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Rainfall water quality at Atlixco, Puebla

Margarita Teutli Andrés Armando Sánchez Erendira Moreno Gutierrez (2021, [Artículo, Artículo])

This work reports the follow up of rainfall water quality at Atlixco, Puebla during the 2018 season. The main objective of this work was to evaluate how height and pollutants define the quality of water precipitated. Samples were collected at the roof of a house in Atlixco center, and others at the roof of a convent located at the San Miguel Hill, this represents a 44 m difference in height. Chemical composition was analyzed for 19 physicochemical parameters using gravimetric and spectrophotometric techniques. Obtained results were compared with drinking water standards finding that Pb and Cd contents are exceeded. Also, it was found a strong contribution of terrestrial sources since the marine rates are above unit, as well as excess concentrations whose values go from negative to positive. Finally, Pearson correlation was obtained finding that most of chemical parameters correlations are in disagreement for both sites, fact which confirms that ionic content is strongly influenced by anthropogenic sources.

rainfall ionic content marine rates excess concentrations Lluvia contenido iónico cociente marino concentración en exceso Estudios urbanos CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Monitoreo de playas prioritarias

NORMA RAMIREZ SALINAS JUAN LEODEGARIO GARCIA ROJAS (2012, [Documento de trabajo])

Se presentan los resultados obtenidos en la prueba, para Enterococos en agua de mar, llevada a cabo en 37 playas de Campeche, Chiapas, Guerrero, Jalisco, Nayarit y Veracruz.

Control de calidad del agua Análisis bacteriológico Agua de mar Campeche Chiapas Guerrero Jalisco Nayarit Veracruz INGENIERÍA Y TECNOLOGÍA

Presencia de Perkinsus marinus en el ambiente y en los moluscos Anadara tuberculosa, Mytella strigata y Crassostrea corteziensis de la costa de Nayarit

Presence of Perkinsus marinus in the environment and in the mollusks Anadara tuberculosa, Mytella strigata and Crassostrea corteziensis from the coast of Nayarit

Naoki Abraham Kawamoto Camacho (2023, [Tesis de maestría])

El parásito Perkinsus marinus cuyo ciclo de vida le permite subsistir en el ambiente y cumplir su ciclo dentro del hospedero es el agente causal de la perkinsosis, letal para Crasssotrea virginica y enlistado por la Organización Mundial de Salud Animal (OMSA). El comercio de ostiones entre el Golfo de México y el Pacífico mexicano ha generado preocupaciones sanitarias al introducir estos moluscos en comunidades costeras del Pacífico. P. marinus formaría parte de la microbiota ambiental y estar en los moluscos bivalvos de estos ambientes. En el presente estudio se emplearon las técnicas PCR, qPCR, secuenciación de amplicones y de próxima generación, así como análisis de microbioma para determinar la presencia de P. marinus en el ambiente y en los moluscos Anadara tuberculosa, Mytella strigata y Crassostrea corteziensis que coexisten en el estero Pozo Chino, Nayarit. Además, se analizaron muestras embebidas en parafina de Tabasco, Veracruz (C. virginica), Nayarit y Sinaloa (C. corteziensis) para realizar comparaciones genotípicas. La prevalencia de infección mediante PCR fue de 86% en ostiones de la zona baja y media del estero, y de 66% en la zona alta, mientras que para M. strigata fue de 2.2% por qPCR. No se detectó a P. marinus en el ambiente ni en A. tuberculosa. La identidad del parásito fue de 86.1 al 100% mediante secuenciación dirigida. Los primers que amplifican productos de 130 pb fueron más eficaces. La no detección del parásito en el entorno se debe a su baja presencia, consecuencia de la baja salinidad, ausencia de infecciones graves y la falta de eventos inusuales de mortalidad, evitando la liberación masiva del parásito en el ambiente. Además, la baja detección en M. strigata y ausencia en A. tuberculosa puede relacionarse con su susceptibilidad. El análisis del microbioma eucariótico mostró a P. marinus como parte de la microbiota en C. corteziensis. En el ambiente los grupos más abundantes fueron copépodos, moluscos, poliquetos y diatomeas. Se requiere profundizar en su estudio en el ambiente y hospederos a lo largo del año para dimensionar mejor el riesgo sanitario que se enfrenta en una zona donde se ha establecido el parásito.

