Microbiological Analysis of the Air in a Popular Fish Processing and Marketing Area

Angélica Sinaí Quintanilla Martínez Lizet Aguirre Güitrón Luis Daniel Espinosa Chaurand MAYRA DIAZ RAMIREZ ALEJANDRO DE JESUS CORTES SANCHEZ (2022, [Artículo])

"Fish are marketed as a food and consumed worldwide. During the production of food, contamination by microorganisms is possible through the air, soil, water, surfaces, food handlers, etc. The air does not have a natural microbial composition, but it is a vehicle for the transmission of microorganisms of economic and health interest because they are associated with food spoilage and human diseases. The objective of this study was the microbiological analysis of the air in an area popular for the processing and marketing of fish products in the city of Tepic Nayarit. Using the passive or sedimentation method to collect microorganisms present in the air, the proportion of aerobic mesophile bacteria, coliform bacteria, fungi and yeast was determined at different locations in the fish processing and marketing area for four weeks. The results indicated that the aerobic mesophiles had the highest counts among all the microbial groups analyzed at the twelve different sampling points during the four weeks of the study; their numbers ranged from 2.44 to 2.95 log CFU/m3/h, followed by molds with counts from 1.44 to 2.75 log CFU/m3/h, yeasts with counts from 0.7 to 2.01 log CFU/m3/h and coliforms with counts that ranged from 0.7 to 1.68 log CFU/m3/h. We determined the proportion of the viable microbiological population present in the air at the different sampling points of the study area; several of these sampling points presented values above those recommended by various agencies around the world. Knowledge of the biological hazards transported through the air is important to establish and reduce the risk to the health of occupants and the contamination pathways of processed and marketed fishery products that may be associated with spoilage and foodborne diseases."

food safety, food quality, air pollution, airborne biohazard, environmental monitoring INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ALIMENTOS HIGIENE DE LOS ALIMENTOS HIGIENE DE LOS ALIMENTOS

Potential of Debaryomyces hansenii Strains on the Inhibition of Botrytis cinerea in Blueberry Fruits (Vaccinium corymbosum L.)

SURELYS RAMOS BELL Luis Guillermo Hernández Montiel RITA MARIA VELAZQUEZ ESTRADA JUAN ANTONIO HERRERA GONZALEZ PORFIRIO GUTIERREZ MARTINEZ (2022, [Artículo])

"Blueberry (Vaccinium corymbosum L.) is a crop with great potential for exportation and is very important for its antioxidant properties. However, this fruit is susceptible to different factors of deterioration and attack by pathogens. Botrytis cinerea is the main cause of post-harvest losses in this crop. Antagonistic yeasts from the Debaryomyces hansenii species, which is of marine origin, have been proposed as an alternative method for fungal control. For this reason, this study evaluated the in vitro and in vivo antagonistic capacity of the yeast against B. cinerea. The in vitro growth of the fungus was inhibited by 90% and germination was reduced by 100%, and through the production of volatile organic compounds, the growth of the pathogen was inhibited by 32.5%. Photographic evidence by electron microscopy revealed the effects caused by D. hansenii on B. cinerea. The incidence study showed a 50% reduction in the incidence of the disease caused by B. cinerea in blueberries, while quality parameters—such as soluble solids, titratable acidity, and pH—presented stable values, delaying the maturation process of the fruits. Likewise, the rate of reduction in firmness and physiological weight loss was lower, and the blueberries preserved their quality for a longer time."

