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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

Classification of Cucumber Leaves Based on Nitrogen Content Using the Hyperspectral Imaging Technique and Majority Voting.

Sajad Sabzi Razieh Pourdarbani Mohammad Hossein Rohban Alejandro Fuentes_Penna José Luis Hernández-Hernández Mario Hernández Hernández (2021, [Artículo])

Improper usage of nitrogen in cucumber cultivation causes nitrate accumulation in the fruit and results in food poisoning in humans; therefore, mandatory evaluation of food products becomes inevitable. Hyperspectral imaging has a very good ability to evaluate the quality of fruits and vegetables in a non-destructive manner. The goal of the present paper was to identify excess nitrogen in cucumber plants. To obtain a reliable result, the majority voting method was used, which takes into account the unanimity of five classifiers, namely, the hybrid artificial neural network¿imperialism competitive algorithm (ANN-ICA), the hybrid artificial neural network¿harmonic search (ANN-HS) algorithm, linear discrimination analysis (LDA), the radial basis function network (RBF), and the Knearest- neighborhood (KNN). The wavelengths of 723, 781, and 901 nm were determined as optimal wavelengths using the hybrid artificial neural network¿biogeography-based optimization (ANNBBO) algorithm, and the performance of classifiers was investigated using the optimal spectrum. The results of a t-test showed that there was no significant difference in the precision of the algorithm when using the optimal wavelengths and wavelengths of the whole range. The correct classification rate of the classifiers ANN-ICA, ANN-HS, LDA, RBF, and KNN were 96.14%, 96.11%, 95.73%, 64.03%, and 95.24%, respectively. The correct classification rate of majority voting (MV) was 95.55% for test data in 200 iterations, which indicates the system was successful in distinguishing nitrogen-rich leaves from leaves with a standard content of nitrogen.

artificial neural network cucumber hyperspectral imaging majority voting nitrogen INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ALIMENTOS

Comparison of Different Classifiers and the Majority Voting Rule for the Detection of Plum Fruits in Garden Conditions.

Razieh Pourdarbani Sajad Sabzi Mario Hernández Hernández José Luis Hernández-Hernández Ginés García_Mateos Davood Kalantari José Miguel Molina Martínez (2019, [Artículo])

Color segmentation is one of the most thoroughly studied problems in agricultural applications of remote image capture systems, since it is the key step in several different tasks, such as crop harvesting, site specific spraying, and targeted disease control under natural light. This paper studies and compares five methods to segment plum fruit images under ambient conditions at 12 different light intensities, and an ensemble method combining them. In these methods, several color features in different color spaces are first extracted for each pixel, and then the most e

ective features are selected using a hybrid approach of artificial neural networks and the cultural algorithm (ANN-CA). The features selected among the 38 defined channels were the b* channel of L*a*b*, and the color purity index, C*, from L*C*h. Next, fruit/background segmentation is performed using five classifiers: artificial neural network-imperialist competitive algorithm (ANN-ICA); hybrid artificial neural network-harmony search (ANN-HS); support vector machines (SVM); k nearest neighbors (kNN); and linear discriminant analysis (LDA). In the ensemble method, the final class for each pixel is determined using the majority voting method. The experiments showed that the correct classification rate for the majority voting method excluding LDA was 98.59%, outperforming the results of the constituent methods.

remote sensing in agriculture artificial neural network hybridization environmental conditions majority voting plum segmentation INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ALIMENTOS

A Novel Technique for Classifying Bird Damage to Rapeseed Plants Based on a Deep Learning Algorithm.

Ali Mirzazadeh Afshin Azizi Yousef Abbaspour_Gilandeh José Luis Hernández-Hernández Mario Hernández Hernández Iván Gallardo Bernal (2021, [Artículo])

Estimation of crop damage plays a vital role in the management of fields in the agricultura sector. An accurate measure of it provides key guidance to support agricultural decision-making systems. The objective of the study was to propose a novel technique for classifying damaged crops based on a state-of-the-art deep learning algorithm. To this end, a dataset of rapeseed field images was gathered from the field after birds¿ attacks. The dataset consisted of three classes including undamaged, partially damaged, and fully damaged crops. Vgg16 and Res-Net50 as pre-trained deep convolutional neural networks were used to classify these classes. The overall classification accuracy reached 93.7% and 98.2% for the Vgg16 and the ResNet50 algorithms, respectively. The results indicated that a deep neural network has a high ability in distinguishing and categorizing different image-based datasets of rapeseed. The findings also revealed a great potential of Deep learning-based models to classify other damaged crops.

rapeseed classification damaged crops deep neural networks INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ALIMENTOS

In vitro Digestibility of Yarrowia lipolytica Yeast and Growth Performance in Whiteleg Shrimp Litopenaeus vannamei

ANA RUTH ALVAREZ SANCHEZ CLAUDIO HUMBERTO MEJIA RUIZ Héctor Gerardo Nolasco Soria Alberto Peña Rodríguez (2018, [Artículo])

