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This exploratory study investigated the relationships between time utilisation and the use of visual resources, supported by audiovisual records of the practices of pre-service chemistry teachers applying Teaching-Learning Sequences. The content analysis was based on analytical categories found in the scientific literature. The results showed a positive association between increased time spent using visualizations, diversification of pupils' actions, and the quality of the students' verbal interactions, through the predominance of conceptualisations in the submicro domain, with transitions between the macro and submicro domains. This study reinforces the importance of reflecting on the different ways of using visualizations in classroom time during chemistry teacher education, and the challenges of building and implementing chemistry teaching practices with scientific visualizations that are more integrated into the school curriculum.

Comprehensive curricula are described for middle and high school classrooms built around the synthesis of biodegradable calcium alginate capsules prepared from food-safe chemicals. Experiments and activities question whether calcium alginate capsules are a viable alternative to single-use water bottles and consider what characteristics are required to become commercially successful. Students prepare calcium alginate capsules using sodium alginate and calcium lactate and observe the physical properties of the fluid-filled pod. In the high school curriculum, capsules using alternative group 2 cation salts are made and compared qualitatively to the calcium alginate capsules. After exploring the capsules, students work collaboratively to design an inquiry experiment. The high school curriculum offers extensions such as analyzing a related literature article and creating professional research posters on their inquiry experiments. The middle school curriculum includes a scaffolded introduction on the topics of renewable vs nonrenewable resources and introduces simple polymer definitions and the concept of cross-linking through use of models. Both curricula align with Next Generation Science Standards (NGSS) around designing solutions to modern problems and carrying out investigations. Additionally, the experiment is ideal for safe, remote-learning instruction. Overarching connections between science and society are highlighted through the global plastics problem, and potential solutions are presented using the green chemistry principles of renewable feedstocks, design for degradation, and less hazardous chemical synthesis.

IntroductionSleep disorders are common in the general population, necessitating the search for new strategies to address this public health challenge. The study aims to describe the electrocorticographic and behavioral changes in sleep deprived Wistar rats exposed to varying doses of camphor, to assess its effects on sleep and its potential as a sleep-inducing drug.Materials and MethodsFor the electrocorticographic evaluation, seventy-two rats were randomly assigned to distinct groups: a control group, a sleep-deprived group, three sleep-deprived groups receiving 10, 20, and 30 mg/kg i.p. of camphor respectively, and three groups that received these doses without sleep deprivation. For the behavioral analysis, twenty-seven rats were divided into three groups, each receiving the same doses as the previous test.Results and DiscussionOur results showed that there was a decrease in the frequency of brain oscillatory patterns when camphor was administered at 10 mg/kg i.p. whereas there was a dose-dependent increase in the spectral power and distribution following the administration of 20 and 30 mg/kg i.p., with the emergence of Delta, Theta, Alpha, and Beta waves. As for the behavioral analysis, it was demonstrated that testicular relaxation, decreased motility, and light sleep induction also occurred in a dose-dependent manner. Thus, we conclude that camphor administration intensifies occipital electrocorticographic patterns in sleep-deprived rats, and its electrocorticographic and behavioral analysis could indicate a potential as a supporting agent in the insomnia treatment.

The design of emission abatement measures to effectively reduce high ground-level ozone (O3) concentrations in urban areas is very complex. In addition to the strongly non-linear chemistry of this secondary pollutant, precursors can be released by a variety of sources in different regions, and locally produced O3 is mixed with that transported from the regional or continental scales. All of these processes depend also on the specific meteorological conditions and topography of the study area. Consequently, high-resolution comprehensive modeling tools are needed to understand the drivers of photochemical pollution and to assess the potential of local strategies to reduce adverse impacts from high tropospheric O3 levels. In this study, we apply the Integrated Source Apportionment Method (ISAM) implemented in the Community Multiscale Air Quality (CMAQ v5.3.2) model to investigate the origin of summertime O3 in the Madrid region (Spain). Consistent with previous studies, our results confirm that O3 levels are dominated by non-local contributions, representing around 70 % of mean values across the region. Nonetheless, precursors emitted by local sources, mainly road traffic, play a more important role during O3 peaks, with contributions as high as 25 ppb. The potential impact of local measures is higher under unfavorable meteorological conditions associated with regional accumulation patterns. These findings suggest that this modeling system may be used in the future to simulate the potential outcomes of specific emission abatement measures to prevent high-O3 episodes in the Madrid metropolitan area.

Bigels (BGs) are innovative composite systems that integrate oleogel and hydrogel structures, and are gaining increasing attention for their unique textural and functional properties in food applications. This study evaluated the rheological and mechanical properties of egg white-based bigels incorporating candelilla wax (CW) as an oleogelator. The results indicate that different egg white protein (EWP) (5–10%) concentrations and hydrogel-to-oleogel ratios (20:80 to 80:20) significantly influenced the structural and functional properties of the bigels. Compression testing revealed no significant differences in strength across the tested range; however, higher EWP concentrations enhanced the stability of the BGs. Furthermore, increased candelilla wax oleogel (CWO) content (60%) markedly improved emulsion stability, resulting in superior strength, as confirmed by dynamic light scattering. Rheological studies demonstrated shear-thinning behavior, particularly at higher hydrogel content related to the oleogel (W/O), which exhibited the highest yield stress. Microstructural investigations confirmed the presence of a continuous oleogel phase within the bigels (W/O) and revealed the formation of a complex structure. These findings suggest that a reduced hydrogel-to-oleogel ratio can be utilized across various food systems, opening new possibilities for creating customized food structures with desirable textural and functional attributes.