Debaryomyces hansenii, blueberry, gray mold, postharvest quality CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS FITOPATOLOGÍA FITOPATOLOGÍA FITOPATOLOGÍA

Utilización de aguajes por el borrego cimarrón (Ovis canadensis cremnobates) y análisis de calidad del agua en Sierra Santa Isabel, Baja California, México

Watering sites use by bighorn sheep (Ovis canadensis cremnobates) and water quality analysis in Sierra Santa Isabel, Baja California, Mexico

Jonathan Gabriel Escobar Flores SERGIO ALVAREZ CARDENAS Sara Cecilia Díaz Castro Aradit Castellanos Vera Jorge Torres Rodriguez MARIANA DELGADO FERNANDEZ (2016, [Artículo])

"Se analizó la utilización de aguajes por el borrego cimarrón en la Sierra Santa Isabel, Baja California, México durante la temporada de sequía de 2011 y 2013 y el periodo de lluvias e inicio de la temporada de sequía del 2015. Asimismo, se estudió la calidad del agua, con base en siete parámetros fisicoquímicos. Se obtuvieron 260 registros fotográficos de borregos cimarrones, donde hembras, añeros y corderos representaron el 73%. En el periodo de lluvias, en dos de los aguajes se obtuvieron valores de conductividad de 1.31 µS/cm2 y 1.92 µS/cm2, y de sólidos disueltos totales de l0.65 ppt y 0.95 ppt, indicando un bajo contenido de sales en el agua. Los valores de oxígeno disuelto mayores a 6.4 ppm, dureza del agua menor a 100 ppm y PH entre 6.5 y 8.5, sugieren que el agua tiene condiciones óptimas para ser bebida por los borregos cimarrones. Los aguajes con mayor utilización por los borregos fueron El Zamora (n = 120) y El Cordero (n = 67), donde se registraron las mejores condiciones de calidad de agua en este estudio. El mayor registro de hembras y añeros, asociado a condiciones óptimas de calidad del agua, confirman la importancia de los aguajes para la crianza y reclutamiento del borrego cimarrón."

"Water used by bighorn sheep during the 2011 and 2013 dry seasons and the rainy season and drought of 2015 in the Sierra Santa Isabel of the State of Baja California, Mexico was analyzed for seven physicochemical parameters. At four watering sites, 260 photographs of sheep were obtained. Females, yearlings, and lambs accounted for 73% of the photographs. In the rainy season at two watering sites, conductivity was 1.31 µS/cm2 and 1.92 µS/cm2 and total dissolved solids was 0.65 and 0.95 ppt, indicating low salt content and safe for bighorn sheep. The watering sites with greater use by bighorn sheep were El Zamora (n = 120) and El Cordero (n = 67), which also had the best water quality. The frequent use by females and yearlings of the two sites with optimal water quality support the belief that watering sites for lambing and recruitment of bighorn sheep is important."

Baja California, borrego cimarrón, calidad del agua, cámaras trampa. Baja California, bighorn sheep, water quality, camera traps. BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) MAMÍFEROS MAMÍFEROS

Diseño de una red de dispositivos inalámbricos para monitorear la calidad del aire en interiores

FRIDA JENNY DE LA ROSA ANDRADE (2023, [Tesis de maestría])

No cabe duda de que la contaminación ambiental siempre a existido, y es una consecuencia

producida por las diferentes actividades que el ser humano ha realizado a lo largo de su

desarrollo y evolución tecnológica, por lo que conlleva a muchas repercusiones en la

integridad física del ambiente. Las actividades de desarrollo, como la construcción, el

transporte y la fabricación, no solo agotan los recursos naturales, sino que también producen

una gran cantidad de desechos que conducen a la contaminación del aire, el agua, el suelo y

los océanos, dando pie a los problemas más preocupantes del ser humano, tal es el caso del

calentamiento global, las lluvias acidas. Hoy en día la contaminación del aire se considera

un tema de gran importancia puesto que, es uno de los principales problemas en las zonas

más urbanizadas del mundo, y se encuentra presente tanto en los países desarrollados como

en los no desarrollados, por ello surge la necesidad de conocer que tan contaminado se

encuentra el aire que se respira.

El estándar de calidad del aire es una táctica para establecer las condiciones del aire desde un

grado de pureza, hasta una calidad critica perjudicial para el deterioro de la salud humana,

haciendo referencia a la cantidad de contaminación presente en el aire, definiéndola ya sea

de alta calidad con un nivel bajo de contaminación o una mala calidad con un nivel elevado

de concentración de contaminación en el aire.