"Marine yeasts used in aquaculture disease control can also be an important protein source for improving feeding and nutrition of crustaceans. Yarrowia lipolyticca has been studied for its capacity to secrete heterologous proteins and high content of unsaturated fatty acids, beta-glucan, and mannane polymers in the cell wall. We measured in vitro digestibility of Y. lipolyticca by whiteleg shrimp Litopenaeus vannamei digestive enzymes, and an in vivo assay of Y. lipolytica in feed onwhiteleg shrimp growth. We found that digestive gland enzymes of shrimp digest Y. lipolytica, based on reduced optical density of a yeast suspension. Digestion was –0.00236 ± 0.00010 OD U min–1 for intact cells and –0.00325 ± 0.00010 OD U min–1 for lysed cells. Release of reducing sugars in intact cells (5.3940 ± 0.1713 μmol h–1), and lysed cells (0.8396 ± 0.2251 μmol h–1) was measured. Digestive gland treatment significantly reduced cell viability (near 100%), relative to the control. Electron microscopy shows that the cell wall of Y. lipolytica exposed to the digestive gland enzymes was severely damaged. Shrimp diet containing Y. lipolytica resulted in significantly higher weight gain and specific growth rate of whiteleg shrimp."

Marine yeast, cell digestibility, cell viability, turbidimetry, reduced sugars BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOQUÍMICA BIOQUÍMICA DE ALIMENTOS BIOQUÍMICA DE ALIMENTOS

Las cáscaras de naranja: ¿Desechos de la agricultura o riqueza farmacéutica?

ROLFFY RUBEN ORTIZ ANDRADE JESUS ALFREDO ARAUJO LEON Gregoreo Centeno Hoil MICHELLE SANSORES CHUC (2023, [Artículo])

México se encuentra entre los diez primeros países con la mayor producción de cítricos, siendo Yucatán uno de los principales estados productores, en particular, de naranjas. Actualmente, la producción de cítricos se utiliza para la extracción de jugo para alimentos y bebidas. Sin embargo, las cáscaras de naranjas son desechadas o subutilizadas. En este ensayo abordamos una perspectiva del potencial médico y económico que existe en las cáscaras de naranja y que podrían ser una riqueza farmacéutica por su alto contenido de flavonoides, moléculas que han sido objeto de estudio para la prevénción de la diabetes, hipertensión y la obesidad.

CITRUS SINENSIS DIABETES HESPERIDINA HIPERTENSION NARINGENINA OBESIDAD BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) EXPLOTACIÓN DE LOS CULTIVOS EXPLOTACIÓN DE LOS CULTIVOS

Estudios florísticos locales ¿son importantes? La maravillosa y poco conocida flora de Susticacán, Zacatecas, México

Leopoldo Hurtado-Reveles MIREYA BURGOS HERNANDEZ (2023, [Artículo])

Enclavado en la Sierra de los Cardos, en una de las formaciones montañosas más importantes del estado de Zacatecas en México, se ubica el pequeño municipio de Susticacán, el menos poblado de esa entidad y reconocido por su belleza paisajística. A pesar de su superficie, recientes investigaciones demuestran el gran número de especies y endemismos con los que cuenta, constituyendo un área de resguardo de una importante riqueza vegetal. Esto enmarca la importancia de llevar a cabo estudios florísticos a nivel local que se traduzcan en buenas decisiones de manejo y conservación de las especies, en beneficio de los pobladores locales.

CONSERVACION ESPECIES ENDEMICAS ESTUDIOS FLORISTICO-TAXONOMICOS SIERRA DE LOS CARDOS SIERRA MADRE OCCIDENTAL BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Distribución de la variación genética de insectos asociados a Hesperoyucca whipplei en la península de Baja California

Distribution of genetic variation of insects associated with Hesperoyucca whipplei in the Baja California peninsula

Roberto Suárez Hernández (2024, [Tesis de maestría])

El tipo de interacción ecológica obligada entre plantas hospederas y sus insectos asociados ha demostrado tener un impacto en la diversidad genética de las especies involucradas. La yuca de chaparral, Hesperoyucca whipplei, presenta una relación de mutualismo obligado con la polilla polinizadora Tegeticula maculata, y de comensalismo obligado con la polilla Prodoxus marginatus. Ambos insectos depositan sus huevos en estructuras de la flor y se alimentan del fruto en desarrollo. Con el fin de determinar el efecto de la interacción ecológica sobre la diversidad genética de los insectos, en este estudio se evaluó el nivel de variación y estructura genética de ambas polillas a lo largo de la península de Baja California. Se amplificó el gen mitocondrial COI en 86 individuos de T. maculata y 120 individuos de P. marginatus. La diversidad haplotípica fue menor en T. maculata (Hd = 0.601) en comparación con P. marginatus (Hd = 0.966) mientras que la diversidad nucleotídica fue baja en ambas especies (Pi= 0.0018 y 0.007 respectivamente). Las redes haplotípicas, el AMOVA, la prueba mismatch y los valores D de Tajima en T. maculata indican un patrón de expansión poblacional, mientras que en P. marginatus indican una estabilidad demográfica. Estos hallazgos sustentan que el mutualismo obligado entre H. whipplei y T. maculata, en contraste con el comensalimo obligado con P. marginatus, tiene un impacto directo en el nivel de la diversidad genética de las polillas, más que en su estructura a lo largo del área de distribución.