DFT (Density Functional Theory) calculations were carried out to evaluate the chemical interaction of CO (carbon monoxide) and NO (nitrogen monoxide) molecules onto nanographenes (NGs) n = 1–6 units; thus, for this range adsorption process is exhibited, excepting for n = 5 desorption is favored. On the other hand, dioxide titanium clusters (TiO2) n = 1–4 were proposed to adsorb CO molecule, atop and parallel adsorption sites were considered to attach CO molecule onto these clusters and four possible isolated models (C1-C4) are generated and as result of this chemical interaction, physisorption was obtained. In order to improve the adsorption of CO molecule, (TiO2)n−CO clusters are deposited onto (NG)2 to play the role as substrate, namely coronene (C) and then a set of nanocomposites are generated to analyze changes on adsorption tendency, for the above systems just CO molecule is considered. Some chemical and structural transition are obtained for largest sizes as well as adsorption energy values are more favored for C−(TiO2)3−CO system due to the close proximity between titanium atom of C-(TiO2)3 clusters and this chemical specie. Therefore, there are substantial chemisorption values in this instance due to the active sites. The values of the electronic gap do not exhibit significant variations, among these nanocomposites, however, the HOMO isosurfaces are shown in distinct ways, and for n ≤ 2 systems examined in this paper, LUMO isosurfaces are displayed at the center of the cluster. In all systems analyzed, the electronic transference goes from chemical species toward atoms at the adsorption site. These results suggest that these C−(TiO2)n nanocomposites are ideal candidates to storing or sense different sort of gases; thereby, these findings can be employed to design a kind of gases storage device for environmentally friendly energy applications.

Heterogeneous photocatalysis is an advanced, efficient oxidation process that uses solar energy to be sustainable and low-cost compared to conventional wastewater treatments. This study synthesized BiOI/Fe3O4 using the solvothermal technique, evaluating stoichiometric ratios of Bi/Fe (2:1, 3:1, 5:1, and 7:1) under simulated solar irradiation to optimize the degradation of caffeic acid, a pollutant found in wastewater from the wine and pisco industry. The nanomaterial with a 5:1 ratio (BF-5) was the most effective, achieving a degradation of 77.2% in 180 min. Characterization by X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Brunauer–Emmett–Teller (BET), Barrett–Joyner–Halenda (BJH), Fourier Transform Infrared Spectroscopy (FTIR), Diffuse Reflectance Spectroscopy (DRS), and Vibrating Sample Magnetometry (VSM) showed that BF-5 has a porous three-dimensional structure with BiOI nanosheets coating the Fe3O4 surface, while retaining the pristine BiOI properties. The magnetite provided magnetic properties that facilitated the recovery of the photocatalyst, reaching 89.4% recovery. These findings highlight the potential of BF-5 as an efficient and recoverable photocatalyst for industrial applications. The technical, economic, and environmental feasibility were also evaluated at the technological readiness level (TRL) to project solar photocatalysis in real applications.

Tofu is obtained by heating soymilk, to which a coagulant, such as calcium sulfate or magnesium chloride, is added to make it curdle. This study aimed to parameterize the effects of the following three alternative organic coagulant types: apple, rice, and white vinegars, used in different proportions. Six treatments were established with three concentrations (1%, 3%, and 5%), evaluating the coagulation time and curd yield. The treatments with the lowest coagulation time were analyzed for texture by TPA, color through the CIEL*a*b scale, protein content, and moisture. The results showed that the rice vinegar + 3% white vinegar (T6C3) treatment showed the lowest coagulation time (0.78 min). The 5% apple vinegar (T1C5) treatment provided the highest curd yield, averaging 23.73%. This treatment’s protein and moisture contents were 3.93% protein and 69.73% moisture, confirming that better texture characteristics are recorded in tofu at lower pH values. The TPA results showed that using apple and rice vinegars as coagulants provided a challenging, less cohesive, more adhesive, and less elastic tofu. White vinegar provided a soft, more cohesive, less adhesive, and more elastic tofu. In the color analysis, it was observed that tofu coagulated with apple vinegar showed a tendency toward a yellow color, and tofu coagulated with rice and white vinegars showed a tendency toward a white color. These findings parameterize the effects of using each type of vinegar as a coagulant. These organic coagulants provide faster coagulation times and desirable texture characteristics, thus offering a practical alternative to traditional coagulants in tofu manufacturing.

