete manipulation system. For micropositioner

fabrication, at first, Polylactic Acid (PLA) was chosen as the structural material, but after simulation

and some experimental tests performed with a micropositioner made of Acrylonitrile Butadiene

Styrene (ABS), it showed larger displacement (approx. 20%) due to its lower stiffness. A third test

was performed with a positioner made with Polyethylene Terephthalate Glycol (PETG), obtaining an

intermediate performance. The originality of this work resides in the geometrical arrangement based

on thermoplastic polymer compliance mechanisms, as well as in the use of additive manufacturing

to fabricate it. An experimental setup was developed to carry out experimental tests. ANSYS™ was

used for simulation.

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS PETG, MEMS, micromanipulation, piezoelectric actuation, hysteresis effect linearization

Heteranthera yucatana (Pontederiaceae), una especie pequeña, hermosa, endémica …. y amenazada

GERMAN CARNEVALI FERNANDEZ CONCHA RODRIGO STEFANO DUNO Ivón Mercedes Ramírez Morillo José Ramón Grande Allende Yeni Celeste Barrios José Luis Tapia Muñoz (2022, [Artículo])

En el año 2000, personal del Herbario CICY detectó en las cercanías de la Zona Arqueológica de Xcambó, al norte del estado de Yucatán, una pequeña planta semi-acuática que llamó la atención de los colectores. Justo a finales del año 2019, unos meses antes del inicio de la pandemia, salimos nuevamente al campo y la volvimos a conseguir. Esta vez nos cuestionamos su identidad, y tras algunas semanas de búsqueda e investigación, comprobamos que se trataba de un nuevo taxón. Este año, después de muchos ires y venires, ha sido establecida como una especie nueva para la ciencia: Heteranthera yucatana. Esta especie se caracteriza entre otras cosas por su reducido tamaño, su distribución limitada al norte del estado de Yucatán y su categoría de riesgo: “En Peligro”.

COMMELINALES IUCN NOVEDAD TAXONOMICA PLANTAS ACUATICAS PENINSULA DE YUCATAN YUCATAN BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) TAXONOMÍA VEGETAL TAXONOMÍA VEGETAL

Effects of geostrophic kinetic energy on the distribution of mesopelagic fish larvae in the southern Gulf of California in summer/fall stratified seasons

FERNANDO CONTRERAS CATALA (2016, [Artículo])

Effects of geostrophic kinetic energy flux on the three-dimensional distribution of fish larvae of mesopelagic species (Vinciguerria lucetia, Diogenichthys laternatus, Benthosema panamense and Triphoturus mexicanus) in the southern Gulf of California during summer and fall seasons of stronger stratification were analyzed. The greatest larval abundance was found at sampling stations in geostrophic kinetic energy-poor areas (<7.5 J/m3), where the distribution of the dominant species tended to be stratified. Larvae of V. lucetia (average abundance of 318 larvae/10m2) and B. panamense (174 larvae/10m2) were mostly located in and above the pycnocline (typically ∼ 40 m depth). In contrast, larvae of D. laternatus (60 larvae/10m2) were mainly located in and below the pycnocline. On the other hand, in sampling stations from geostrophic kinetic energy-rich areas (> 21 J/m3), where mesoscale eddies were present, the larvae of the dominant species had low abundance and were spread more evenly through the water column, in spite of the water column stratification. For example, in a cyclonic eddy, V. lucetia larvae (34 larvae/10m2) extended their distribution to, at least, the limit of sampling 200 m depth below the pycnocline, while D. laternatus larvae (29 larvae/10m2) were found right up to the surface, both probably as a consequence mixing and secondary circulation in the eddy. Results showed that the level of the geostrophic kinetic energy flux affects the abundance and the three-dimensional distribution of mesopelagic fish larvae during the seasons of stronger stratification, indicating that areas with low geostrophic kinetic energy may be advantageous for feeding and development of mesopelagic fish larvae because of greater water column stability. © 2016 Contreras-Catala et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, autumn, Benthosema panamense, Diogenichthys laternatus, environmental factor, environmental parameters, fish, geographic distribution, geostrophic kinetic energy, hydrography, larva, nonhuman, population abundance, population dispersion, pop CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Functional characterization and cellular dynamics of the CDC-42 - RAC - CDC-24 module in neurospora crassa

