The acetalization or transacetalization reactions produce acetals or ketals used in cosmetics, food, pharmaceuticals, and fuel additives. Besides synthesizing several products, the acetalization or transacetalization reactions can protect carbonyl groups, 1,2 and 1,3-diols in multi-step synthesis. This work studies the transacetalization of glycerol with 2,2-dimethoxypropane (2,2-DMP) to yield 2,2-dimethyl-4-hydroxymethyl-1,3-dioxolane (solketal) by catalyzing with USY, HBeta, and HZSM-5 zeolites under cleaner and mild reaction conditions (reaction temperature: 25 °C; 2,2-DMP/glycerol molar ratio: 1; reaction time: 1 h; and catalyst concentration: 0.05-5 wt.%). For catalyst concentration equal to or greater than 2,5 wt.%, glycerol conversion stabilized near 96-97% for the three zeolites tested. The product selectivities also assume a constant value, close to 97% for solketal. For the lowest concentration of catalyst, the influence of the zeolite properties on the glycerol conversion, such as acidity and the strong/weak acid site ratio, was observed. Concerning the selectivity of the products, the results suggested that it can be based on zeolite topology, active sites at the particle surface, and the relative amount of micro and mesoporous HBeta, the most selective catalyst for acetals production, was reused at least once without loss of activity and selectivity. cosmetics food pharmaceuticals additives products groups 12 2 1, 1,3diols 13diols diols 1,3 3 multistep multi step synthesis 2,2dimethoxypropane 22dimethoxypropane dimethoxypropane 2,2 2,2DMP 22DMP DMP (2,2-DMP 2,2dimethyl4hydroxymethyl1,3dioxolane 22dimethyl4hydroxymethyl13dioxolane dimethylhydroxymethyldioxolane dimethyl 4 hydroxymethyl dioxolane solketal (solketal USY HBeta HZSM5 HZSM 5 HZSM- temperature °C C 2,2DMP/glycerol 22DMPglycerol DMPglycerol DMP/glycerol ratio time h 0.055 0055 0.05 0 05 0.05- wt.%. wt wt.% . wt.%) 2, 9697% 9697 96 97 96-97 tested value strongweak strong weak observed topology surface production 3diols 13 2dimethoxypropane 22 2DMP 2dimethyl4hydroxymethyl1 3dioxolane 055 005 0.0 wt. 969 9 96-9 dimethylhydroxymethyl 2dimethyl4hydroxymethyl 00 0. 96-

The increase in the average temperature of the Earth due to excess CO2 and other greenhouse gases has caused glaciers to melt and sea levels to rise. The burning of fossil fuels is one of the main causes of this problem, so the use of biofuels is important for mitigating this environmental impact. In Brazil, biodiesel is mixed with mineral; however, irregularities have been detected, reducing the expected positive effects. Therefore, this study proposes the use of multivariate curve resolution with alternating least squares (MCR ALS) to quantify the content of methyl palm oil biodiesel in diesel blends and determine the concentration of the adulterant automotive lubricating oil in the blend. The model for quantifying biodiesel in diesel obtained R2 = 0.9997, root mean square error of calibration (RMSEC) = 0.56% (v v-1) and prediction (RMSEP) = 0.65% (v v-1), while the determination of adulteration in the biodiesel-diesel blend showed RMSEC = 0.67% (v v-1), RMSEP = 0.81% (v v-1) and R2 = 0.9992. These results demonstrate the ability of the models developed to predict both the content and quantity of possible adulterants in blends of palm oil biodiesel and mineral diesel, contributing to the quality control of this fuel. CO rise problem impact Brazil however detected effects Therefore MCR ALS R 09997 0 9997 0.9997 (RMSEC 056 56 0.56 v v1 1 v-1 (RMSEP 065 65 0.65 v1, , biodieseldiesel 067 67 0.67 081 81 0.81 09992 9992 0.9992 fuel 0999 999 0.999 05 5 0.5 v- 06 6 0.6 08 8 0.8 099 99 0.99 0. 09 9 0.9