Statistical education at university level faces significant challenges, particularly with the rapid advancements in technology and evolving teaching methods. Updating teaching methodologies for statistics in higher education is essential. Information technologies can greatly enhance the learning of statistical content, but many existing platforms are not well-suited for university contexts, either due to language barriers or how the content is presented (often confusing, with limited explanations or lacking context). It is crucial to have a student-centered platform that addresses these issues, ensuring an effective and efficient learning experience. This study introduces “EstApp”, an innovative mobile application prototype designed for teaching and learning descriptive statistics in university courses. The application was developed using the Design Thinking methodology, which emphasizes user experience and focuses on the needs of the end users. The design process involved stages of empathizing, defining, ideating, prototyping, and testing, culminating in validation through user tests with university students and professors. This study concludes that EstApp’s functionalities enhance understanding of (1) statistical models through interactive graphs and data visualizers; (2) probability concepts via a probability calculator; and (3) descriptive statistics through real-time data generation and visualizers.

In this study, a new and simple glassy carbon electrode modified with carbon nanohorns (SWCNH/GCE) was used for the determination of Cr(VI) in aqueous matrices via adsorptive cathodic stripping voltammetry (AdCSV). The modified electrode was characterized via field emission scanning electron microscopy and cyclic voltammetry, which revealed a homogeneous distribution of spherical agglomerates of SWCNH on the electrode surface. The modification increased the electrochemically active area from 0.10 cm2 ± 0.01 (GCE) to 0.16 cm2 ± 0.01 (SWCNH/GCE). The optimized analytical conditions were as follows: a supporting electrolyte (0.15 mol L−1 HCl), an accumulation potential of 0.8 V versus Ag/AgCl, and an accumulation time of 240 s. Validation of the analytical methodology was performed, obtaining a linear range between 20 and 100 µg L−1, a limit of detection of 3.5 µg L−1, and a limit of quantification of 11.6 µg L−1 with good accuracy and precision. The method was applied to the analysis of spiked tap water samples, and the results were compared using a flame atomic absorption spectrophotometer (FAAS) with no significant statistical differences.

Coffee is part of our daily lives since it is a drink with a symbolic value, both in our social relationships and as a stimulating drink. The main objective of this paper is to conduct a risk characterization of fluoride overexposure from the consumption of these beverages; for this purpose, in the present study, the fluoride concentration was determined in 80 samples of different brands of coffee commonly consumed in the Canary Islands, and the risk derived from their intake was then evaluated. Significant differences (p < 0.05) were found between the coffee brands soluble Nescafé Classic®, Saimaza®, Auchan®, Tirma® soft blend, and Hacendado® and the other analyzed brands. The brand that recorded the highest mean fluoride levels is “Hacendado descafeinado®” (0.308 mg/L). The problem with coffee is not the fluoride it contains but the fact that, according to the survey results, most coffee drinkers brew their coffee with tap water (over 51% of respondents use tap water). The results of the fluoride content in coffee prepared with tap water from the different areas of Tenerife in the Canary Islands (metropolitan, northern, and southern areas) have reported higher concentrations of fluoride: north (max. concentration found of 16.68 mg/L), south (max. concentration found of 8.47 mg/L) and metropolitan (max. concentration found of 4.73 mg/L). Coffee has not been identified as a risk of dietary overexposure to fluoride; however, the use of tap water for its brewing has been identified as a factor that considerably increases its concentration. Therefore, the use of bottled water is recommended, especially in regions such as the Canary Islands, which have high concentrations of fluoride in their water.

Solar radiation, specifically ultraviolet radiation (UVR), is one of the harmful external factors that affect the integrity of the skin upon sun overexposure. Its detrimental effects include skin aging (photoaging), pigmentation disorders, and skin cancer. Upon UVR exposure, a cascade of different cellular responses is initiated, giving rise to inflammatory processes, oxidative stress, protein misfolding, and DNA lesions, among other effects. Therefore, there is a growing need to explore and characterize new compounds for safeguarding the skin from solar radiation-induced damage. In this work, we analyze the antioxidant and anti-inflammatory capacities of the Mn (II) quinone complex (4QMn) in different cellular models and human skin explants. Importantly, our results suggest that 4QMn is able to ameliorate the oxidative damage produced by protein aggregation by reducing ROS levels, mitochondrial ROS (MitoROS), and DNA oxidative damage (8OH-dG) in a protein accumulation model. These findings suggest that the 4QMn compound could mitigate the deleterious effects of different sources of oxidative damage.

Nowadays, transportation fuels such as diesel or gasoline are standardly produced from crude oil refining. These petroleum-based products are gradually replaced by more environmentally friendly sources, such as Fischer–Tropsch diesel fractions and other biofuels. The present work reports the distillation of Fischer–Tropsch (FTS) waxes and its use for fuel production by (i) blending the FTS wax diesel fraction with fossil diesel (7:93; 15:85; 30:70; and 50:50 wt.%) and (ii) blending the FTS wax heavy fraction (360–700 °C) with vacuum gas oil (10–50 wt.%) followed by hydrocracking at industrial operating conditions (T = 420 °C, WHSV = 0.5–1.0 h−1, P = 10.0 MPa). The obtained products in both cases were analysed and compared with standard EN590 for petroleum-diesel fuels. Overall, our results point to the suitability of the distillation of FTS waxes for renewable fuel production, either by straight blending of the diesel petroleum-based products or co-hydrocracking of the heavy fraction with vacuum gas oil.