En este proyecto se diseñará una Red de dispositivos inalámbricos para el análisis y

monitoreo de la calidad del aire en interiores, con la finalidad de fungir como un medidor de

contaminación que le permita a las personas darse cuenta de que tan contaminados están sus

hogares. Por tal motivo en el desarrollo de este proyecto se hará uso de un microcontrolador

Arduino IDE, un Node-red y un phpMyadmin para el análisis y monotoreo constante de

diversos gases como CO, CO2, metano, nitrógeno y O2. Cabe mencionar que este escrito se

ha dividido en 4 capítulos en los cuales se explica detalladamente todos y cada uno de los

procesos llevado a cabo para la elaboración y el desarrollo de este proyecto.

There is no doubt that environmental pollution has always existed, and is a consequence

produced by the different activities that human beings have carried out throughout their

development and technological evolution, which leads to many repercussions on the physical

integrity of the environment. Development activities such as construction, transportation and

manufacturing not only deplete natural resources but also produce a large amount of waste

leading to pollution of air, water, soil and oceans, giving rise to to the most worrying problems

of human beings, such as global warming and acid rain. Nowadays, air pollution is considered

an issue of great importance since it is one of the main problems in the most urbanized areas

of the world, and is present in both developed and undeveloped countries, which is why the

need to know how contaminated the air you breathe is.

The air quality standard is a tactic to establish air conditions from a degree of purity to a

critical quality harmful to the deterioration of human health, referring to the amount of

pollution present in the air, defining it either high quality with a low level of contamination

or poor quality with a high level of concentration of contamination in the air.

In this project, a network of wireless devices will be designed for the analysis and monitoring

of indoor air quality, with the purpose of serving as a pollution meter that allows people to

realize how polluted their homes are. For this reason, in the development of this project, an

Arduino IDE microcontroller, a Node-red and a phpMyadmin will be used for the analysis

and constant monitoring of various gases such as CO, CO2, methane, nitrogen and O2. It is

worth mentioning that this writing has been divided into 4 chapters in which each and every

one of the processes carried out for the preparation and development of this project is

explained in detail.

BIOLOGÍA Y QUÍMICA QUÍMICA Red de dispositivos inalámbricos, análisis monitoreo, calidad, riesgo, contaminación. Network of wireless devices, monitoring analysis, quality, risk, contamination.

Effect of Nitrogen, Phosphorus and Potassium on regional organic substrates in Agave salmiana production in Huichapan, Hidalgo, Mexico

EMILIO RAYMUNDO MORALES MALDONADO MONICA GUTIERREZ ROJAS RAMON JAIME HOLGUIN PEÑA Daniel Ruiz-Juárez Jorge Luis Vega Chávez Ana Cristina Reyes Godoy (2022, [Artículo])

"Mexico has 159 species of Agave spp. In the agri-food industry stand out are Agave tequilana, A. angustifolia, and A. salmiana. A limitation to producing maguey seedlings is the low availability of organic substrates that favor plant adaptation in the field. The objective was to evaluate the effect of nitrogen (N), phosphorus (P) and potassium (K) found in substrates in response to vegetative and root growth of A. salmiana in agricultural areas of Huichapan, Hidalgo, Mexico. The treatment consisted of earthworm humus (EH) and leaf compost (LC) substrates with materials from the region with different percentages of EH (100, 75, 50%), LC (5, 10%), and sand (20, 40%). The treatments were applied with 14 random replications in two phases in seeds and 40-day-seedlings. The variables evaluated were NPK amount and pH in substrates. The physiological variables measured were plant height, leaf number, stem diameter, root length, and volume. Significant differences (P≤0.05) were observed in seedling physiology due to the effect of the treatment. The best agronomic responses (plant growth and root length/weight) of Agave seedlings were T5 (75% earthworm humus + 20% sand + 5% leaf-soil) and T6 (50% earthworm humus + 40% sand + 10% leaf-soil); in both treatments, the NPK percentages were different from the control (Haplic Phaeozem soil) group. The final concentration of NPK in T6 was N = 0.04%, P = 398.13 mg Kg-1 and K = 11.88 meq 100g-1 . The results infer that NPK availability in soil and progressive acidification (initial pH = 8.6, final pH = 7.4) of the substrate can favorably influence the plant response. The interactions between NPK availability in the substrate and their use for a better response in maguey seedling adaptability open up new lines of research on the productive systems in the región of Huichapan, Hidalgo, Mexico."

