Durango Institute of Technology

The representation of Spanish-speaking students in STEM identity literature, particularly in physics identity, is conspicuously minimal. This study addresses this gap with a two-pronged approach. First, a physics identity instrument was adapted for Spanish-speaking STEM students to promote inclusivity in educational research. Data from 334 Mexican STEM students was collected and analysed for validation through factor analyses and Cronbach’s alpha, confirming the structural integrity and reliability of the adapted instrument. Second, the instrument was employed to examine the correlation between physics identity and academic performance in a separate dataset from 200 engineering students, using multivariate linear and logistic regressions. The findings underscore gender’s impact on physics course grades. Notably, variations in physics identity among engineering students indicated a potential link with their chosen field. Despite the importance of physics in engineering, physics identity was lower than expected, and performance in physics courses did not consistently correlate with a strong physics identity. However, the ‘interest in physics topics’ subconstruct did correlate with physics course grades. This research fills a critical void by providing an adapted instrument for assessing physics identity in Spanish-speaking students and underscores the need for pedagogical shifts to enhance physics identity and STEM outcomes for Latino students.

This study aimed to assess the impact of roasting degree on antioxidant and metabolic parameters in vitro and in vivo. In vitro, we evaluated radical scavenging, lipid peroxidation, and the activity of digestive enzymes (α-glucosidase, α-amylase, and lipase). In vivo, we first examined coffee's effect on carbohydrate and lipid absorption in healthy rats, followed by a chronic evaluation of metabolic disorders and antioxidant markers using a diet-induced obesity model. In vitro results revealed that increased roasting degree reduced the antioxidant capacity of coffee brews. All brews showed lower inhibition of α-glucosidase and α-amylase, and lipase inhibition compared to the positive control (acarbose or orlistat). In vivo, all roasting degrees consistently reduced postprandial glucose levels by 20%. Notably, coffee with a high roasting degree (HRD) decreased serum triglycerides (TG) by ∼44% after a lipid load, while other roasts did not. Chronic administration of unroasted (UN) or HRD coffee significantly reduced weight gain compared to the obese control (∼15% and ∼10%, respectively). Notably, all coffee samples improved lipid metabolism parameters. UN and HRD coffee significantly decreased adipocyte volume by 58% and 48%, respectively, compared to the obese control. Additionally, all groups exhibited less than 30% hepatic lipid droplets independent of roasting degree. HRD treatment notably increased liver catalase (CAT) activity and reduced lipid peroxidation in serum (∼90%), liver (∼59%), and adipose tissue (∼37%) compared to the obese control group. These findings suggest that HRD in coffee may confer certain biological advantages.

The viscoelastic behavior of food‐grade biopolymers during gelation has a complex frequency spectrum that is difficult to measure by commercial rheometers. Master curves built by time–temperature superposition (TTS) of data arising from small‐amplitude oscillatory flow (SAOS) or stress relaxation at a given reference temperature can provide the frequency span required to describe the frequency spectrum of highly complex systems such as hydrocolloids (e.g., κappa‐carrageenan). In this work, master curves using TTS were obtained for various concentrations (1%–4% w/w). For a given concentration, mechanical spectra were generated for various temperatures (5, 10, 25, 37, and 45°C) to obtain the master curves and shifting factors (aT, bT) using the WLF (Williams–Landel–Ferry) equation. In this context, a methodology is suggested to obtain a wide observation window to describe complex spectra from gelling systems employed in the chemical industry. Practical applications The rheological methods used in this work combined the enhancement of the frequency range from experimental stress relaxation and SAOS data with double superposition. These methods are already known, but the combination to achieve an ample frequency range of more than 8 decades represents a useful tool for industrial applications of gelling systems like food hydrocolloids (i.e., κappa‐carrageenan). It also helps to predict the viscoelastic behavior at temperatures and concentrations outside the usual range of rheometric measurements. It is further useful in the areas of equipment design and quality control for food products.