The parasite Perkinsus marinus, whose life cycle allows it to survive in the environment and complete its cycle within the host, is the causative agent of perkinsosis, lethal to Crassostrea virginica, and listed by the World Organisation for Animal Health (WOAH). The trade of oysters between the Gulf of Mexico and the Mexican Pacific coast has raised sanitary concerns by introducing these mollusks into coastal communities on the Pacific. In areas where detection has occurred, P. marinus would be part of the environmental microbiota (plankton/sediments) and in coexisting bivalve mollusks. In this study, PCR, Real-Time PCR (qPCR), amplicon sequencing and next-generation sequencing techniques, as well as microbiome analysis, were employed to determine the presence of P. marinus in the environment (plankton and sediments) and in the mollusks Anadara tuberculosa, Mytella strigata, and Crassostrea corteziensis coexisting in the Pozo Chino estuary, Nayarit. Paraffin-embedded samples from Tabasco, Veracruz (C. virginica), Nayarit, and Sinaloa (C. corteziensis) were also analyzed for genotypic comparisons. The infection prevalence through PCR was 86% in oysters from the lower and middle zones of the estuary and 66% in the upper zone, while for M. strigata, it was 2.2% by RT-PCR. P. marinus was not detected in the environment or in A. tuberculosa. Directed sequencing revealed a parasite identity of 86.1 to 100%. Primers amplifying 130 bp products were more effective. The lack of detection of the parasite in the environment is due to its low presence, resulting from low salinity, the absence of records of severe infections, and the lack of unusual mortality events, preventing massive release of the parasite into the environment. Additionally, the isolated detection in M. strigata and absence in A. tuberculosa may be related to their susceptibility. Analysis of eukaryotic microbiomes identified P. marinus as part of the microbiota in C. corteziensis. In the environment, the most abundant groups were copepods, mollusks, polychaetes, and diatoms. Further studies in the environment and hosts throughout the year are required to better understand the health risks in an area where the parasite has become established.

Perkinsus marinus, Anadara tuberculosa, Mytella strigata, Crassostrea, protista, Pozo Chino, susceptibilidad Perkinsus marinus, Anadara tuberculosa, Mytella strigata, Crassostrea, protist, Pozo Chino, susceptibility CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA ACUICULTURA MARINA OCEANOGRAFÍA ACUICULTURA MARINA

Arreglos de antenas para radiación tipo Isoflux en satélites LEO con diferentes alturas orbitales

Antenna arrays for Isoflux radiation in LEO satellites at various orbital altitudes

Paulina Díaz De la Paz (2023, [Tesis de maestría])

En los últimos años, las constelaciones de satélites en órbita baja han ganado popularidad como infraestructura para ofrecer el servicio de Internet satelital, y se espera que su presencia siga en aumento. Para minimizar la latencia en la transmisión de datos, estos satélites suelen situarse en el rango inferior y medio de la órbita baja terrestre. Comúnmente, los satélites de estas constelaciones emiten una radiación que consiste en un único haz que concentra la potencia en una sola dirección. Sin embargo, debido a la curvatura de la Tierra, las ondas electromagnéticas radiadas por el arreglo de antenas abordo del satélite viajan distancias diferentes. Las ondas que se desplazan en dirección del nadir del satélite hacen un recorrido más corto en comparación con las que se propagan en las direcciones más distantes a este. Este fenómeno ocasiona pérdidas de potencia en los bordes del área de cobertura. Para compensar estas pérdidas, se propone el uso de arreglos de antenas de radiación tipo Isoflux. Estos arreglos distribuyen la densidad de potencia de manera uniforme en el área de cobertura, aumentando la ganancia en direcciones donde el trayecto es más largo. Lograr este tipo de radiación para satélites en órbita baja se vuelve más desafiante. Debido a la proximidad del satélite a la Tierra, es necesario que la radiación se extienda sobre una gran parte del plano de elevación, requiriendo un haz Isoflux que sobrepasa los 100 grados. Esta tesis presenta 18 diseños de arreglos de antenas para satélites en las alturas orbitales de 340 km, 550 km y 1150 km. Para el diseño de estos arreglos, se emplean las geometrías lineales, planares y anillos concéntricos, tanto periódicas como aperiódicas. La distribución de excitaciones de amplitud y la separación entre elementos de antena se optimizan utilizando algoritmos genéticos. La presente tesis incluye un análisis comparativo de las prestaciones de radiación y cantidad de elementos de los diseños presentados, categorizados por altura orbital.

