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En el departamento de Petén, en Guatemala, se ubican empresas agroexportadoras de papaya (Carica papaya L.) con requerimientos hídricos para su producción. Sin embargo, su extracción puede ocasionar a mediano plazo el agotamiento de los mantos subterráneos y superficiales. Por ello, el objetivo de la presente investigación fue evaluar la sostenibilidad de los sistemas de riego en seis empresas agroexportadoras de papaya (Carica papaya L.) del departamento de Petén, Guatemala. Para el análisis de la sostenibilidad en las empresas objeto de estudio se utilizó estadística descriptiva e inferencial, aplicando medidas de dispersión, variabilidad, asimetría y pruebas de normalidad de datos. Con esta información fue posible la propuesta de un modelo para evaluar la gestión sostenible del recurso hídrico. Como instrumento de recolección de datos se utilizó la observación, un cuestionario estructurado y otro no estructurado, además de una cédula de registro conformada por indicadores a nivel experimental que permitieron proponer el modelo con un índice para evaluar la sostenibilidad. A partir de la aplicación del modelo se obtuvo el Índice de Impacto Sostenible del Riego con una valoración de 0.64, lo cual localiza a los sistemas de riego de las empresas bajo estudio en la categoría poco sostenible. Por esto, se recomienda implementar sistemas de gestión basados en planes de restauración vegetal en zonas de recarga hídrica, estudios de calidad de aguas superficiales y subterráneas, así como de impacto ambiental, y generar una cultura de educación sostenible y de uso eficiente del agua para riego.

Cucumber is a vegetable crop of economic importance in Mexico. In 2023, fresh or frozen cucumber and pickle international sales reached USD 783M, placing Mexico in second rank among countries with the highest currency inflow in the world. This crop is mostly grown under protected environments with new production technologies, including rootstocks that are tolerant to biotic and abiotic factors that limit the yield and quality of the harvest. Therefore, the goal of this work was to assess three cucurbits as rootstocks (Cucurbita maxima, Cucurbita moschata and Citrullus lanatus), as well as studying the response of cucumber crop to the tested rootstocks. The following treatments were assessed: T1:PSP = cucumber Cv. Paraizo F1 without rootstock; T2:P/MA = cucumber grafted over Cucurbita maxima; T3:P/MO = cucumber grafted over Cucurbita moschata; T4:P/CL = cucumber grafted over Citrullus lanatus Citroides Var. The assessed variables included the number of fruits per plant (NFPP), fruit weight per plant (PFPP), average fruit weight (PPF), plant dry weight (PSP), xylem vessel area (AVX), number of xylem vessels (NVX), vascular bundle area (AHV) and number of vascular bundles (NHV) in roots (R), basal stalk (TB) and apical stalk (AT). Significant differences among treatments were found in the results for variables: NFPP, highlighting that T2:P/MA was superior by 46.15% versus T1:PSP and by 67.69% versus T3:P/MO. Regarding PFPP, T2:P/MA achieved the highest weight (5445 g), as it proved superior by 99.45% than the cucumber without rootstock (T1:PSP). Regarding PSP, T2:P/MA achieved the highest weight (196.65 g), significantly exceeding T1 by 137.5%. Regarding AVXR, T4:P/CL had the highest value (30,063 µm2). Regarding NHVR, watermelon had (T4:P/CL) 39.33% more vascular bundles than the root system of cucumber (T1:PSP). Treatments T2:P/MA and T4:P/CL had the highest values at AVXTB, while for variable NVXTB, treatments T3:P/MO and T2:P/MA were almost equal, surpassing non-grafted cucumber by 175.47%. However, T2:P/MA showed the greatest AHVTB, and T1:PSP was significantly superior to T3:P/MO, by 34.93%, for NHVTB. Furthermore, positive and significant correlations were found among PFPP, AHVR, and AVXTB, as well as among PSP, AVXTB, and AHVTB. Therefore, we may say that having a larger area of vascular vessels in the roots and a larger area of xylem vessels in the basal stalk leads to higher fruit yields per plant. In the same vein, the use of rootstocks is a sustainable alternative to increase fruit yield.