Hydrothermal liquefaction (HTL) is the thermochemical transformation of biomass in water at high temperatures and pressure into highly energetic bio-crude oil and biochar. This technology is regarded as an alternative or complement to biomass transformation bioprocesses. It is simple and fast, few variables are involved, and the produced phases are valuable for various applications. Still, many research gaps must be filled to conduct this technology to practical applications, including the energy efficiency and characterization of properties and products towards proper application selection, separation and utilization in refinery operations. This work evaluated on a 2² experimental design basis the effects of temperature (250 and 300 °C) and corn stover (CS) content (10 and 20 wt% total suspended solids, TSS) at autogenous pressure (4 and 9 MPa) and 15 min reaction time. Bio-crude and biochar yields, elemental composition, higher heating value (HHV), energy recovery (ER), and the composition of bio-crude oil and structural properties of biochar were determined. Results indicated that the CS content notably affected the total bio-crude yields; the best, 19.4%, corresponded to 10 wt% TSS. For biochar yields, up to 31.51%, both factors were significant. Analysis of bio-crude oil showed valuable functionalized phenol derivatives, ketones, and cycloalkenes of interest to chemical industries, pharmaceutical, and fuels. The best characteristics as fuel (elevated HHV, low O and S contents) were obtained at 300 °C, at 10 and 20 wt% TSS CS content for bio-crude (35.23 MJ/kg) and biochar (25.37 MJ/kg), respectively. Lastly, biochar with the highest pore volume and specific area, useful for adsorbent of pollutants, was obtained at 250 °C and 10 wt% TSS. In conclusion, using moderate energy-intensive operation conditions, CS HTL produced biochar suitable for its use as solid fuel, as an adsorbent for water treatment, or as supporting material and catalyst; bio-crude may be refinable into fuel or valuable derivatives. Graphical abstract

The mining and metallurgical industry represents one of the leading causes of environmental pollution. In this context, the optimization of mineral waste management and the efficient extraction of metals of interest becomes an imperative priority for a sustainable future. Microorganisms such as Acidithiobacillus thiooxidans have represented a sustainable and economical alternative in recent years due to their capacity for environmental remediation in bioleaching processes because of their sulfur-oxidizing capacity and sulfuric acid generation. However, its use has been limited due to the reluctance of mine operators because of the constant reproduction of the bacterial culture in suitable media and the care that this entails. In this work, the central objective was to evaluate the functional characteristics of A. thiooxidans, microencapsulated and stored at room temperature for three years in vacuum bags, using a spray drying process with gum arabic as a wall vector. Growth kinetics showed a survival of 80 ± 0.52% after this long period of storage. Also, a qualitative fluorescence technique with a 5-cyano-2-3 ditolyl tetrazolium (CTC) marker was used to determine the respiratory activity of the microorganisms as soon as it was resuspended. On the other hand, the consumption of resuspended sulfur was evaluated to corroborate the correct metabolic functioning of the bacteria, with results of up to 50% sulfur reduction in 16 days and sulfate generation of 513.85 ± 0.4387 ppm and 524.15 ± 0.567 ppm for microencapsulated and non-microencapsulated cultures, respectively. These results demonstrate the success after three years of the microencapsulation process and give guidelines for its possible application in the mining-metallurgical industry. Graphical abstract Microencapsulation process of A. thiooxidans using gum arabic as wall material. Its application may serve as an attractive alternative for the mining industry and as a tool to mitigate the environmental impact of such practices. Created with BioRender.com

This research analyzed the outcomes of an inquiry-based learning (IBL) activity presented to electronics engineering students to help them develop their abilities, propose new experiments, and construct their own knowledge. The IBL activity was led by a carbon nanotubes-based sensor prototype presentation where 39 engineering students were introduced to the operation of the prototype, followed by a discussion where the presenters highlighted possible applications of this type of prototype and a ten-minute questions session. At the end of the presentation, all participants answered a survey analyzing the impact of the IBL activity on their understanding of electronics engineering concepts and their motivation to design new experiments to explore and test their knowledge. The qualitative and quantitative data analysis showed that most of the participants were interested in the IBL activity, reporting that they would like to have more of this type of presentation in their engineering courses. Participants’ interest in the prototype presentation was reflected in their understanding of electronics engineering-related topics and their motivation to design new prototypes. They reported that they learned something new or developed a better understanding of topics they previously learned in their courses from the examples shown during the IBL activity. This research suggests that more IBL activities and partnerships with the industry should be included in electronics engineering courses aimed at developing students’ abilities to design and build technological applications.