CYNTHIA LIZZETH ARAUJO PALOMARES (2011, [Artículo])

Rho-type GTPases are key regulators that control eukaryotic cell polarity, but their role in fungal morphogenesis is only beginning to emerge. In this study, we investigate the role of the CDC-42 - RAC - CDC-24 module in Neurospora crassa. rac and cdc-42 deletion mutants are viable, but generate highly compact colonies with severe morphological defects. Double mutants carrying conditional and loss of function alleles of rac and cdc-42 are lethal, indicating that both GTPases share at least one common essential function. The defects of the GTPase mutants are phenocopied by deletion and conditional alleles of the guanine exchange factor (GEF) cdc-24, and in vitro GDP-GTP exchange assays identify CDC-24 as specific GEF for both CDC-42 and RAC. In vivo confocal microscopy shows that this module is organized as membrane-associated cap that covers the hyphal apex. However, the specific localization patterns of the three proteins are distinct, indicating different functions of RAC and CDC-42 within the hyphal tip. CDC-42 localized as confined apical membrane-associated crescent, while RAC labeled a membrane-associated ring excluding the region labeled by CDC42. The GEF CDC-24 occupied a strategic position, localizing as broad apical membrane-associated crescent and in the apical cytosol excluding the Spitzenkörper. RAC and CDC-42 also display distinct localization patterns during branch initiation and germ tube formation, with CDC-42 accumulating at the plasma membrane before RAC. Together with the distinct cellular defects of rac and cdc-42 mutants, these localizations suggest that CDC-42 is more important for polarity establishment, while the primary function of RAC may be maintaining polarity. In summary, this study identifies CDC-24 as essential regulator for RAC and CDC-42 that have common and distinct functions during polarity establishment and maintenance of cell polarity in N. crassa. © 2011 Araujo-Palomares et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

CDC24 protein, guanine nucleotide exchange factor, protein Cdc42, Rac protein, unclassified drug, cell cycle protein, fungal protein, membrane protein, multiprotein complex, protein Cdc42, Rac protein, allele, apical membrane, article, assay, cell me BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

Incidencia de los aspectos socioeconómicos y la percepción de riesgo de contagio de Covid-19 sobre el comportamiento individual

EMMANUEL CHÁVEZ HERNÁNDEZ (2023, [Tesis de maestría])

Este estudio trata de recoger una perspectiva del impacto de la crisis sanitaria sobre la

precariedad socioeconómica a través de la visión del otro, para comprender el pensamiento y

comportamiento respectivo de desacato a las medidas sanitarias. Por ello, utilizamos

conceptualizaciones y técnicas interdisciplinarias que permitieron la apertura a la expresión y

análisis del discurso, desde la perspectiva de los agentes en el entorno local.

Nuestro objetivo fue identificar los factores socioeconómicos que incidieron en el

comportamiento de los comerciantes informales, y contribuyeron a la construcción de la

percepción de riesgo, ante la probabilidad de contraer Covid19, en el centro de Cuernavaca,

Morelos, durante los años 2020-2022. Se describieron los procesos de incidencia y se abordaron

aspectos y momentos específicos contextuales y locales de la crisis sanitaria.

De acuerdo a estos planteamientos utilizamos dos metodologías inductivas, una cualitativa

“Investigación Acción Participativa”, y una cuantitativa “Metodología de la economía

positiva”. De esta manera, el producto obtenido fue un modelo de árbol de toma de decisiones

de comportamientos entre los individuos (basado en los factores socioeconómicos), el cual

relacionamos con el nivel de percepción de riesgo resultante, y mostró el comportamiento de

los actores durante la crisis sanitaria.

