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Methane degradation in biotrickling filters: Recyclable materials as a support medium
Full text linkBiofiltration is an alternative method for reducing methane, a greenhouse gas with public health risks and climate impacts. However, its feasibility is often limited by the high costs of organic beds and inadequate surface area. This study evaluated the removal efficiency and specific methane removal capacity of biotrickling filters (BTFs). In the air quality laboratory of the Universidad de Nariño, methane was diluted to a concentration of 4% in two BTFs with recycled material (polyethylene terephthalate - BTF1 and expanded polystyrene - BTF2) and inoculated with a methanotrophic microbial consortium. The reactors were operated in parallel for 24 hours per day with countercurrent flow under controlled conditions (25°C, 10 psi, neutral pH), TRLV of 31 min, and a flow rate of 6 L h-1 with a concentration of ~2000 ppmv. BTF1 achieved a maximum removal efficiency (RE) of 75%, higher than BTF2’s 60%, likely due to the greater external specific area of PET. BTF1 and BTF2 showed a positive influence of temperature and humidity on RE, while pH had an opposite effect. However, BTF2 exhibited a higher specific removal capacity (SRC) due to its superior surface properties, though its performance was limited by filter bed compactation. In conclusion, BTFs using these two materials as support media demonstrate biological efficiency in methane removal, highlighting their potential for treating methane emissions from the anaerobic decomposition of organic matter in agricultural activities
Development and validation of a liquid chromatographic method to analyze cannabinoids in plants and oils
Full text linkThe therapeutic properties of Cannabis sativa have been widely investigated and have become a subject of great importance for the treatment of diseases such as epilepsy, as well as pain management in patients with cancer, arthritis, and Parkinson's disease, among others. The commercialization of Cannabis products has flourished due to these properties, highlighting the need to develop analytical methods for quality control of products marketed for medicinal purposes, as well as for Cannabis research. The objective of this work was to develop an HPLC-DAD-based analytical method for Cannabidiol (CBD), Cannabinol (CBN), and Tetrahydrocannabinol, (∆9-THC) cannabinoids tests in commercial Cannabis oils and plant material samples. Regarding the suitability of the system, the developed analytical method exhibited symmetrical peaks, with good resolution and symmetry. The system’s precision was adequate, with relative standard deviation (%RSD) values of less than 5%, and accuracy in terms of recovery greater than 90% for the extractions. Analysis of commercial samples revealed high ∆9-THC content (2.6-42.55 mg/mL) and low CBD content (0-4.3 mg/mL). The plant material sample analyzed correspond to a non-psychoactive chemotype (∆9-THC ≤ 1%) with a higher CBD content (8.0 mg/g). Considering the above, the developed method is suitable for the analysis of plant material and cannabis oils
Plantain socio-productive system (Musa AAB): An initiative to revalue agriculture in western Antioquia
Full text linkScattered across all departments, plantain has long been a traditional crop within the Colombian peasant economy, making it fundamental to food security. The western region of the department of Antioquia has excellent production potential, given its optimal agroecological conditions and comparative advantages for production and marketing. However, emerging organizational processes, the loss of agricultural tradition, a lack of agro-industry, and inadequate soil and water management have hindered agricultural development. Mining extraction activities and agricultural production coexist in the region, leading competition for productive resources. De facto value chains provide an analytical and operational framework for identifying stakeholders, prioritizing technological limitations, and coordinating territorial and institutional stakeholders. Therefore, this research aimed to characterize plantain socio-productive units and value chains in the municipalities of Cañasgordas, Giraldo, Buriticá, and Santa Fe de Antioquia. The study was conducted in 2022 and 2023, following a qualitative descriptive method under multivariate analysis, social network analysis, and elements of the governance analytical framework. The production method is a low-tech system with a high potential for satisfying local and regional markets. Despite projects promoting plantain plantations, fundamental technological problems persist that must be addressed by building cross-cutting and specific capacities for co-validating technologies focused on generating quality plant material and managing pests and diseases
Así Habló Zaratustra, Friedrich Nietzsche (1883)
Full text linkAsí habló Zaratustra narra las enseñanzas de Zaratustra, un sabio que desciende de su retiro en las montañas para compartir su visión del mundo. A través de discursos poéticos y simbólicos, la obra reflexiona sobre la superación del ser humano, la creación de nuevos valores y la crítica a la moral tradicional. Nietzsche propone la figura del superhombre, la afirmación de la vida y la voluntad de poder, invitando al lector a cuestionar sus creencias y a forjar su propio sentido de la existencia
Return to Work, Family Functionality, and Social Support in Women Who Experienced Pregnancy After Age 35 in Antioquia, Colombia
Full text linkIntroduction: Pregnancy after the age of 35 is an increasingly common trend in the contemporary world; however, aspects such as returning to work and its relationship with family functionality and social support remain underexplored. Objective: To assess work reentry, family functionality, and social support in women who experienced pregnancy after the age of 35 in Medellín and the metropolitan area of Antioquia, Colombia. Materials and Methods: A descriptive study measuring sociodemographic characteristics, social support, family functionality, and satisfaction with work reentry following pregnancy in 106 women from the department of Antioquia, Colombia. Results: Of the participants, 82.1% had an education level higher than secondary school, and over half belonged to the upper-middle class. No participant with normal family functionality reported unsatisfactory work reentry, and approximately 80% of these women were still employed. 75% of the participants reported not experiencing postpartum depression; however, only 43.8% self-reported normal family functionality. Conclusion: For a pregnant woman over 35 years of age, a functional family and a positive perception of social support play a beneficial role in work reentry