In recent years, the utilization of low-Earth orbit satellite constellations as infrastructure for providing satellite Internet services has experienced substantial growth. The rise of this trend is likely to continue. These satellites are typically placed in the lower to mid-range of low-Earth orbit in order to reduce latency in data transmission. It is common for the antenna arrays on these satellites to emit a single radiation beam that concentrates power in a singular direction. Due to the curvature of the Earth, the electromagnetic waves radiated by the antenna array travel different distances. Waves traveling in the satellite’s nadir direction cover a shorter distance compared to those propagating in more distant directions. This phenomenon causes power losses at the edges of the coverage area. To compensate for these losses, the use of Isoflux radiation antenna arrays is proposed. These arrays distribute the power density evenly across the coverage area, increasing gain in directions where the path is longer. Achieving such radiation characteristics becomes more difficult for low-Earth orbit satellites. Due to the satellite’s proximity to Earth, radiation needs to extend over a large portion of the elevation plane, requiring an Isoflux beam that exceeds 100 degrees. This thesis presents 18 antenna array designs for satellites at the orbital altitudes of 340 km, 550 km, and 1150 km. Linear, planar, and concentric ring geometries are employed, with both periodic and aperiodic antenna element distributions. The distribution of amplitude excitations and the spacing between antenna elements are optimized using genetic algorithms. This thesis includes a comparative analysis of the radiation performance and the number of elements of the presented designs, categorized by orbital altitude.

arreglos de antenas, radiación Isoflux, satélites LEO, algoritmos genéticos antenna arrays, Isoflux radiation, LEO satellites, genetic algorithms INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA ELECTRÓNICA ANTENAS ANTENAS

Local markets and food security. The case of the Milpera and Puuc regions in Yucatan

Ana Laura Bojórquez Carrillo Monserrat Vargas Jiménez Mireya Noemi Hernández Islas (2023, [Artículo, Artículo])

Food insecurity is a complex problem worldwide. A major part of this problem is the food supply. Local markets can represent a strategy for building social capital, as well as strategies for subsistence and sustainability of food value chains, contributing to food security and its effects. The objective of this research is to determine if the existence of a municipal market in the Milpera and Puuc regions of Yucatán favors the existence of food security, the consumption or the expense of natural foods. The population is located in 18 municipalities of Yucatán, Mexico. To carry out this study, a cross-sectional, non-experimental study, with a quantitative approach and correlational scope. The main techniques that were applied were descriptive statistics and contingency tables with respect to 6 hypotheses. This work shows that the existence of markets in the communities makes a significant difference because it positively impacts the food security of the inhabitants, since it allows them to have access to a wider variety of products and at the same time, favors the active dynamics of the economy of the community.

Local markets Food safety Local development Food sovereignty Rural areas Mercados locales Seguridad alimentaria Desarrollo local Soberanía alimentaria Zonas rurales CIENCIAS SOCIALES CIENCIAS SOCIALES

The public-private confluence of interests between urban and real estate marketing. The case of the Mitikah Ciudad Viva project

ANA PAULA MONTES RUIZ (2021, [Artículo, Artículo])

The shift from a managerial to an entrepreneurial approach establishes a new form of urban governance based on a broader coalition of forces in which public-private partnerships have taken place. The Xoco-Mitikah urban conflict shows that the confluence of interests between the real estate and urban tourism industry embraces the common goal of designing an urban experience that makes the competitive advantages of Southern Mexico City profitable for both. Mitikah’s real estate marketing analysis showed that, through the promotion highlights of the South, the conflictive socio-territorial relationships that emerge along with the construction of real estate megaprojects are emotionally and affectively mediated.

urban conflict real estate marketing social media urban tourism conflicto urbano marketing inmobiliario redes sociales turismo urbano HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA