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The RT-qPCR method is highly reliable for detecting SARS-CoV-2, but its cost hinders widespread use in large-scale screenings. This study aimed to assess and validate cost-effective alternative protocols for mass testing in low-morbidity, high-risk environments. 50 patient samples from the COVID in-patient care area and 50 samples from HGE personnel were analyzed using a pooling approach in varying prevalence settings. Individual RNA was pooled in groups of five, then tested for SARS-CoV-2 via RT-qPCR. This pooling strategy was employed for diagnosing SARS-CoV-2 in medical personnel, involving 885 HGE staff samples and 100 from HIES during the peak of the pandemic. Significant reductions in the number of RT-qPCR reactions were observed: a 77 % decrease in analysis cost for the 885 samples from HGE staff, and an 80 % reduction in reactions needed for the 100 samples from HIES staff. This study demonstrated the effectiveness and efficiency of analyzing pooled samples for widespread SARS-CoV-2 diagnosis in a population at low risk but with high exposure. This approach can be implemented in settings with high spatiotemporal density to mitigate hospital-based transmission risks.

This study analyzes the bioethical implications of using biotechnology for the conservation of agaves in the state of Hidalgo. Techniques such as in vitro cultivation, cryopreservation, and genetic improvement preserve the genetic diversity of these plants, which are essential for biodiversity and local cultural practices, particularly in the face of threats such as overexploitation and climate change. However, these technologies present ethical and bioethical challenges that require attention. An evaluation of the biotechnological impacts on genetic diversity and the sustainability of traditional practices for agave conservation in Hidalgo is presented, emphasizing ethical principles such as justice, non-maleficence, and respect for traditional knowledge. The results demonstrated that these technologies enable the propagation and conservation of key species, such as Agave salmiana and Agave mapisaga, while the bioethical challenges highlight the need to involve local communities in decision-making processes. It is concluded that biotechnology can complement in situ conservation while promoting social equity and cultural sustainability, positioning itself as a comprehensive tool for  protecting the biological and cultural heritage ofagaves.

Corynespora cassiicola causes losses in tomato production, agrochemicals are used to control it. Rhizobacteria, such as Bacillus spp. they represent an alternative to chemical products. The effect of Bacillus subtilis F8 and K47 against C. cassiicola was evaluated, mycelial and fungal growth was determined and the percentage of inhibition was calculated. Damage by the pathogen was evaluated in detached leaves inoculated with spores or cell-free filtrate. In B. subtilis, the presence of genes for surfactin biosynthesis, its emulsifying capacity and chitinolytic activity were determined. B. subtilis F8 and K47 reduced the mycelial growth of C. cassiicola 5.6 cm and 5.5 cm and the fungal growth by 79.4 % and 75.6 %, with an inhibition percentage of 69.1 % and 72.9 % respectively. On detached leaves, the application of spores or filtrates reduced disease symptoms by up to 63.8 %. Genes related to surfactin biosynthesis were detected in both strains, with an emulsifying capacity of 21.15 and 21.48 % and a chitinolytic activity of 0.165 μM mg-1 and 0.367 μM mg-1 respectively. B subtilis K47 and F8 present promising potential as an alternative in the control of C. cassiicola in tomato crops.

Fresh-cut mango is in high demand in developed countries; however, it deteriorates quickly and represents a suitable medium for microbial growth during storage. Chitosan coatings and other natural materials, such as essential oils, have been used to lessen these issues. The aim of this study was to evaluate the effect of chitosan (CH), mint essential oil (MEO) and their combination (CH+MEO) on the microbiological incidence, content of bioactive compounds, and antioxidant capacity of fresh-cut mango stored during 15 d at 5 °C. Microbiological analyses (mesophilics, psychrophilics, molds, and yeasts) were evaluated after 0, 7 and 15 d of storage. Physical (color and firmness) and chemical (total soluble solids, titratable acidity, ascorbic acid, phenols, β-carotene, and antioxidant capacity) analyses were performed every 3 d. The applied treatments successfully reduced microbial growth with the same intensity, furthermore, none of them caused significantly negative effects on color, firmness, total soluble solids, titratable acidity, and ascorbic acid. However, the highest total phenolics and β-carotene contents were obtained by CH+MEO, while fruit treated with CH and CH+MEO had the highest antioxidant capacity. The application of CH+MEO could be used to reduce its microbial load while increasing bioactive compounds and antioxidant capacity of fresh-cut mango.