This study explores an eco-friendly method for recovering platinum group metals from a synthetic automotive three-way catalyst (TWC). Bioleaching of palladium (Pd) using the thiosulfate-copper-ammonia leaching processes, with biogenic thiosulfate sourced from a bioreactor used for biogas biodesulfurization, is proposed as a sustainable alternative to conventional methods. Biogenic thiosulfate production was optimized in a gas-lift bioreactor by studying the pH (8–10) and operation modes (batch and continuous) under anoxic and microaerobic conditions for 35 d. The maximum concentration of 4.9 g S2O32− L−1 of biogenic thiosulfate was reached under optimal conditions (batch mode, pH = 10, and airflow rate 0.033 vvm). To optimize Pd bioleaching from a ground TWC, screening through a Plackett–Burman design determined that oxygen and temperature significantly affected the leaching yield negatively and positively, respectively. Based on these results, an optimization through an experimental design was performed, indicating the optimal conditions to be Na2S2O3 1.2 M, CuSO4 0.03 M, (NH4)2SO4 1.5 M, Na2SO3 0.2 M, pH 8, and 60 °C. A remarkable 96.2 and 93.2% of the total Pd was successfully extracted from the solid at 5% pulp density using both commercially available and biogenic thiosulfate, highlighting the method’s versatility for Pd bioleaching from both thiosulfate sources.

Abstract To analyze the effectiveness of dexamethasone in preventing upper airway obstruction (UAO) symptoms after extubation and the need of reintubation in critically ill children. Multicenter, prospective, double-blind, randomized, phase IV clinical trial involving five pediatric intensive care units. Children between 1 month and 16 years-of-age intubated for more than 48 h were included. Patients were randomized to receive placebo or dexamethasone 0.25 mg/kg every 6 h, 6-to-12 h prior to extubation (four doses). 48 h follow-up was carried out after extubation. Severity of UAO symptoms (Taussig score, stridor) and reintubation requirement were compared. 147 patients were randomized (10 were excluded), 70 patients received dexamethasone and 67 placebo. No global differences were found in the presence of stridor or moderate-to-severe UAO symptoms (Taussig ≥ 5), but Taussig ≥ 5 was less frequent in patients less than 2 years-of-age treated with steroids (p = 0.014). Median Taussig score was lower in the dexamethasone group 1 h after extubation, p 5 days, reintubation due to UAO was higher in the placebo group (2.4% vs. 14.3, p = 0.052). Nebulized epinephrine and budesonide were required more frequently in the placebo group in the first 2 h (p = 0.041) and 1 h (p = 0.02) after extubation, respectively. No relevant side effects were observed. Dexamethasone prior to extubation did not significantly reduce moderate-severe UAO symptoms, except for patients under 2-years of age. Dexamethasone could decrease Taussig score and the need of rescue therapies, as well as reintubation rates in those intubated for more than 5 days.

Aim. To evaluate retinal vascular perfusion and density by optical coherence tomography angiography (OCTA) before, during, and after hypoglycemia in individuals with diabetes mellitus with or without diabetic retinopathy (DR). Methods. A focused clinical history was performed, followed by an ophthalmological examination to document retinopathy status. OCTA was performed at baseline, at hypoglycemia, and at glucose normalization. Eye tracking and eye alignment devices on the platform were used to obtain a macular thickness cube (512 × 128) and vascular perfusion and density protocols of 3 × 3 mm. Retinal vascular reactivity was analyzed with superficial plexus vascular perfusion and density protocols on OCTA. Results. Fifty-two participants encompassing 97 eyes fulfilled the eligibility criteria. Their mean age was 42.9 ± 15.1 years (range, 22 to 65), and 20 (38.2%) were men. We found a statistically significant difference in vascular perfusion and density when comparing all groups at baseline. The controls had higher vascular perfusion and density values than the cases. Vascular perfusion and density were significantly reduced in all groups during the hypoglycemia episode, except for vascular density in DR cases. Conclusion. Acute hypoglycemia significantly alters the retinal vascularity in DM patients with and without DR, suggesting that repeated episodes of acute hypoglycemia could exacerbate retinopathy in the long term.

Multiple paternity is common to all sea turtle species, but its causes and consequences are hard to ascertain and the behaviors and success of males difficult to observe. This study aims to describe patterns of multiple paternity for olive ridley turtles Lepidochelys olivacea at Playa de Escobilla, an ‘arribada’ (mass-nesting) site on the Mexican Pacific coast with over a million clutches laid each reproductive season. A total of 15 females and their hatchlings were sampled during 3 arribada events which occurred over the 2016-2017 nesting season. Females and hatchlings (N = 329) were genotyped at 5 microsatellite loci, from which we inferred the alleles of 46 contributing males. Multiple paternity was detected in 60% of the analyzed clutches, which were sired by a range of 2 to 7 males. Multiple paternity rates differed significantly across arribada events, suggesting more males achieved fertilizations earlier in the breeding season. Paternal contribution in 6 of the clutches with multiple paternity was skewed towards a single male; the remaining clutches had a homogeneous male contribution. However, our results are based on relatively small within-arribada sample sizes. The frequency of multiple paternity among turtle clutches laid on this arribada beach could be related to the density of breeding individuals in the reproductive patch off Playa de Escobilla, rather than to the nesting population size or female size.