ABSTRACT The correct use of tyres on agricultural tractors, in respect of the terrain and the type and internal pressure of the tyre, are factors that influence the performance of the tractor. The aim of the present study was to evaluate the operating performance of an agricultural tractor fitted with two types of traction device (radial and diagonal tyres) at different pressures, and operating on soil with two levels of moisture. The experiment was conducted on a dystrophic Red Yellow Argisol, with tests to evaluate the performance of the tyres under specific working conditions. Tractive power and tractive force, wheel slip and fuel consumption were evaluated. For each of the conditions under evaluation, the radial configuration showed better performance than the diagonal configuration, the effect being more significant at the lower pressure and under low soil moisture. The use of radial tyres led to an increase in traction capacity and drawbar power, with a reduction in fuel consumption, especially at higher slip rates. tractors tyre pressures moisture Argisol force evaluated evaluation rates

Seeking a viable alternative to fossil fuels as the primary energy source, bioethanol has emerged as a promising second-generation fuel derived from lignocellulosic biomass. With Brazil ranking pineapple as the third most produced fruit in temporary crops, this study aims to assess the impact of chemical pretreatment techniques, specifically organosolv and diluted acid, on the residual biomass of Pérola pineapple peel to enhance bioethanol production. Employing an experimental design that incorporates temperature, reaction time, and varying concentrations of organic solvent, the study examines their effects on the susceptibility of the substrate to saccharification for future bioethanol generation. Factors such as alphacellulose, hemicellulose, and lignin were evaluated in triplicate and subjected to statistical analysis using the Tukey test with a confidence level of 95%. Upon application of the pretreatment methods, it was observed that the organosolv solvent approach (utilizing water and ethanol) with sulfuric acid exhibited superior sugar conversion, yielding the highest concentration of xylose at 9.13 g L-1. Additionally, the pretreated biomass contained 1.38 g L 1 of cellobiose, 3.11 g L-1 of arabinose, and 3.76 g L-1 of glucose. This technique demonstrates promising potential for obtaining fermentable sugars crucial for bioethanol production. source secondgeneration second generation crops techniques production temperature time alphacellulose hemicellulose 95 95% methods utilizing ethanol conversion 913 9 13 9.1 L1. L1 1. Additionally 138 38 1.3 cellobiose 311 3 11 3.1 L- arabinose 376 76 3.7 glucose 91 9. 31 3. 37 7

ABSTRACT The mechanized cutting of sugarcane requires improvements, as cutting tools can affect the longevity of sugarcane fields and increase production costs. Furthermore, these tools can increase the energy demand of machines in the field. This study evaluated the sugarcane harvester performance equipped with different basal cutting devices: impact cutting (blades) and continuous cutting (saws) in three commercial sugarcane production areas. The experimental design was completely randomized in a 3 × 2 factorial scheme with six repetitions. Effective fuel consumption and harvesting capacity were evaluated. The saws increased fuel consumption per area by 3.9 and 8.9% per Mg harvested. The crop’s yield characteristics determine harvesting systems’ energy demand. For yields above 90 Mg ha-1, energy demand has stabilized up to 120 Mg ha-1. The fuel demand for harvesting ranged between 1.0 and 1.2 L Mg-1 of harvested material. Regardless of the cutting system, each Mg requires 37.3 kJ of energy to be removed from the field. improvements costs Furthermore field devices blades (blades (saws areas repetitions 39 9 3. 89 8 8.9 crops crop s systems ha1, ha1 ha 1, 1 ha-1 12 ha1. 1. 10 0 Mg1 Mg- material system 373 37 37. 8. ha-

RESUMO O corte mecanizado da cana-de-açúcar necessita de aprimoramentos, visto que as ferramentas de corte podem afetar a longevidade dos canaviais e aumentar os custos de produção. Além disso, essas ferramentas podem aumentar a demanda energética das máquinas no campo. Este estudo avaliou o desempenho de colhedoras de cana-de-açúcar equipadas com distintos mecanismos de corte basal: corte por impacto (lâminas) e corte contínuo (serras) em três áreas comerciais de produção de cana-de-açúcar. O consumo efetivo de combustível e a capacidade efetiva de colheita das máquinas foram avaliados em cada tratamento. O delineamento experimental adotado foi inteiramente casualizado em esquema fatorial 3 × 2 com seis repetições. As serras aumentaram o consumo de combustível por área em 3,9 e 8,9% por Mg colhido. As características produtivas da cultura determinam a demanda energética dos sistemas de colheita. Para produtividades acima de 90 Mg ha-1, a demanda energética estabilizou-se até 120 Mg ha-1. A demanda de combustível para a colheita variou entre 1,0 e 1,2 L Mg-1 de material colhido. Os resultados mostram que independente do sistema de corte, cada Mg de cana colhida necessita em média de 37,3 kJ de energia para ser retirado do campo. canadeaçúcar açúcar aprimoramentos disso campo basal lâminas (lâminas (serras canadeaçúcar. açúcar. tratamento repetições 39 9 3, 89 8 8,9 colhido ha1, ha1 ha 1, 1 ha-1 estabilizouse estabilizou se 12 ha1. 1. 10 0 Mg1 Mg- 373 37 37, 8, ha-

Abstract Introduction: Spills of flammable liquids can lead to serious accidents, mainly in industrial plants and on roads. To prevent the spread of spills, various forms of collection are used, such as absorption with porous solids. Agroindustrial waste can be used as sorbent materials for flammable liquids. Objective: To determine the sorption capacity of the residual empty-fruit bunch of oil-palm (Elaeis guineensis) and the macaw palm (Acrocomia sp.) nutshell for four organic flammable liquids. Methods: The residual biomasses of E. guineensis and Acrocomia sp. were assessed as sorbents for spilled fuels (diesel, jet fuel, commercial kerosene, and gasoline). Volumetric measurement of liquid-fuel absorption at 24 ºC was taken during a week. Desorption was measured at 50 ºC as the drying kinetics, by using moisture scales. Results: The sorption capacity of the Acrocomia sp. material was not satisfactory, compared to the E. guineensis residual material, due to differences in the residual architecture of the organic material. This last can absorb 2.4 ± 0.2 cm3 g-1 at 24 ºC, during a one-week period. Diatomite absorbs greater quantities of the organic liquids but, the fluids diffusion at 50 ºC is 0.26 ± 0.09 times more slowly in the mineral matrix, because of the greater pore tortuosity in this mineral matrix. Conclusions: The oil-palm empty fruit bunch of E. guineensis, showed lesser but adequate performance than the sorbing behavior for fire hazard mitigation of diatomite. The nutshell of macaw palm (Acrocomia sp.) did not prove to be useful for this recovery operation.

Resumen Introducción: Los vertidos de líquidos inflamables pueden producir accidentes graves, principalmente en plantas industriales y en carretera. Para prevenir la dispersión de derrames, se utilizan diversas formas de recolecta, como la absorción con sólidos porosos. Residuos agroindustriales pueden ser aprovechados como materiales sorbentes de líquidos inflamables. Objetivo: Determinar la capacidad de absorción de las biomasas residuales del pedúnculo de la palma aceitera (Elaeis guineensis) y del endocarpio del fruto de coyol (Acrocomia sp.) para cuatro líquidos orgánicos inflamables. Métodos: Las biomasas residuales de E. guineensis y de Acrocomia sp. se evaluaron como sorbentes para combustibles derramados (diésel, queroseno de aviación, queroseno comercial y gasolina). Se midió la cantidad de líquido absorbida por las biomasas a 24 ºC durante una semana, y su cinética de desorción a 50 ºC, usando balanzas de secado. Resultados: La propiedad sorbente del material de Acrocomia sp. no fue satisfactoria, comparada con el pedúnculo de E. guineensis, debido a diferencias en arquitectura residual del material orgánico. Esta última biomasa muestra una capacidad de absorción para los combustibles de 2.4 ± 0.2 cm3 g-1 a 24 ºC. La diatomita absorbe mayor cantidad de los combustibles estudiados, pero la difusión de estos fluidos a 50 ºC por la matriz mineral es solo 0.26 ± 0.09 veces lo observado para el material de E. guineensis, como resultado del mayor grado de tortuosidad de los poros de la diatomita. Conclusiones: El pedúnculo de palma aceitera (E. guineensis) mostró un adecuado potencial desempeño para la aplicación pasiva en la mitigación de los riesgos de incendio, con respecto a la diatomita. El endocarpio del fruto de Acrocomia sp. no resultó útil para esta operación de recuperación.