An analysis and modeling of the linear viscoelastic behavior of maltenes (M) blended with styrene–butadiene–styrene block copolymer (SBS) are presented in this study. M were mixed with different amounts of SBS (Elastomer, E) (0.25–80 wt%) to investigate the effect of polymer concentration on linear viscoelastic response of the blends; storage and loss moduli were obtained from small amplitude oscillatory shear tests (SAOS). Time–temperature superposition master curves were analyzed by a Maxwell multi-modal model with up to nine relaxation times. Han, Cole–Cole and Van Gurp-Palmen diagrams were prepared from the rheological data. Two different responses were observed: At low E contents, a dispersed system rheological response was observed and verified by microscopy with elastomer as the dispersed phase and maltenes as the matrix, while at high E content the response was that of a co-continuous system. Mixtures with E > 2 wt% exhibited change in their thermomechanical properties with a phase inversion at E > 50 wt%. Furthermore, at low E concentration resins stabilize the dispersed phase by diminishing the magnitude of the viscoelastic moduli, conversely, at high E concentration a swelled polymer-rich phase creates a network that significantly influences of the viscoelastic properties.

Mathematics self-efficacy and mathematics anxiety can influence a student’s decision to pursue and complete an engineering major, and these influences can disproportionately affect female students. This research adapted two instruments to collect information about the mathematics self-efficacy and mathematics anxiety of first-year engineering students at a Mexican university. Descriptive statistics and k-means cluster analyses were used aiming to characterize engineering students based on their levels of mathematics self-efficacy and mathematics anxiety; and a MANOVA was used to test for sex-based differences. The results showed that engineering students are likely to have high levels of mathematics self-efficacy, and they also have high levels of mathematics anxiety. Male students reported higher mathematics self-efficacy and lower overall mathematics anxiety levels than female students, and mathematics test anxiety levels were higher than overall mathematics anxiety for both male and female students. Reliably characterizing engineering students’ levels of mathematics self-efficacy and anxiety can help educators better understand their students as they learn mathematics and develop learning environments that leverage students’ confidence in performing mathematic-related activities. This study highlights the need to identify ways to ameliorate engineering students’ feelings of mathematics test anxiety.

An analysis and modelling of the linear viscoelastic behavior of maltenes (M) blended with styrene-butadiene-styrene block copolymer (SBS) are presented in this study. M were mixed with different amounts of SBS (Elastomer, E) (0.25 to 80 wt.%) to investigate the effect of polymer concentration on linear viscoelastic response of the blends; storage and loss moduli were obtained from small amplitude oscillatory shear tests (SAOS). Time-temperature superposition master curves were analyzed by a Maxwell multimodal model with up to nine relaxation times. Han, Cole-Cole and Van Gurp-Palmen diagrams were prepared from the rheological data. Two different responses were observed: At low E contents, a dispersed system rheological response was observed and verified by microscopy with elastomer as the dispersed phase and maltenes as the matrix, while at high E content the response was that of a co-continuous system. Mixtures with E > 2 wt % exhibited change in their thermomechanical properties with a phase inversion at E > 50 wt. %. Furthermore, at low E concentration resins stabilize the dispersed phase by diminishing the magnitude of the viscoelastic moduli, conversely, at high E concentration a swelled polymer-rich phase creates a network that significantly influences of the viscoelastic properties.