CIENCIAS SOCIALES SOCIOLOGÍA Socioeconomía, percepción de riesgo, comercio informal, Covid19, árbol de decisiones

Entrenamiento en servicio en operación de sistemas de riego por gravedad y aspersión en el estado de Guanajuato

Juan Manuel Angeles WALDO OJEDA BUSTAMANTE CARLOS ARMANDO DE LOS SANTOS GARCIA FELIPE BENJAMIN DE LEON MOJARRO (2006, [Documento de trabajo])

El objetivo principal del proyecto fue entrenar a técnicos responsables de realizar extensión agrícola en riego para el manejo adecuado de los sistemas de riego bajo su supervisión, sus diagnósticos y dictámenes respecto al uso eficiente del agua de riego y fertirriego, para que a su vez asesoren a los productores participantes para lograr el uso pleno de la infraestructura de riego y fertirriego en sistemas del estado de Guanajuato.

Riego por gravedad Riego por aspersiíon Capacitación Fertirriego INGENIERÍA Y TECNOLOGÍA

Effect of antimicrobial nanocomposites on Vibrio cholerae lifestyles: Pellicle biofilm, planktonic and surface-attached biofilm

ANAID MEZA VILLEZCAS (2019, [Artículo])

Vibrio cholerae is an important human pathogen causing intestinal disease with a high incidence in developing countries. V. cholerae can switch between planktonic and biofilm lifestyles. Biofilm formation is determinant for transmission, virulence and antibiotic resistance. Due to the enhanced antibiotic resistance observed by bacterial pathogens, antimicrobial nanomaterials have been used to combat infections by stopping bacterial growth and preventing biofilm formation. In this study, the effect of the nanocomposites zeolite-embedded silver (Ag), copper (Cu), or zinc (Zn) nanoparticles (NPs) was evaluated in V. cholerae planktonic cells, and in two biofilm states: pellicle biofilm (PB), formed between air-liquid interphase, and surface-attached biofilm (SB), formed at solid-liquid interfaces. Each nanocomposite type had a distinctive antimicrobial effect altering each V. cholerae lifestyles differently. The ZEO-AgNPs nanocomposite inhibited PB formation at 4 μg/ml, and prevented SB formation and eliminated planktonic cells at 8 μg/ml. In contrast, the nanocomposites ZEO-CuNPs and ZEO-ZnNPs affect V. cholerae viability but did not completely avoid bacterial growth. At transcriptional level, depending on the nanoparticles and biofilm type, nanocomposites modified the relative expression of the vpsL, rbmA and bap1, genes involved in biofilm formation. Furthermore, the relative abundance of the outer membrane proteins OmpT, OmpU, OmpA and OmpW also differs among treatments in PB and SB. This work provides a basis for further study of the nanomaterials effect at structural, genetic and proteomic levels to understand the response mechanisms of V. cholerae against metallic nanoparticles. © 2019 Meza-Villezcas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

bacterial protein, copper nanoparticle, nanocomposite, OmpT protein, OmpU protein, OmpW protein, outer membrane protein A, silver nanoparticle, unclassified drug, zeolite, zinc nanoparticle, antiinfective agent, copper, metal nanoparticle, nanocompos BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

Hidrología de avenidas

ALVARO ALBERTO ALDAMA RODRIGUEZ (2000, [Artículo])

La hidrología de avenidas es un tema que ha cobrado mucha relevancia debido a las inundaciones recientemente provocadas por eventos hidrometeorológicos extremos en todo el mundo. Este artículo presenta los resultados de una serie de investigaciones que el autor y sus colaboradores han obtenido a lo largo de los años en la materia. En particular, se discuten métodos para la estimación de avenidas de diseño en presas y redes de ríos, para el tránsito hidrológico de avenidas en cauces y para el tránsito hidráulico de avenidas en redes de ríos con lagunas de interconexión.

Tránsito inverso Parametrización de avenidas Hidrogramas Probabilidad multivariada INGENIERÍA Y TECNOLOGÍA

El territorio hidroindustrial y la industria automotriz en San Luis Potosí

MONICA JAZMIN FRAGOSO PASALAGUA (2020, [Tesis de maestría])

"En esta investigación se analiza cómo usa y controla el agua la industria automotriz en el territorio en el Corredor Industrial Automotriz en San Luis Potosí. La idea de este estudio es contribuir a los estudios sociales del agua y adentrarse en los entramados de los usos de agua de la industria automotriz."

Automóviles -- Industria y comercio -- San Luis Potosí Agua - Industria Automotriz -- México CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO HIDROLOGÍA HIDROLOGÍA