The type of obligate ecological interaction between host plants and their associated insects has been showing to have an impact on the genetic diversity of the species involved. The chaparral yuca (Hesperoyucca whipplei) presents a relationship of obligate mutualism with the pollinating moth Tegeticula maculata, and obligate commensalism with the moth Prodoxus marginatus. Both insects deposit their eggs in flower structures and feed on the developing fruit. To determine the effect of ecological interactions on insects’ genetic diversity, this study evaluated the level of variation and genetic structure of both moths throughout the Baja California peninsula. The mitochondrial COI gene was amplified in 86 individuals of T. maculata and 120 individuals of P. marginatus. Haplotypic diversity was lower in T. maculata (Hd = 0.601) compared to P. marginatus (Hd = 0.966) while nucleotide diversity was low in both species (pi = .0018 and 0.007 respectively). Haplotype networks, AMOVA, mismatch test and Tajima’s D values in T. maculata indicate a pattern of population expansion, whereas in P. marginatus they indicate demographic stability. These findings support that obligate mutualism between H. whipplei and T. maculata, in contrast, to obligate commensalism with P. marginatus, has a direct impact on the level of genetic diversity of the moths, rather than on their structure across the distribution.

mutualismo, comensalismo, filogeografía comparativa, polillas mutualism, commensalism, comparative phylogeography, moth BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA DE INSECTOS (ENTOMOLOGÍA) ECOLOGÍA DE LOS INSECTOS ECOLOGÍA DE LOS INSECTOS

REAL TIME EMBBEDED RGB-D SLAM USING CNNS FOR DEPTH ESTIMATION AND FEATURE EXTRACTION

Marcos Renato Rocha Hernández (2023, [Tesis de maestría])

"A robust and efficient Simultaneous Localization and Mapping (SLAM) system is essential for intelligent mobile robots to work in unknown environments. For visual SLAM algorithms, though the theoretical framework has been well established for most aspects, feature extraction and association is still empirically de signed in most cases, and can be vulnerable in complex environments. Also, most of the most robust SLAM algorithms rely on special devices like a stereo camera or depth sensors, which can be expensive and give more complexity to the system, that is why monocular depth estimation is an essential task in the computer vision community. This work shows that feature extraction and depth estimation using a monocular camera with deep convolutional neural networks (CNNs) can be incorporated into a modern SLAM framework. The proposed SLAM system utilizes two CNNs, one to detect keypoints in each im age frame, and to give not only keypoint descriptors, but also a global descriptor of the whole image and the second one to make depth estimations from a single image frame, all using only a monocular camera."

SLAM Inteligencia Artificial CNN Sistemas embebidos Redes neuronales Cámara monocular INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ORDENADORES INTELIGENCIA ARTIFICIAL INTELIGENCIA ARTIFICIAL

Tensile behavior of 3D printed polylactic acid (PLA) based composites reinforced with natural fiber

Eliana M Agaliotis BALTAZAR DAVID AKE CONCHA ALEJANDRO MAY PAT Juan Pablo Morales Arias Celina Bernal Alex Valadez González Pedro Jesús Herrera Franco Gwenaelle Proust JUAN FRANCISCO KOH DZUL José Gonzalo Carrillo Baeza Emmanuel Alejandro Flores Johnson (2022, [Artículo])

Natural fiber-reinforced composite (NFRC) filaments for 3D printing were fabricated using polylactic acid (PLA) reinforced with 1–5 wt% henequen flour comprising particles with sizes between 90–250 μm. The flour was obtained from natural henequen fibers. NFRCs and pristine PLA specimens were printed with a 0° raster angle for tension tests. The results showed that the NFRCs’ measured density, porosity, and degree of crystallinity increased with flour content. The tensile tests showed that the NFRC Young’s modulus was lower than that of the printed pristine PLA. For 1 wt% flour content, the NFRCs’ maximum stress and strain to failure were higher than those of the printed PLA, which was attributed to the henequen fibers acting as reinforcement and delaying crack growth. However, for 2 wt% and higher flour contents, the NFRCs’ maximum stress was lower than that of the printed PLA. Microscopic characterization after testing showed an increase in voids and defects, with the increase in flour content attributed to particle agglomeration. For 1 wt% flour content, the NFRCs were also printed with raster angles of ±45° and 90° for comparison; the highest tensile properties were obtained with a 0° raster angle. Finally, adding 3 wt% content of maleic anhydride to the NFRC with 1 wt% flour content slightly increased the maximum stress. The results presented herein warrant further research to fully understand the mechanical properties of printed NFRCs made of PLA reinforced with natural henequen fibers. © 2022 by the authors.

POLYLACTIC ACID (PLA) NATURAL FIBER HENEQUEN FIBER NATURAL FIBER REINFORCED COMPOSITE (NFRC) ADDITIVE MANUFACTURING 3D PRINTING MECHANICAL PROPERTY INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE MATERIALES PROPIEDADES DE LOS MATERIALES PROPIEDADES DE LOS MATERIALES