 b-carotene is the most widely distributed carotenoid in foods and is characterized by its antioxidant and nutritional properties, so its consumption has health benefits. However, it is sensitive to factors such as the presence of oxygen, light and high temperatures. Therefore, the objective of the present study was to study the encapsulation process of b-carotene by freeze drying, using maltodextrin and mixtures with other encapsulating agents, evaluating the encapsulation efficiency, as well as the stability of the encapsulated b-carotene during storage at room temperature (30 °C) and refrigeration (8 °C), the antioxidant activity and bioaccessibility. The results showed that the mixtures of maltodextrin-gum Arabic and maltodextrin-soy protein presented higher encapsulation efficiency (50.40±3.96 y 49.18±5.18%) respectively. While the maltodextrin-soy milk mixture allowed the highest concentration of b-carotene to be maintained at the end of the study, as well as the one with the highest antioxidant activity (AA). Similarly, this mixture presented the highest bioaccessibility of b-carotene in the intestinal phase. Therefore, the use of different encapsulating agents for encapsulation by freeze drying could be used as a protective system and controlled release for sensitive fat-soluble compounds.

This work studied the removal capacity of a mixture of phenolic compounds (phenol, p-cresol, o-cresol) by denitrification; in addition, the effect of granular activated carbon (GAC) in the process carried out in UASB (up-flow anaerobic sludge blanket) reactors. The organic load was increased from 450 to 3250 mg C L-1d-1 by adjusting the HRT from 2 to 0.25 d in the reactor with GAC and the control reactor without GAC. The removal efficiencies of phenolic compounds increased as the organic load increased, obtaining values from 89.7 % to 95.5 % in the reactor without GAC and 95.8 % to 99.1 % in the reactor with GAC. The nitrate removal in the reactor with GAC reached 79.3 % to 98.0 % efficiencies, while the control obtained 64.8 % to 96.9 %. Finally, the maximum capacities of GAC were evaluated by adsorption isotherms, obtaining the following values (mg g-1): 164.6 for o-cresol, 134.5 for p-cresol, 110.7 for phenol, and 44.4 for nitrate. The results show the capacity of a denitrification process to remove a mixture of phenolic compounds. In addition, the reactor with GAC increased the removal efficiency of all compounds.

Abstract: Grasslands are considered one of the most threatened ecosystems in North America. One of the causes is the overgrazing, which reduces vegetation and causes erosion. Just a strategy to minimize it, could be the hydrological keyline design (HKD), which helps to conserve water, retains sediments, favors the growth of forage, and regenerates soil. The aim of the study was to evaluate the effect of HKD on the soil and vegetation of a rangeland ecosystem. Three treatments were established: 1). Control, 2). HKD and 3). HKD+Yeomans. The variables considered to measure the effect of the treatments were: humidity, compaction, erosion, vegetation cover and aerial phytomass production. The experiment was conducted under a completely randomized design. HKD treatments decreased erosion, the Control lost an average of 75 ton ha-1 more soil than HKD. While the plant coverage, in the HKD+Yeomans (42 %), followed by the HKD (34 %), surpassed the Control that presented only a 5 %. A similar result was observed with the pro-duction of phytomass, the HKD+Yeomans and HKD surpassed the Control, respectively, with 770 and 454 kg ha-1 (P = 0.099). HKD showed a positive effect on the soil and vegetation in the ecosystem.

 Turkey (Meleagris gallopavo) is the second largest contributor in poultry meat production after chickens. The study of microsatellite organization and distribution is of highly important in genomics and evolutionary students. The in silico mining for microsatellites leverages the power of computational biology to streamline and enhance the discovery of microsatellite markers, and reduce the cost of microsatellite detection. This study aimed at in silico mining microsatellite loci in the genome of domestic turkey. Reference sequences of the different chromosome obtained from NBCI and analyzed using Krait software.  Chromosome 4 had the highest number of perfect microsatellites, while chromosome 18 had the lowest. However, chromosome 27 had the highest relative abundance, followed by chromosome. Chromosome 18 again had the lowest relative abundance. For imperfect microsatellites, chromosome 4 had the most imperfect microsatellites and chromosome 18 had the least. A total of 121248 SSR primers were designed. These SSR loci and markers will be instrumental for linkage mapping and significantly improve research on turkey population genetics.

This study introduces evaporation deficit (DE) as a novel indicator to assess water balance and climate vulnerability in the state of Chiapas, Mexico. Analyzing data from 188 meteorological stations, we examined spatial and temporal variations in DE. Results indicate that DE is a robust tool for identifying regions and periods prone to drought or excessive moisture. A high spatial variability in DE distribution was observed, attributed to the complexity of hydrometeorological processes in the region. To estimate monthly DE from annual DE, the state was subdivided into three zones (A: R²=0.94, RMSE=0.216; B: R²=0.96, RMSE=0.065; C: R²=0.88, RMSE=0.415). This study demonstrates that DE is a valuable indicator for assessing water balance in Chiapas, providing insights with implications for water resources management and agriculture. However, the study acknowledges limitations related to data quality and spatial scale. Future investigations might explore the potential of DE as a tool for agricultural decision-making.