Abstract Introduction: Gorse (Ulex europaeus, family Fabaceae) is an evergreen shrub native to Europe and invasive in the Andean high-mountain tropical paramos. Objective: To quantify the extent of a biological invasion within a paramo near Los Nevados National Natural Park in Tolima, Colombia, and evaluate bioeconomic solutions to encourage shrub eradication while promoting the local economy and industry. Methods: An object-based supervised classification approach was conducted using UAS (Uncrewed Aircraft Systems)-based RGB imagery and a Planet-derived NDVI (Normalized Difference Vegetation Index) layer, both from 2022, to quantify the area invaded. This value, the height obtained from a UAS-derived nDSM (Normalized Digital Surface Model), and a pair of allometric equations found in the literature were employed to estimate the gorse aboveground biomass (AGB) and aboveground available fuel, also known as fuel load. Then, documented bioethanol production estimations were applied to calculate its potential extraction based on the AGB values. Results: The invaded area was quantified to be 66 465 m2, with an overall accuracy rate of 85.3 %. Furthermore, the fuel load was found to be approximately half of the AGB, which poses a high risk of fire in the ecosystem. The findings also suggest that up to USD 88 933.7 could be generated if all gorse in the study area is exploited to produce bioethanol. Conclusions: This study underscores the urgency of managing the biological invasion of gorse in the Andean paramo and suggests the potential for bioeconomic solutions to mitigate the impact of these invasions.

Resumen Introducción: El retamo espinoso (Ulex europaeus, familia Fabaceae) es un arbusto perenne originario de Europa e invasor en los páramos andino-tropicales de alta montaña. Objetivo: Cuantificar la extensión de una invasión biológica dentro de un páramo cerca del Parque Nacional Natural Los Nevados en Tolima, Colombia, y evaluar soluciones bioeconómicas para fomentar la erradicación del arbusto y, al mismo tiempo, promover la economía e industria locales. Métodos: Se llevó a cabo una clasificación supervisada basada en objetos utilizando imágenes RGB tomadas con UAS (sistemas de aeronaves no tripulados) y una capa NDVI (índice de vegetación de diferencia normalizada) derivada de Planet, ambas de 2022, para cuantificar el área invadida. Este valor, así como la altura obtenida a partir de un nDSM (modelo digital de superficie normalizado) derivado de las imágenes UAS y un par de ecuaciones alométricas halladas en la literatura, se emplearon para estimar la biomasa aérea (AGB) y el combustible disponible superficial, también conocido como carga de combustible. Luego, se utilizaron estimaciones documentadas de producción de bioetanol para calcular su potencial extracción con base en los valores de AGB. Resultados: El área invadida se cuantificó en 66 465 m2, con una exactitud global del 85.3 %. Además, se encontró que la carga de combustible era aproximadamente la mitad del AGB, lo que representa un alto riesgo de incendio en el ecosistema. Los resultados también sugieren que se podrían generar hasta 88 933.7 dólares estadounidenses, si se explotara todo el retamo espinoso de la zona de estudio para producir bioetanol. Conclusiones: Este estudio resalta la urgencia de gestionar la invasión biológica del retamo espinoso en el páramo andino y sugiere potenciales soluciones bioeconómicas para mitigar el impacto de estas invasiones.