This paper presents an application for a molybdenum disulfide nanomaterial with multiwalled carbon nanotubes (MoS2@MWCNT/E) in a modified electrode substrate for the detection of uric acid (UA). The modified electrode generates a substantial three-fold increase in the anodic peak current for UA compared to the unmodified MWCNT electrode (MWCNT/E). The MoS2@MWCNT/E surface was characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) and electrochemical impedance spectroscopy (EIS). The achieved detection limit stood at 0.04 µmol/L, with a relative standard deviation (RSD) of 2.0% (n = 10). The method’s accuracy, assessed through relative error and percent recovery, was validated using a urine standard solution spiked with known quantities of UA.

This manuscript presents an examination of the impact of geometrical and physical parameters on highway design speeds, critical for traffic safety and efficiency. Originating from a classical dynamics discussion in an undergraduate automotive technology engineering class, an exploration of the consequences of different geometrophysical considerations on a vehicle’s dynamics over pavement surfaces is developed. Considering various analytical models, an assessment of their principles and the significance of geometric and physical concepts involved in the problem is made, such as plane of motion and trajectory curvature radius, on safe (non slippage) operational speeds. The subsequent comparative study shows that one of the most accepted models in highway design regulations in México, when used as reference, yields percentage error differences respect to others of 0≲%EMax≲5, as well as a consistent trend for relatively underestimating safe highway operational speeds. A discussion of the immediate implications of these findings, emphasizing the necessity of experimental studies to validate theoretical predictions, is presented. This work contributes to the field by providing a detailed comparison of analytical models under a general applied science perspective, suggesting modifications to current highway design practices in México based on geometrophysical insights. In summary, this work’s main aim is to shed light on the intricacies of determining safe design speeds from an applied sciences point of view, while also calling for a reevaluation of the existing guidelines to enhance highway design and safety.

Biochar (BC), which can be produced from several feedstocks, has been widely studied. However, the BC derived from highly pyrolytic shrubs, such as broom and gorse, has been less frequently used and only partially characterized. These wastes, when used for the preparation of biochar, can fix carbon and contribute to environmental conservation, helping to achieve sustainable development objectives. Eight biochars from broom and gorse were produced and fully analyzed, providing a more complete and novel description, with new insights for assessing their utilization. The aims of this study were to elucidate the effects of feedstock, pyrolysis temperature, and residence time on biochar properties and to assess the adequacy of these biochars as fuel. Elemental and proximate analyses and estimations of the lower and higher heating values were performed, and physical and chemical properties, as well as several other related energy indices, were determined. The experimental results showed that the temperature was a key factor in the properties of the biochars, while residence time was less important. The BCs obtained from the two feedstocks did not show important effects on the properties, which is consistent with the fact that they are woody legumes. These biochars had a high carbon content and were thermally stable. The BCs also had a high calorific value and suitable energetic properties. Additionally, their PAH contents were low, indicating that the use of these biochars would be safe. In conclusion, broom- and gorse-derived biochars can be considered as renewable fuels for green energy production.

High internal phase emulsion (HIPE) templating is a well-established method for the generation of polymeric materials with high porosity (>74%) and degree of interconnectivity. The porosity and pore size can be altered by adjusting parameters during emulsification, which affects the properties of the resulting porous structure. However, there remain challenges for the fabrication of polyHIPEs, including typically small pore sizes (∼20–50 μm) and the use of surfactants, which can limit their use in biological applications. Here, we present the use of gelatin, a natural polymer, during the formation of polyHIPE structures, through the use of two biodegradable polymers, polycaprolactone-methacrylate (PCL-M) and polyglycerol sebacate-methacrylate (PGS-M). When gelatin is used as the internal phase, it is capable of stabilising emulsions without the need for an additional surfactant. Furthermore, by changing the concentration of gelatin within the internal phase, the pore size of the resulting polyHIPE can be tuned. 5% gelatin solution resulted in the largest mean pore size, increasing from 53 μm to 80 μm and 28 μm to 94 µm for PCL-M and PGS-M respectively. In addition, the inclusion of gelatin further increased the mechanical properties of the polyHIPEs and increased the period an emulsion could be stored before polymerisation. Our results demonstrate the potential to use gelatin for the fabrication of surfactant-free polyHIPEs with macroporous structures, with potential applications in tissue engineering, environmental and agricultural industries.

Agavins are reserve carbohydrates found in agave plants; they present texture-modifying properties and prebiotic capacity by increasing the viability of the intestinal microbiota. Through its hydrolysis, agave syrup (AS) can be obtained and can be used as a sweetener in food matrices. The objective of this work was to evaluate the effect of the variation in the content of agavins and AS on the physical, structural, and viability properties of Saccharomyces boulardii encapsulates incorporated into gelatin gummies. An RSM was used to obtain an optimized formulation of gelatin gummies. The properties of the gel in the gummy were characterized by a texture profile analysis and Aw. The humidity and sugar content were determined. A sucrose gummy was used as a control for the variable ranges. Alginate microcapsules containing S. boulardii were added to the optimized gummy formulation to obtain a synbiotic gummy. The viability of S. boulardii and changes in the structure of the alginate gel of the microcapsules in the synbiotic gummy were evaluated for 24 days by image digital analysis (IDA). The agavins and agave syrup significantly affected the texture properties (0.85). The IDA showed a change in the gel network and an increase in viability by confocal microscopy from day 18. The number of pores in the gel increased, but their size decreased with an increase in the number of S. boulardii cells. Agavins and cells alter the structure of capsules in gummies without affecting their viability.