maguey, nutritional quality, plant physiology, productive soils, seedling BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) FERTILIDAD DEL SUELO FERTILIDAD DEL SUELO

Aplicación de 1-MCP en diferentes ecotipos de ciruela mexicana (Spondias purpurea L.) de México

MARÍA GORETTI TRANSITO DAMASO (2023, [Tesis de maestría])

La ciruela mexicana es un frutal nativo de México, se distribuye en la vertiente del

Pacífico, centro de Veracruz y Península de Yucatán. El árbol de ciruela mexicana

produce frutos de diferentes tamaños, colores y sabores, existe una gran diversidad

que se aprecia tanto en los meses de marzo a junio, como de septiembre a noviembre.

El principal uso de la fruta es en fresco como fruta de temporada, la vida útil de la

ciruela de estación seca no es mayor a 5 d, por lo cual es un frutal que se considera

importante de manera local. Actualmente poco se han desarrollado y evaluado

tecnologías para incrementar la vida útil de este producto hortícola, por lo que en el

presente trabajo se evaluó la respuesta de cinco ecotipos de ciruela mexicana a la

aplicación de 1-metilciclopropeno (1-MCP), con la finalidad de proponerlo para el

desarrollo del manejo poscosecha adecuado de esta fruta. Durante abril a septiembre

de 2022 se cosecharon frutos de ciruela mexicana procedentes de Guerrero y Morelos.

Los frutos se cosecharon en etapa ½ verde. Los frutos fueron transportados al

Laboratorio de Producción Agrícola de la Facultad de Ciencias Agropecuarias en la

Universidad Autónoma del Estado de Morelos, donde se lavaron y se dejaron secar al

ambiente. Posteriormente se colocaron en cajas de plástico herméticas durante 12 h

y se aplicó 0, 500 y 1000 nL L-1 de 1-MCP, se evaluaron a temperatura ambiente (24.9

± 1 °C; 55.1 ± 6 % HR) y después de 5, 10 y 15 d en almacenamiento a 12 °C. Se

evaluaron los cambios fisicoquímicos y fisiológicos de cada ecotipo. La aplicación de

1-MCP, independiente del tiempo de almacenamiento inhibió y retrasó la velocidad de

respiración y producción de etileno, mantuvo la firmeza y retrasó la pigmentación

característica de cada ecotipo, con poca acción en la concentración de sólidos solubles

totales y acidez titulable, sin efecto claro en compuestos fenólicos, flavonoides y

actividad antioxidante, y sin ningún efecto en la pérdida de masa. El efecto del 1-MCP

permite conservar la fruta a temperatura ambiente hasta 6 u 8 d; la refrigeración a 12

°C potencia la acción del 1-MCP permitiendo conservar hasta 9 a 20 d después de

salir de almacenamiento.

The Mexican plum is a fruit native to Mexico, it is distributed on the Pacific slope, central

Veracruz and Yucatan Peninsula. The Mexican plum tree produces fruits of different

sizes, colors and flavors, there is a great diversity that is appreciated both in the months

of March to June, and from September to November. The main use of the fruit is fresh

as a seasonal fruit, the shelf life of the dry season plum is not more than 5 d, so it is a

fruit tree that is considered important locally. Currently, little technologies have been

developed and evaluated to increase the shelf life of this horticultural product, so in this

work the response of five ecotypes of Mexican plum to the application of 1-

methylcyclopropene (1-MCP) was evaluated, in order to propose it for the development

of adequate postharvest management of this fruit. During April to September 2022,

Mexican plum fruits were harvested from Guerrero and Morelos. The fruits were

harvested in stage 1/2 green. The fruits were transported to the Agricultural Production

Laboratory of the Faculty of Agricultural Sciences at the Autonomous University of the

State of Morelos, where they were washed and left to dry in the environment.