ABSTRACT The production process of non-centrifuged cane sugar (NCS) involves a significant release of steam and heat due to the evaporation of cane juices in saucepans over a solid fuel oven. This results in a warm and moisture-saturated environment, which can be suffocating for workers. This study aimed to evaluate the bioclimatic behavior of an NCS processing facility, based on the wet bulb globe temperature (WBGT) index. In addition, solutions are suggested to mitigate possible adverse effects of heat stress. This evaluation utilized computational simulations to determine the thermal comfort perceived by the workers. The accuracy of simulations was verified against temperature and relative air humidity data collected from the facility. Bioclimatic simulations encompassed twelve treatments, involving modifications to the enclosure on the walls and lantern window, incorporating three types of roof material. The WBGT index was determined by considering the effects of the radiant heat generated by the oven and the natural ventilation area on the facility’s temperature and relative air humidity. This helps to assess the comfort experienced by the workers. The thermal zone of the oven presented heat stress conditions; therefore, rest periods and mechanical ventilation were suggested when dissipating heat and steam through natural ventilation is not possible. For workers exposed to high temperatures and thermal radiation, the use of an aluminized apron and infrared goggles for eye protection was recommended. noncentrifuged non centrifuged (NCS moisturesaturated moisture saturated environment facility (WBGT addition treatments window material facilitys s conditions therefore radiation recommended

RESUMO O processo de produção de rapadura gera alta concentração de vapor e calor devido à evaporação do caldo da cana em panelas sobre forno a combustível sólido. Isso gera um ambiente quente e saturado de umidade que pode ser sufocante para os trabalhadores. Este estudo teve como objetivo avaliar as condições ambientais de uma instalação de processamento de rapadura, com base no Índice de Bulbo Úmido e Temperatura de Globo (IBUTG) e sugerir soluções para mitigar possíveis efeitos adversos do estresse térmico. Esta avaliação utilizou simulação computacional para determinar o conforto térmico dos trabalhadores. A simulação foi validada com dados de temperatura e umidade relativa do ar da instalação. As simulações bioclimáticas foram realizadas em doze tratamentos, modificando o fechamento nas paredes e lanternim, com três tipos de materiais de cobertura. Foi determinado o Índice IBUTG, considerando os efeitos do calor radiante gerado pelo forno, e pela área de ventilação natural sobre a temperatura e umidade relativa do ar no interior da instalação, e seu efeito no conforto dos trabalhadores. A zona térmica do forno apresentou condições de estresse térmico, portanto, foram sugeridos períodos de descanso e ventilação mecânica quando não for possível a evacuação do calor e vapor através da ventilação natural. O uso de avental aluminizado e óculos infravermelhos para proteção ocular foi recomendado para os trabalhadores expostos a altas temperaturas e radiação térmica. sólido IBUTG (IBUTG tratamentos lanternim cobertura portanto

Abstract: Environmental pollution from transportation has been a fundamental challenge for humanity throughout history, with conventional fuels contributing significantly to environmental degradation. This project seeks to suppress pollution and reduce noise generated by motorcycle taxis, whether for personal and/or private use. The main objective of the research work was to implement an electrolyzer in the combustion system of a motorcycle taxi to suppress environmental pollution and reduce noise. Methods included vehicle preparation, electrolyzer installation, battery adjustment, hydrogen generation, emissions measurement, safety, and data collection. As a result, the electrolyzer was implemented in the single-cylinder motorcycle taxi; The noise limit allowed at work in Peru is 85 dB, which is equivalent to 100 % noise at most; When using gasoline, a value of 76.4 dB was obtained, equivalent to 89.88 % noise, and when using hydrogen, a value of 71.7 dB was obtained, equivalent to 84.35 % noise, therefore, the total noise reduction was 4.70 dB (5.53 %) than established. The discussion highlighted that hydrogen is a clean fuel, with zero emissions and only emitting water vapor instead of polluting gases (5). The conclusion highlights the critical importance of the research, supported by the total reduction of 5.53 % of noise with this new technology and in turn external sources support that using hydrogen produced a smoother and quieter combustion; Regarding the useful life of the engine, due to the cleaner and more efficient combustion, the accumulation of waste was reduced, which benefits reducing the wear of internal components and the need for costly maintenance.