A Pickering double emulsion (DE) with an outer (O:W2) interface stabilized by cellulose nanocrystals (DE-CNC) was designed as a co-delivery systems for chlorogenic acid (CA) and curcumin, then compared with a control DE emulsion with an O:W2 interface stabilized with sodium caseinate (DE-NaCas). DE-CNC was more resistant to creaming during storage (6.79%, day 42) and showed higher encapsulation efficiency (EE) of CA (>90%). Conversely, both DEs exhibited similarly high EE for curcumin (>97%). The ζ-potential values were highly negative in both DEs, but tended to be lower in DE-CNC due to the highly negative charge of the CNCs. DE-CNC allowed for a steady release of CA during the oral, gastric, and intestinal phases of digestion, while a total release of CA was already observed in the gastric phase in case of DE-NaCas. The bioaccessibility of CA was similar in both DEs (~57–58%). Curcumin was mainly released in the intestinal phase with both DEs, reaching slightly lower bioaccessibility values with DE-CNC. The use of CNCs as a stabilizer for the outer interface of DEs is a promising strategy to increase the stability and EE of these systems, providing oral co-delivery vehicles capable of releasing significantly bioactive compounds during the intestinal phase of digestion.

The enzymatic extraction of proteins from fish biomasses is being widely investigated. However, little or almost no research has paid attention to the exploitation of unsorted fishery biomasses. This work is part of a larger study, Part I of which has already been published, and focuses on an extensive characterization of two collagenous samples, namely gelatin (G) and hydrolyzed gelatin peptides (HGPs), extracted from a dehydrated fish biomass coming from unsorted canned yellowfin tuna side streams. The results indicate crude protein fractions of 90–93%, pH values between 3 and 5, white–yellow colors, collagen-like FTIR spectra, and 17% in terms of total amino acid content. Viscosity and the study of dynamic viscous–elastic behavior were analyzed. Thermo-gravimetric analysis was performed to assess the residual ashes. Both samples were investigated to determine their molecular weight distribution via size-exclusion chromatography, with a higher total average molecular weight for G compared to HGPs, with values of 17,265.5 Da and 2637.5 Da, respectively. G demonstrated technological properties similar to analogous marine gelatins. HGPs demonstrated antioxidant activity as per FRAP assay. All the results open up new perspectives for the potential use of these substances in biodegradable packaging, dietary supplements, and skin care cosmetics.

Fish is a food that is widely produced, marketed, and consumed around the world. It is a basic component of human nutrition due to its chemical and nutritional composition, but at the same time is highly perishable and susceptible to contamination throughout the food chain, compromising its quality and safety. Fishing and aquaculture products, being perishable, require adequate processing and preservation to maintain their quality and safety as much as possible until their acquisition and final consumption. Different preservation methods have been developed and used to extend the shelf life of fish products with minimal impact on their nutritional and organoleptic properties. Therefore, the objective of this document is to provide, through the search, analysis, and selection of information from various databases such as Scopus, Scielo, Web of Science, and Google Scholar, among others, a general and basic informative description of fish, aimed at academics, producers, industrialists, and the general public that allows them to identify the basic points in the processing and preservation of the quality and safety of fish. Aspects related to production; the nutritional qualities of fish; the various physical, chemical, and biological contaminating hazards of fish; the control and prevention of contaminants and diseases for consumers; and food legislation for products are included, as well as the main traditional and modern methods applied in the preservation of fishery and aquaculture products to maintain their nutritional value, quality, and safety that allow for the availability of food and the protection of public health.

The electric vehicle deployment, due to the plans defined according to the energy transition objectives, produces new challenges for the electrical system. These challenges are associated with the charging infrastructure of these vehicles since they require a high current during specific periods, which can increase losses in the network, overload the lines, or cause voltage drops that affect the system’s stability. To solve these challenges, one of the possible solutions is the investment in new network infrastructure to face the increase in demand, such as the construction of new transformation centers or new medium and low-voltage lines. However, in the case of rural networks with a small number of users, these investments may not be viable. This article analyzes the possible impacts of connecting electric vehicles in a rural low-voltage network located in a Spanish municipality, as well as possible implementable solutions that do not require investment in new infrastructure. The number of connected vehicles has been calculated based on the national plan for 2030, and the network model used is based on actual data provided by the distribution company that operates in the area.