Consumption of foods with fiber and compounds can promote gastrointestinal health and reduce obesity complications. Therefore, treatment with common bean leaves (BL) against obesity was evaluated in mice with a high-fat and high-fructose diet (HFFD) for 14 weeks. The bromatological and phytochemical characterization of BL were determined. Afterwards, the animals were supplemented with BL (10%) or a standard diet (SD) as a strategy to encourage a healthy diet for 12 additional weeks. Changes in body composition, lipid profile, and intestinal integrity were analyzed. The characterization of BL stood out for its content of 27.2% dietary fiber, total phenolics (475.04 mg/100 g), and saponins (2.2 mg/100 g). The visceral adipose tissue (VAT) decreased in the BL group by 52% compared to the HFFD group. Additionally, triglyceride levels were 23% lower in the BL consumption group compared to the HFFD group. The improvement in lipid profile was attributed to the 1.77-fold higher fecal lipid excretion in the BL consumption group compared to the HFFD group and the inhibition of pancreatic lipase by 29%. Furthermore, BL supplementation reduced the serum levels of IL-6 (4.4-fold) and FITC–dextran by 50% compared with those in the HFFD group. Metabolic endotoxemia was inhibited after BL supplementation (−33%) compared to the HFFD group. BL consumption as a treatment in obese mice reduces adipose tissue accumulation and improves the lipid profile. Furthermore, we report for the first time that BL consumption improves intestinal integrity.

Whey, a primary byproduct of cheese production, is rich in organic content, largely due to its lactose concentration (45–60 g/L). Cheese production yields three types of residues: sweet whey (SW), acid whey, and ricotta whey (RW). Each has unique physicochemical properties that present challenges for small to medium-sized enterprises because of the expensive treatment required. One solution to this problem is fermenting these substrates to produce value-added products. This study aimed to assess the fermentation of the three RW types using Kluyveromyces marxianus ITD00262 for isoamyl acetate production, a compound that gives a banana-like aroma. Several factors were analyzed: cell growth, pH changes, lactose content reduction, ethanol production, and isoamyl acetate formation. Cell growth was consistent across all whey types. As for pH, there was a drop during the initial 48 h to roughly 4.3, after which it rose to near 7. In acid whey, 50.95 g/L of ethanol was produced by the 120-h mark. The peak isoamyl acetate concentration was observed at 24 h, registering 160 mg/L in YPL medium, while SW peaked at 124 mg/L at 72 h. Lastly, the highest lactose consumption was seen in SW, approximately 76% at 24 h, surpassing that of acid and ricotta whey, which fluctuated between 56 and 58%. Graphical Abstract

Due to suitable bandgap and excellent stability, 3C-SiC is being investigated as one of the promising candidates for photoelectrochemical (PEC) water oxidation. However, the limited surface activity and short carrier...

This research aimed to compare the genetic profile by karyo- types of strains of K. marxianus from different regions in México. K. marxianus karyotypes were analyzed by pulsed-field gel elec- trophoresis (PFGE-CHEF). The Cluster analysis was calculated by clustering the Pearson´s correlations matrix using the UPGMA algorithm, and mathematical models were used to describe some parameters that could not be determined analytically. K. marxianus strains showed 17 different chromosomal patterns divided into two Clusters. Cluster I only include the reference strain K. marxianus (CBS397). However, obtaining some karyo- types showed similar fermentative behaviours, while others had different fermentative behaviours. Therefore, it has been possi- ble to differentiate a strain from different fermentation environ- ments. The strains isolated from mezcal do not show significant differences except the strain with karyotype XII therefore obtaining information on the relationship between genetic and fermentative behaviour is a tool for strain selection for different technological applications.