Subsequently, they were placed in airtight plastic boxes for 12 h and 0, 500 and 1000

nL L-1 of 1-MCP were applied, evaluated at room temperature (24.9 ± 1.1 °C; 55.1 ±

6.2 % RH) and after 5, 10 and 15 d in storage at 12 °C. The physicochemical and

physiological changes of each ecotype were evaluated. The application of 1-MCP,

independent of storage time inhibited and delayed the rate of respiration and production

of ethylene, maintained the firmness and delayed the pigmentation characteristic of

each ecotype, with little action on the concentration of total soluble solids and titratable

acidity, with no clear effect on phenolic compounds, flavonoids and antioxidant activity,

and without any effect on mass loss. The effect of 1-MCP allows the fruit to be

preserved at room temperature up to 6 or 8 d; cooling at 12 °C enhances the action of

1-MCP allowing to preserve up to 9 to 20 d after leaving storage

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS Ciruela mexicana, 1-metilciclopropeno, almacenamiento, refrigeración, calidad, poscosecha Mexican plum, 1-methylcyclopropene, storage, refrigeration, quality, postharvest.

Aproximación de señales acústicas a través de funciones polinomiales

Approximation of acoustic signals through polynomial functions

Andrea Cruz Rojas (2023, [Tesis de maestría])

Las señales acústicas presentan diversas características, como la frecuencia, amplitud y duración. Existen varias formas de representar una señal acústica, siendo la representación en el dominio del tiempo la más común. Esta representación permite visualizar la variación de la amplitud a lo largo del tiempo, analizar la duración, la forma de onda y los cambios rápidos o lentos en la amplitud. Sin embargo, las señales acústicas pueden contener un gran número de elementos, lo que resulta en archivos digitales de gran tamaño que dificultan su envío y almacenamiento. En este trabajo, se llevó a cabo un estudio de aproximación de señales acústicas utilizando diversas funciones polinomiales, como las funciones Zernike, Bessel y Jinc para reducir la cantidad de datos necesarios para representar la señal acústica, lo que simplifica la manipulación de dichos datos. El objetivo es identificar qué polinomio y cuántos coeficientes ofrecen un mejor rendimiento, es decir, una mejor señal acústica. Este estudio se basa en una evaluación objetiva y subjetiva de la reconstrucción de las señales acústicas, lo cual, hasta donde tenemos conocimiento, no se ha estudiado utilizando ambas metodologías en conjunto.

Acoustic signals have various characteristics, such as frequency, amplitude and duration. There are several ways to represent an acoustic signal, with time domain representation being the most common. This representation allows you to visualize the variation of the amplitude over time, analyze the duration, the waveform and the fast or slow changes in the amplitude. However, acoustic signals can contain a large number of elements, resulting in large digital files that make them difficult to send and store. In this work, an approximation study of acoustic signals was carried out using various polynomial functions, such as the Zernike, Bessel and Jinc functions to reduce the amount of data necessary to represent the acoustic signal, which simplifies the manipulation of said data. The objective is to identify which polynomial and how many coefficients offer better performance, that is, a better acoustic signal. This study is based on an objective and subjective evaluation of the reconstruction of acoustic signals, which, to the best of our knowledge, has not been studied using both methodologies together.

Calidad de audio, Compresión de señal acústica, Polinomios ortogonales, Pruebas objetivas y subjetivas. Audio quality, Acoustic signal compression, Orthogonal polynomials, Objective and Subjective Tests INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LAS TELECOMUNICACIONES ELECTROACÚSTICA ELECTROACÚSTICA