Resumen: La contaminación ambiental derivada del transporte ha sido un desafío fundamental para la humanidad a lo largo de la historia, con los combustibles convencionales contribuyendo significativamente a la degradación ambiental. Este proyecto busca suprimir la contaminación y reducir el ruido generada por mototaxis, ya sean de uso personal y/o privado. El trabajo de investigación tuvo como objetivo principal implementar un electrolizador en el sistema de combustión de un mototaxi para suprimir la contaminación ambiental y reducir el ruido. Los métodos incluyeron la preparación del vehículo, instalación del electrolizador, ajuste de la batería, generación de hidrógeno, medición de emisiones, seguridad y recolección de datos. Como resultado, se logró implementar el electrolizador en el mototaxi monocilíndrico; el límite de ruido permitido en el trabajo en el Perú es de 85 dB, que equivalen el 100 % de ruido como máximo; al utilizar gasolina se obtuvo un valor de 76.4 dB equivalentes a 89.88 % de ruido y al usar hidrógeno se obtuvo un valor de 71.7 dB siendo el 84.35 % de ruido, por lo tanto, la reducción total de ruido fue de 4.70 dB (5.53%) de lo establecido. La discusión destacó que el hidrógeno es un combustible limpio, con nulas emisiones y solo emitiendo vapor de agua en vez de gases contaminantes (5). La conclusión subraya la importancia crítica de la investigación, respaldada por la reducción total del 5.53 % de ruido con esta nueva tecnología y a su vez fuentes externas apoyan, que el utilizar hidrógeno produjo una combustión más suave y silenciosa. En cuanto a la vida útil del motor, la combustión más limpia y eficiente reduce la acumulación de residuos, lo que disminuye el desgaste de los componentes internos y la necesidad de mantenimientos costosos.

Abstract Taxonomic identification provides relevant and unique data for the management of woody resources. However, taxonomic analysis cannot provide information on other equally important aspects that allow us to understand the management of this resource. The characterization of the state of wood used as fuel will allow activities related to of firewood supply to be evaluated. The objective of this work is to understand the modalities of woody fuel acquisition among hunter-gatherer groups. For this purpose, the alterations present in carbonized wood remains from six archaeological sites in Argentine Patagonia were identified and characterized. The results obtained allowed the use of healthy, altered or green wood as fuel to be identified in each case. Moreover, the results enabled the management of wood fuel by societies characterized by high residential mobility to be discussed from a different perspective.

Resumen La determinación taxonómica proporciona datos relevantes y únicos sobre la gestión de los recursos leñosos. No obstante, el análisis taxonómico no puede dar información sobre otros aspectos igualmente importantes que permiten comprender la gestión de este recurso. La caracterización del estado de la madera utilizada como combustible permitirá evaluar las actividades de aprovisionamiento de la leña. El objetivo de este trabajo es comprender las modalidades de adquisición del combustible leñoso, entre grupos cazadores-recolectores. Con este objetivo se identificaron y caracterizaron las alteraciones presentes en restos de madera carbonizada, procedentes de seis sitios arqueológicos de la Patagonia argentina. Los resultados alcanzados permitieron identificar en cada caso, el uso de madera sana, alterada, verde, como combustible. Por otro lado, permitieron discutir desde una perspectiva diferente la gestión del combustible leñoso llevada a cabo por sociedades caracterizadas por una alta movilidad residencial.

