University of Navojoa

Nanocrystalline diamond (NCD) films were synthesized by microwave plasma chemical vapor deposition (MPCVD) from a CH4/Ar mixture on seedless p-type Si(111) substrates at 100–400 °C. Crystallinity was evaluated by X-ray diffraction (Cu Kα); bonding by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS); morphology and thickness by scanning electron microscopy (SEM); defect states by thermoluminescence (TL). SEM shows continuous films with uniform thickness. XRD displays a broad (111) reflection near 2θ = 44°. Raman and XPS reveal temperature-dependent bonding: between 300 and 400 °C, the sp3 fraction increases relative to sp2. TL glow curves show peaks at 157 °C and 270 °C, indicating electron-trap centers. These results demonstrate hydrogen-free and seedless NCD growth at low substrate temperatures, supporting potential electronic and dosimetry applications requiring a low thermal load.

The addition of silicon dioxide (SiO2) nanoparticles in concentrations of 1, 3, and 5% to type 1 Portland cement significantly increases its compressive strength properties. This increase in strength is the SiO2 nanoparticles fill pores in the concrete, act as nucleating agents for cement hydration, and improve the adhesion between cement and aggregates, which represents a great benefit to civil works.

En jitomate, el género Pythium puede causar pérdidas económicas hasta del 50%. Acibenzolar-S-metil es un inductor de la defensa de las plantas, que ha mostrado efectividad contra enfermedades causas por hongos, virus y bacterias. Los objetivos de este estudio fueron determinar el efecto in vitro del Acibenzolar-S-metil en el crecimiento micelial y en la severidad del ahogamiento de plántulas de jitomate causado por Pythium sp. El efecto in vitro se determinó en medio de cultivo V8, mientras que, la severidad del ahogamiento se determinó en plántulas con dos hojas verdaderas. El Acibenzolar-S-metil se aplicó vía riego a concentraciones de 10, 15, 20, 30 y 40 mg L-1, tres días antes de la inoculación de las plántulas con el oomiceto. La severidad por Pythium se evaluó ocho días después de la inoculación del patógeno. El Acibenzolar-S-metil no afectó el crecimiento micelial del oomiceto en condiciones in vitro. En plántula, la dosis de 15 mg L-1 del producto inductor redujo significativamente el daño causado por el oomiceto, en comparación con el tratamiento testigo y el tratamiento con el fungicida. Estos resultados sugieren que el Acibenzolar-S-metil podría representar una opción más para el manejo del ahogamiento de plántulas de jitomate causado por Pythium sp.

Shear walls, integrated into conventional reinforced concrete (RC) moment-resisting frame systems (RC frame–shear wall building), have proven to be effective in improving the structural performance and reliability of buildings; however, the seismic behavior of the building depends directly on the location of these elements. For this reason, this paper evaluates the structural reliability of ten medium-rise RC buildings designed based on the Mexico City Building Code, considering different shear wall configurations. With the aim to estimate and compare the seismic reliability, the buildings are modeled as complex 3D structures via the OpenSees 3.5 software, which are subjected to different ground motion records representative of the soft soil of Mexico City scaled at different intensity values in order to compute incremental dynamic analysis (IDA). Furthermore, the parameter used to estimate the reliability is the maximum interstory drift (MID), which is obtained from the incremental dynamic analysis in order to assess the structural fragility curves. Finally, the structural reliability estimation is computed via probabilistic models by combining the fragility and seismic hazard curves. It is concluded from the results that the structural reliability is maximized when shear walls are symmetrically distributed. On the other hand, the configuration with walls concentrated in the center of the building tends to oversize the frames to reach a reliability level comparable to that of symmetrical arrangements.