The mango fruit is of great economic value worldwide and of great nutritional importance. Its functional effects are due to numerous important nutrients and bioactive compounds. In this review, the benefits of mango fruit (pulp, peel, and seed) for human nutrition and health are detailed. The first part of the review presents the nutrient and phytochemical content of the mango fruit, and the second part addresses its health effects. The very diverse phytochemical components in mango fruit can be classified into several groups including macronutrients such as carbohydrates (sugars, pectin, and cellulose), proteins, lipids (Ω-3 and Ω-6 fatty acids); micronutrients such as vitamins A and C, minerals, pigments (chlorophylls, carotenoids, and anthocyanins, depending on the cultivar), phenolic compounds (phenolic acids and flavonoids), and volatile compounds. The beneficial effects of mango fruit and its components have been studied on different non-communicable diseases such as obesity, type 2 diabetes mellitus, hypertension, and cancer. A great diversity of research approaches have been used to study mango fruit health benefits, and those can be grouped into three main categories: a) those that present the associations or direct effects of the edible portion of the fruit on health through observational epidemiological studies and clinical trials; b) in vivo and in vitro experimental approaches that address either the physiological effects or mechanisms of several kinds of extracts or purified components of mango fruit (pulp, peel and seed), and c) preclinical and clinical studies that explore the possible pharmacological uses of mango fruit. Current scientific understanding of mango health benefits suggest that consumption of mango fruit and its byproducts containing bioactive components can be useful as part of a healthy diet in order to reduce the incidence of health problems.

Abstract Purpose The Pharmacy Service of the Infanta Leonor University Hospital acquires, compounds, distributes and dispenses more than 3000 L of methadone oral solution to Drug Addiction Patients Centers per year. Our purpose is to develop and validate an improved high performance liquid chromatography (HPLC) method to quantify methadone hydrochloride in a new oral solution with methylhydroxybenzoate (methylparaben) and propylhydroxybenzoate (propylparaben) to be implemented in physicochemical stability studies that allow to provide more information and even to increase the beyond-use date. Methods A HPLC-Agilent® 1100 equipment, comprising a quaternary pump and an ultraviolet diode-array-detector (DAD) was used. An analytical method development and validation was completed. The curve was constructed from methadone working concentrations of 75–125% (7.5, 9.0, 10.0, 11.0 and 12.5 mg/mL) to assess the linear relationship between the concentration of the analyte and the obtained areas. Precision and accuracy were calculated. Detection and quantification limit (LD, LQ) were estimated using the EURACHEM method. Forced-degradation studies were also performed. Results Chromatographic conditions were: flow rate 1.6 mL/min; mobile phase 55% acetonitrile and 45% sodium phosphate 25 mM (pH = 10); injection volume was 5 µL. The column was a Waters-XTerra™ RP18, maintained at 40 °C. DAD was λ = 254 nm. Retention times for methadone, methylparaben and propylparaben were 4.34, 0.70 and 0.88 min respectively. The method was linear (y = 284.3x − 97.8, r = 0.996). Instrumental precision was 0.33% for standards (n = 10); intra-assay precision 0.53% (n = 6) and inter-assay precision 1.95% (n = 12). The relative standard deviation percentage for accuracy was 1.28%. The recovery percentage was 101.5 ± 1.5%. LQ and LD were 2.18 µg/mL and 2.0 µg/mL respectively. The most destabilizing conditions were oxidizing and alkaline. The chromatograms confirmed no interference with the methadone signal. Conclusions The HPLC method has proved to be valid and reproducible for methadone quantification in a new oral solution with methylparaben and propylparaben. This assay is a rapid, simple and reliable technique that can be used in daily analysis and physicochemical stability studies.

The mulching of agricultural soils has been identified as a viable solution to sequester carbon into the soil, increase soil health, and fight desertification. This is why it is a promising solution for carbon farming in Mediterranean areas. Models are used to project the effects of agricultural practices on soil organic carbon in the future for various soil and climatic conditions, and to help policy makers and farmers assess the best way to implement carbon farming strategies. Here, we modified the widely used RothC model to include mulching practices and their direct and indirect effects on soil organic matter input, soil temperature changes, and soil hydraulic balance. We then calibrated and tested our modified RothC (RothC_MM) using the dataset collected in two field mulching experiments, and we used the tested RothC_MM to estimate the expected soil carbon sequestration due to mulching by the year 2050 for the Valencian Community (Spain). Our results show that RothC_MM improved the fit with the experimental data with respect to basic RothC; RothC_MM was able to model the effects of mulch on soil temperature and soil water content and to predict soil organic carbon (SOC) and CO2 observations taken in the field.

Red wine contains polyphenols which are extracted during the winemaking process. However, winemaking is not an extraction; therefore, the resulting byproducts still have a substantial polyphenol content. The aim of this study was to compare two methods for the extraction of phenolic compounds: maceration and matrix solid-phase dispersion (MSPD). Grape pomace (Vitis vinifera var. Cabernet Sauvignon) from a winery in Querétaro, Mexico was used. The optimal conditions for both methods were identified. Phenolic compounds and antioxidant activity were the response variables. A central composite design was used (Minitab 17) for the extraction by maceration. The maceration time (1, 4, 12, 20, and 24 h) and the ratio of ethanol (50 to 80%) acidified with 1% HCl were the two factors studied. For the MSPD extraction, sea sand was used as a dispersant, and a 22 factorial design was employed for the evaluation, with the elution volume and the ratio of sample/dispersant being the two factors analyzed. The optimal extraction method was MSPD with 96 mL (acidified ethanol) as the elution volume and a 1:2 ratio of sample/dispersant. Using these conditions, 14.01 ± 0.19 mMol TEAC/100 g db (Trolox equivalent of antioxidant capacity) of grape pomace was obtained, whereas the total phenolic content was 2836.73 ± 41.90 mg GAE/100 g db. These values are greater than those obtained by maceration. These conditions are close to those predicted by the model (analysis of variance (ANOVA) with a level of significance of 5% (p < 0.05) and a Tukey comparison test for determining significant differences in the comparison of results).