Abstract Fires affect more natural surfaces than any other disturbance factor on the planet. They result from the interaction of fuel, dry environmental conditions, and an ignition source. In the state of Michoacán conditions are conducive for the annual occurrence of numerous fires. Remote sensing offers global, consistent and objective information on fires, with the generation of series of burned areas, such as the 500m MCD64A1 generated from MODIS data. The objective of this work was to analyze this series to know the fires that occurred in the entity between 2015 and 2022, considering vegetation covers affected (INEGI Series VII) precipitation and temperature. An average of 3 340.87 pixels with fires were recorded annually; 2021, during confinement due to the Covid-19 pandemic, was the year with the most fires (5 269 pixels) and 2022 with the fewest (2 398). The fires are concentrated in the driest and hottest months, mainly May (1551.00 pixels on average) and April (958.38 pixels); the highest number was recorded in April 2021 (2 347 pixels), and the second month with the most detections was May 2020 (2 094 pixels). Most events are associated with agricultural burning (48.41%), mainly in irrigated land, in spring and winter. Forest fires significantly affect temperate forests and associated secondary vegetation (32.85%); in tropical deciduous forest areas (17.14%), fires occur mostly in secondary vegetation. In years with an early onset of rains (2015 and 2018), fewer fires accumulated.

Resumen Los incendios afectan a más superficies naturales que cualquier otro factor de disturbio en el Planeta. Resultan de la coincidencia de combustible, condiciones ambientales secas y una fuente de ignición. En el estado de Michoacán existen las condiciones propicias para la ocurrencia anual de numerosas conflagraciones. La teledetección ofrece información global, consistente y objetiva sobre los incendios, con la generación de series de áreas quemadas, como MCD64A1 de 500m, generada con datos MODIS. El objetivo de este trabajo fue analizar esta serie para conocer los incendios ocurridos en la entidad entre 2015 y 2022, considerando las coberturas afectadas (Serie VII de INEGI), la precipitación y la temperatura. Se contabilizaron al año, en promedio 3 340.87 pixeles con incendios; 2021, durante la pandemia de Covid-19, fue el año con el mayor número de registros (5 269 pixeles) y 2022 con menos (2 398). Los incendios se concentraron en mayo (1551.00 pixeles en promedio) y abril (958.38 pixeles); el máximo número de incendios se detectó en abril de 2021 (2 347 pixeles), seguido de mayo de 2020 (2 094 pixeles). La mayoría de los eventos se asocian a quemas agrícolas (48.41%) en terrenos de riego, en primavera e invierno; los incendios forestales afectan sobre todo a bosques templados y a la vegetación secundaria asociada (32.85%); en zonas de bosque tropical caducifolio (17.14%), los incendios ocurren, en su mayoría, en vegetación secundaria. En los años con un inicio temprano de la temporada de lluvias (2015 y 2018) se acumularon menos incendios.

Abstract Climate change and the lack of fuel management in oak forests promote favorable conditions for the occurrence of forest fires. The objective of the present research was to know the relationship of dasometric variables, terrain slope (Pe), depth of leaf litter (Ph) and depth of mulch (Pm) on the fuel load in oak forests in the Mountain region of Guerrero. The dasometric variables mean diameter (Dm), mean height (Am), number of trees ha-1 (Na) and basal área ha-1 (Ab) were evaluated according to the sampling design of the 2015 National Forest and Soil Inventory; At each sampling site, three planar intersection lines were established for sampling woody material (Ml), leaf litter (Ho) and mulch (Ma) were collected in 0.09 m2. The total fuel load ranged from 23.2 to 46.5 t ha-1 (p < 0.05), the Ma presented the highest load with 43%, followed by woody material (Ml) and leaf litter (Ho) with 31 and 26%. The total charge (Ct) showed a relationship with Ma, Ho and Ml (r = 0.81 to 0.41), Ho with Ph and Pe (r = 0.71 and -0.72). The c1h showed a relationship with Na, Ma, Pe and Dm (r = 0.72 to -0.41), the c10h showed a correlation with Ab, Pe and Na (r = 0.51 to 0.42). The dasometric variables only explain the fuel load with a diameter less than or equal to 2.5 cm.