Objetivo: determinar el contenido total de azúcar de caña en diversas bebidas no alcohólicas elaboradas artesanalmente, en respuesta a la creciente prevalencia de obesidad en México, sugiriendo su posible papel como factor de riesgo obesogénico asociado a la alimentación. Metodología: diseño no experimental, cuantitativo, descriptivo y transversal de una población de 28 muestras de aguas frescas elaboradas artesanalmente a partir de concentrados industrializados. Las muestras, se obtuvieron de expendios públicos que incluyeron taquerías, refresquerías y paleterías, ubicadas en la zona centro de Navojoa, Sonora, México. La recolección de las muestras se realizó en el verano 2023. Se midieron los grados Brix para determinar la 1 Documento concentración de sacarosa. Las variedades de sabores responden a los comúnmente vendidos y fueron: piña colada (5 muestras), fresa (3 muestras), limón (10 muestras), jamaica (4 muestras), horchata (3 muestras) y cebada (3 muestras). Resultados: Los resultados revelaron un rango de concentración de sacarosa entre 72 g a 274 g por cada 1000 ml de bebida. Se obtuvo una media aritmética de 144.393 g/L y desviación estándar de 4.2641. Se realizó la prueba de normalidad para datos de Shapiro-Wilk con un valor de significancia de 0.120. Conclusión: Todas las muestras superaron la recomendación de consumo de sacarosa hecha por la Organización Mundial de la Salud, establecida en 50 g/día. Aunque los resultados se expresan en términos de un litro de bebida, es relevante señalar que, durante la temporada cálida, el consumo puede ser mayor a un litro. Dada la elevada concentración de sacarosa presente en las bebidas artesanales, el consumo de estos productos podría considerarse un factor de riesgo para el desarrollo de obesidad y otras enfermedades asociadas.

Fernanda S. ZAVALA-IBARRA, Aldo A. ARVIZU-FLORES, Oliviert MARTNEZ-CRUZ, Pablo S. OSUNA-AMARILLAS, Jos L. CRDENAS-LPEZ, Carmen L. DEL-TORO-SNCHEZ, Carlos R. GONZLEZ-RUIZ, Jos A. TAPIA-HERNNDEZ, Rey D. ITURRALDE-GARCA, Francisco J. CINCO-MOROYOQUI

Fish represent one of the most perishable food groups. Therefore, it is important to find viable alternatives that contribute to the preservation of quality and increase the shelf life of fishery products, and one alternative is to use natural extracts with antimicrobial activity. The objective of this study was to determine the effect of a natural extract prepared with garlic (NGE) on the quality and shelf life of tilapia fillets stored on ice for 18 days. For this purpose, NGE was prepared by homogenizing peeled garlic cloves with distilled water, which were then centrifuged to obtain the extract (NGE); then, the fish fillets were immersed in the extract and were coated in NGE. The fillets with NGE were packed in high-density polyethylene bags and stored in crushed ice for 18 days. The adenosine 5′-triphosphate (ATP) and degradation products, K-value, color, texture, water holding capacity, pH, total mesophilic count, and total volatile bases (TVB-N) were monitored during storage. The ATP content, K-value, pH, total microbial count, and TVB-N changed with respect to ice storage time, and the results between fillets with NGE and control fillets differed. In conclusion, the application of NGE increased the shelf life of fillets stored on ice by 6 days, obtaining a shelf life of 18 days on ice, which shows its potential to improve the utilization of the species.

In Economic and Administrative Sciences, factor analysis models are essential due to their explanatory capacity of institutional responses to a risk event. The objective of this article is to contrast a model that explains the emergence of corporate governance dimensions in the face of the pandemic. An exploratory study was carried out based on a systematic review of the literature, from 2019 to 2022, considering the search by keywords in Google Scholar and Microsoft Academic, as well as the validity by judges and the survey of 100 students from a public university in the center of Mexico. The results show that corporate identity explains the university's response to the pandemic. In relation to the state of the art, the scope and limits of the model are discussed in relation to other proposals. JEL Codes: I12 Received: 09/08/2021.. Accepted: 16/06/2022. Published: 21/03/2023.