Introducción: El nivel de riesgo de consumo se establece a partir de la exposición que tiene una persona a ciertos factores de riesgo o características individuales, familiares o sociales, que posibilitan o aumentan el consumo de sustancias psicoactivas (SPA). Objetivo: Este estudio tuvo como propósito relacionar el nivel de riesgo de consumo de SPA con el uso problemático de videojuegos y redes sociales, a fin de establecer su posible papel como factores de riesgo de tipo social. Método: Se realizó un estudio de tipo cuantitativo con un diseño no experimental transversal de alcance descriptivo correlacional con la participación de 736 estudiantes. Se emplearon como instrumentos de recolección de datos el cuestionario sociodemográfico, prueba de tamizaje ASSIST 3,1, cuestionario de adicción a redes sociales – ARS y el cuestionario de Experiencias Relacionadas con los Videojuegos – CERV. Resultados: Algunos resultados sugieren mayor exposición al consumo de sustancias alcohólicas, derivados del tabaco, del cannabis y mayores niveles en el uso problemático de redes sociales y videojuegos. Conclusiones: A partir de lo hallado, las evidencias apuntan a que el aumento de riesgo no depende de la tipología familiar, al contrario de lo que pasa con el sexo, a su vez el consumo de tabaco, alcohol, cocaína, inhalantes, sedantes y opiáceos dependen de variaciones.

Habanero chili pepper has great economic importance in Mexico, but its production is limited due to different factors that affect quality. Given the high demand and prices of the fruit, the production of this crop is spreading to other regions in search of new production systems. The aim of this research work was to assess the yield and antioxidant components of the fruit by supplementing potassium from organic sources. The “Campeche”, “Palenque”, and “Jaguar” varieties were studied in five NPK treatments; replacing the % of potassium with humus and compost: (T1) 240-200-120+50% of K from liquid earthworm humus; (T2) 240-200-180+25% of K from liquid earthworm humus; (T3) 240-200-120+50% of K from vermicompost; (T4) 240-200-180+25% of K from vermicompost; and (T5) 240-200-240 (control, 100% chemical nutrition). For yield components, there were significant differences, highlighting the importance of the nutrition source for the yield and weight of fruits per plant. The control (T5) presented a value of 39 t·ha−1 and was similar to treatments T2 and T3 with a supplement of 25 and 50% organic K. For the polar and equatorial diameter of fruit, as well as for plant height and leaf area, treatments supplemented with 50% organic K (T1 and T3) were more effective. For the varieties evaluated, no differences in yield and fruit weight were found; however, Campeche produced more fruits per plant with a greater equatorial diameter, while Palenque obtained fruits with a greater polar diameter and taller plants. The results of antioxidant compounds show that organic K supplementation improves the quality of total carotenoids, β-carotenes, and xanthophylls compared to 100% chemical fertilization, since total carotenoid content is improved by 54.2%, β-carotenes by 46.4%, and xanthophylls by 37.8%, respectively. The Campeche variety was the one that presented the best fruits with the highest antioxidant quality. These results indicate a positive effect of the combined application of chemical fertilizer with worm humus on yield and its components in pepper and other crops and show an economic, ecological, and sustainable alternative to the production of habanero chili pepper.

The circular economy is based on using waste generated from any process to obtain products with zero residues’ criteria. This research was focused on pepper waste from the polyphenolic extraction method. Pepper waste was evaluated in batch and semi-continuous regime anaerobic digestion, adding, as catalysts, absorbent nanoparticles and/or using pretreatment strategies. The best methane yields were obtained from SB1 (assay without pretreatment in pepper waste): 464 ± 25 NL kg VS−1 for batch assays; and from period II (1.47 g VS L−1 d−1) of S2 (assay of pig manure and pepper waste with thermal pretreatment): 160 NL/kg VS−1 for semi-continuous experiments. However, a kinetic study showed a methane production rate higher for SB2 (assay with nanoparticles as catalyst) than SB1 in batch assays.