When classifiers face imbalanced class distributions, they often misclassify minority class samples, consequently diminishing the predictive performance of machine learning models. Existing oversampling techniques predominantly rely on the selection of neighboring data via interpolation, with less emphasis on uncovering the intrinsic patterns and relationships within the data. In this research, we present the usefulness of an algorithm named RuLer to deal with the problem of classification with imbalanced data. RuLer is a learning algorithm initially designed to recognize new sound patterns within the context of the performative artistic practice known as live coding. This paper demonstrates that this algorithm, once adapted (Ad-RuLer), has great potential to address the problem of oversampling imbalanced data. An extensive comparison with other mainstream oversampling algorithms (SMOTE, ADASYN, Tomek-links, Borderline-SMOTE, and KmeansSMOTE), using different classifiers (logistic regression, random forest, and XGBoost) is performed on several real-world datasets with different degrees of data imbalance. The experiment results indicate that Ad-RuLer serves as an effective oversampling technique with extensive applicability.

In the last few years, there has been increasing interest in the use of block-based programming languages as well as in the ethical aspects of Artificial Intelligence (AI) in primary school education. In this article, we present our research on the automatic identification of the need for assistance among primary school children performing Scratch exercises. For data collection, user experiences have been designed to take into account ethical aspects, including gender bias. Finally, a first-in-class distance calculation method for block-based programming languages has been used in a Long Short-Term Memory (LSTM) model, with the aim of identifying when a primary school student needs help while he/she carries out Scratch exercises. This model has been trained twice: the first time taking into account the gender of the students, and the second time excluding it. The accuracy of the model that includes gender is 99.2%, while that of the model that excludes gender is 91.1%. We conclude that taking into account gender in training this model can lead to overfitting, due to the under-representation of girls among the students participating in the experiences, making the model less able to identify when a student needs help. We also conclude that avoiding gender bias is a major challenge in research on educational systems for learning computational thinking skills, and that it necessarily involves effective and motivating gender-sensitive instructional design.

With the ultimate goal of developing models that involve the use of environmental variables, a GIS-based application is being developed that is circumscribed to the region of Galicia (Spain). Ten-minute data of six meteorological variables were collected from 150 stations of the MeteoGalicia network over a period of 18 years, but the time series data are not complete. In order to estimate missing rainfall data, four imputation methods were evaluated in this study: missForest, MICE, Amelia II, and inverse distance weighting (IDW). Crossvalidation results show that the precipitation is out of phase in the different stations due to their geographical locations, and the imputation can be improved with a displacement of the time series; on the other hand, the missForest method provided better results in the imputation of this meteorological variable than the MICE, Amelia, or IDW.

Eugenol is a natural compound with well-known repellent activity. However, its pharmaceutical and cosmetic applications are limited, since this compound is highly volatile and thermolabile. Nanoencapsulation provides protection, stability, conservation, and controlled release for several compounds. Here, eugenol was included in β-cyclodextrin, and the complex was characterized through X-ray diffraction analysis (XRD) and Fourier-transform infrared spectroscopy (FTIR). Additionally, we used molecular dynamics simulations to explore the eugenol–β-cyclodextrin complex stability with temperature increases. Our computational result demonstrates details of the molecular interactions and conformational changes of the eugenol–β-cyclodextrin complex and explains its stability between temperatures 27°C and 48°C, allowing its use in formulations that are subjected to varied temperatures.

Leishmaniasis is considered one of the most untreated tropical diseases in the world. In this study, we investigated the in vitro leishmanicidal activity and cytotoxicity of various isolated lichen substances, including atranorin (1), usnic acid (2), gyrophoric acid (3), salazinic acid (4), galbinic acid (5), and parietin (6), and some semi-synthetic imine derivatives of usnic acid (7, 8, 9) and atranorin (10, 11, 12, 13). Imine condensation reactions with hydrazine and several amines were assisted by microwave heating, an efficient and eco-friendly energy source. The most interesting result was obtained for compound 2, which has high leishmanicidal activity but also high cytotoxicity. This cytotoxicity was mitigated in its derivative, 9, with better selectivity and high antileishmanic activity. This result may indicate that the usnic acid derivative (9) obtained using condensation with two cyclohexylamine groups is a promising lead compound for the discovery of new semisynthetic antiparasitic drugs.