Endurance exercise promotes damage at the intestinal level and generates a variety of symptoms related to oxidative stress processes, inflammatory processes, microbiota dysbiosis, and intestinal barrier damage. This study evaluated the effects of quince (Cydonia oblonga Mill.) and probiotics of the genera Lactobacillus and Bifidobacterium on intestinal protection and exercise endurance in an animal swimming model. Phytochemical characterization of the quince fruit demonstrated a total dietary fiber concentration of 0.820 ± 0.70 g/100 g and a fiber-bound phenolic content of 30,218 ± 104 µg/g in the freeze-dried fruit. UPLC-PDA-ESI-QqQ analyses identified a high content of polyphenol, mainly flavanols, hydroxycinnamic acids, hydroxybenzoic acids, flavonols, and, to a lesser extent, dihydrochalcones. The animal model of swimming was performed using C57BL/6 mice. The histological results determined that the consumption of the synbiotic generated intestinal protection and increased antioxidant (catalase and glutathione peroxidase enzymes) and anti-inflammatory (TNF-α and IL-6 and increasing IL-10) activities. An immunohistochemical analysis indicated mitochondrial biogenesis (Tom2) at the muscular level related to the increased swimming performance. These effects correlated mainly with the polyphenol content of the fruit and the effect of the probiotics. Therefore, this combination of quince and probiotics could be an alternative for the generation of a synbiotic product that improves exercise endurance and reduces the effects generated by the practice of high performance sports.

This research involved conducting continuous adsorption experiments to assess fluoride elimination from drinking water achieved by utilizing biocomposites created from the peels of oranges and apples, which were impregnated with zirconium (Zr), to form BOP-Zr and BAP-Zr, respectively. The findings from the experimental data indicate that BOP-Zr and BAP-Zr are effective biosorbents with a solid ability to remove fluoride selectively. Additionally, these biosorbents were found to be stable, as they do not release Zr into the treated water. Notably, these environmentally friendly biosorbents are derived from renewable sources and enhance the value of waste materials. The study employed various empirical models, including Bohart-Adamas, Thomas, Yoon-Nelson, BDST, Clark, Yan, and Woolborska, to elucidate the mechanisms and crucial parameters involved in fluoride adsorption within packed bed columns. The Yan model demonstrated the highest correlation among these models, indicating a chemical adsorption process with kinetics following a pseudo-second-order pattern. BOP-Zr and BAP-Zr exhibited a maximum adsorption capacity of 59.3 and 47.5 mg/g, respectively, under a flow rate of 4 mL/min and an inlet fluoride concentration of 25 mg/L. The analysis of mass transfer coefficients revealed that the primary step governing the adsorption procedure was diffusion through pores. Consequently, the study conclusively establishes that BOP-Zr and BAP-Zr biocomposites, originating from lignocellulosic biomass remains, present a practical and competitive choice for eliminating fluoride from water. These materials surpass waste materials in performance and rival more expensive options in efficiency and performance.

Abordar el tema de la salud mental positiva en los docentes de una institución educativa de nivel superior antes y durante la pandemia de covid-19 ha sido de gran relevancia y necesidad, pues existía un desconocimiento de la situación real, lo cual dificultaba la implementación de medidas de cuidado, apoyo y atención adecuadas. Este estudio, por ende, ha contribuido al conocimiento teórico, práctico y metodológico de este complejo constructo educativo. El objetivo principal fue evaluar si se produjo algún cambio significativo en los niveles de salud mental positiva de los docentes de una institución educativa de nivel superior tanto al inicio como durante el desarrollo de la pandemia de covid-19. La pregunta de investigación formulada fue la siguiente: ¿existe algún cambio significativo en el nivel de salud mental positiva al inicio y a lo largo de la pandemia de covid-19 en los catedráticos de dicha organización? El enfoque ha sido cuantitativo, el alcance descriptivo e inferencial, para lo cual se aplicó la encuesta a 201 catedráticos seleccionados aleatoriamente. Los resultados sugieren que la capacitación a los docentes en el uso de las tecnologías de la información y comunicación, el apoyo psicológico y el esfuerzo para lograr los objetivos planteados favorecieron que el nivel de salud mental positiva en los catedráticos mencionados se mantuviera sin cambios significativos, es decir, los docentes presentaron frecuentemente un nivel de salud mental positiva al inicio y a lo largo del confinamiento; también se encontró que el 20 % de los catedráticos casi nunca presentaron autocontrol, autonomía y relaciones interpersonales.