This study presents for the first time a scalable process for the extraction of valuable proteins starting from samples of unsorted mixed tuna scraps which were previously dehydrated by an industrial patented process. The aims of this work were both to avoid the onerous sorting step of tuna leftovers, which generally consists of isolating skin and bones for collagen/gelatin extraction, and to improve the logistic of managing highly perishable biomass thanks to the reduction in its volume and to its microbiological stabilization. In view of a zero-waste economy, all the protein fractions (namely, non-collagenous proteins NCs and ALKs, gelatin, and hydrolyzed gelatin peptides, HGPs) isolated in the proposed single cascade flowchart were stabilized and preliminarily characterized. The extraction flowchart proposed allows one to obtain the following most promising compounds: 1.7 g of gelatin, 3.2 g of HGPs, and 14.6 g of NCs per 100 g of dehydrated starting material. A focus on oven-dried gelatin was reported in terms of proximate analysis, amino acid composition, color parameters, FT-IR spectrum, pH, and viscoelastic properties (5 mPa·s of viscosity and 14.3 °C of gelling temperature). All the obtained extracts are intended to be exploited in food supplements, feed, fertilizers/plant bio-stimulants, packaging, and the cosmetic industry.

MOLECULAR SYMMETRY AND DESYMMETRIZATION REACTIONS IN ORGANIC SYNTHESIS. Molecular Symmetry has found several applications in Organic Chemistry. The aim of this article is to showcase its relevance as a tool for synthetic planning. Natural Products and synthetic compounds with pharmaceutical applications were selected to highlight desymmetrization reactions that make use of organocatalysis, biocatalysis or by transition metals. The recognition of structural patterns in retrosynthetic analysis is discussed for compounds that exhibit explicit or hidden symmetry. Limitations of the aforementioned strategies are also described, as well as the untapped potential, challenges and frontiers yet to be explored regarding these concepts.

Abstract: Exploratory quantum materials discovery remains crucial to progress in material science. Due to the grand challenges that we are facing in predicting these materials and their properties from scratch, chemical design principles remain a key ingredient for the discovery of new materials. Chemical heuristics, structure, bonding, as well as global and local symmetries are at the very foundation of materials properties. In this regard, in this research, we aim to identify functional materials by composition-structure-property understanding. Materials discovery consists of a subset of methods and design principles that go hand in hand until a desired material or property is realized. However, materials synthesis is still far from a rational design approach. Rather, materials, and especially metastable materials, have to be accessed and synthesized in an exploratory, laboratory-intensive fashion. At the same time, quantum materials discovery is a vibrant highly active field of research that has seen various leaps of progress in recent years, and that holds the promise for many more in the coming years. Here, we lay out how we are discovering new materials and new materials physics in our and other chemical physics, or physical chemistry research groups, and how chemistry and chemical synthesis play a crucial role in this process.

Se investigó el mecanismo y la cinética de la pirolisis en fase gaseosa del 4-cloro-1-butanol a nivel DFT. La reacción da como productos tetrahidrofurano, formaldehido, propeno y cloruro de hidrogeno. El mecanismo de eliminación molecular sugiere dos vías de reacción. La primera vía se produce a través de un estado de transición cíclico de cuatro miembros, donde el nivel de teoría WB97XD/6-31G++(d,p) mostró resultados cercanos con los parámetros cinéticos experimentales. La segunda vía ocurre en dos etapas, la primera se da mediante un estado de transición cíclico de cuatro miembros y la segunda con estado de transición cíclico de seis miembros, los niveles de teoría que dieron resultados más cercanos a los experimentales fueron B3LYP/6-31G(d,p) y WB97XD/6-31G++(d,p), para primera y segunda etapa respectivamente. La ruptura del enlace C-Cl, debido a su polarización en el enlace , es el paso determinante de la velocidad en ambas vías de reacción. El análisis topológico NCI se usó para determinar las interacciones no covalentes es todas las estructuras. La variación de la fuerza de los enlaces involucrados en las transiciones se midió mediante el índice IBSI, lo que permitió verificar el mecanismo propuesto

Nejayote and pericarp derived from nixtamalization are an environmental problem. Therefore, there is research interest in using these residues as new compostable and environmentally friendly materials. This work aimed to create, characterize (color, thickness, water solubility, water adsorption capacity, microstructure, and degradability), and apply biodegradable films using residues of nejayote and pericarp of nixtamalized popcorn. Three types of films were compared, pericarp (P), nejayote–pericarp (NP), and nejayote (N), and were applied to avocado stored at room temperature. Results showed that the P film was the best because it was significantly (p < 0.05) more transparent (L = 94.75 ± 2.21) and thicker (0.27 ± 0.02 mm). It had higher water adsorption capacity (162.60 ± 14.05%) and higher elastic modulus and toughness (0.004 ± 0.001 MPa, 2.25 ± 0.25 J/m3) values than the N and NP films; in addition, its microstructure showed a roughness value (Ra) of 6.59 ± 0.57 nm that was intermediate compared to other films. Moreover, the P coating slowed down the maturing process of avocado and showed a visual effect against fungal infection. All films were generally soft and had a degradation time between 11 and 12 days. The novelty of this study is to provide the alternative of using nejayote and pericarp in a film that is compostable and maintains the lifespan of avocados.