Resumen El cambio climático y la falta de manejo a los combustibles en los bosques de encino propicia condiciones favorables para la ocurrencia de incendios forestales. El objetivo de la presente investigación fue conocer la relación de variables dasométricas, pendiente del terreno (Pe), profundidad de la hojarasca (Ph) y profundidad del mantillo (Pm) sobre la carga de combustible en bosques de encino en la región Montaña de Guerrero. Las variables dasométricas diámetro medio (Dm), altura media (Am), número de árboles ha-1 (Na) y Área basal ha-1 (Ab) se evaluaron de acuerdo al diseño de muestreo del Inventario Nacional Forestal y de Suelos 2015; en cada sitio de muestreo se establecieron tres líneas de intersección planar para el muestreo de material leñoso (Ml), se recogió la hojarasca (Ho) y mantillo (Ma) en 0.09 m2. La carga total de combustibles osciló de 23.2 a 46.5 t ha-1 (p < 0.05), el Ma presentó mayor carga con el 43 %, seguido el material leñoso (Ml) y hojarasca (Ho) con el 31 y 26 %. La carga total (Ct) mostró relación con el Ma, Ho y Ml (r = 0.81 a 0.41), la Ho con Ph y Pe (r = 0.71 y -0.72). El c1h mostró relación con el Na, Ma, Pe y Dm (r = 0.72 a -0.41), el c10h evidenció correlación con el Ab, Pe y Na (r = 0.51 a 0.42). Las variables dasométricas solo explican la carga de combustible con diámetro menor o igual a 2.5 cm.

Microbial fuel cells (MFCs) represent a promising technology to generate bio-electricity and synchronously reduce wastewater pollutants. The presence of exoelectrogens in wastewater is critical for bio-electricity and pollutant reduction, but the performance of exoelectrogens at different pH levels remains unknown. This study aims to bridge this gap by offering an integrated approach to understanding the performance of exoelectrogens under varying substrate pH, particularly in bio-electricity generation and pollutant reduction in sugarbeet processing wastewater (SBWW). Three pH levels (ranging from acidic to alkaline) were studied and MFC's electricity output was measured. Later, current density, power density, and coulombic efficiency (CE) were calculated. Both pre- and post-experiment substrate samples were analysed with inductively coupled plasma (ICP). Furthermore, 16S rRNA gene analysis, DNA amplification, sequencing library preparation, and bioinformatics workflows on post-experiment samples of the substrate and anode samples were conducted. A diverse community of microorganisms was identified, especially Alphaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria (Geobacter). Bacteroidetes and Desulfovibrio were the major exoelectrogens responsible for electricity generation. Among the three pH levels tested, the most alkaline pH level (9.5±0.1) outperformed the others, achieving a 54% higher power density, 21% greater current density, and a 40% higher CE compared to the acidic pH level (6.5±0.1). Around 50-99% of pollutants were removed from the SBWW. The study revealed that Gammaproteobacteria thrive and perform better in alkaline environment.

Abstract: Corn drying reduces the moisture content present in the grain to levels that allow safe storage. This process requires a large amount of energy, which is why, if not applied correctly, it can affect the quality of the product to be dried, in addition to representing important costs in the operation of the drying plants. The objective of this research is to analyze the corn drying systems used in Canton Quevedo, Province of Los Ríos. In order to achieve the objective, field visits were made to the area under study, considering factors related to the technology used and the corn harvesting period, as well as, characteristics of the coastal region of Ecuador. It was determined that stationary or fixed bed drying is the drying system widely used for corn drying, which uses subsidized liquefied petroleum gas as fuel for its operation. The moisture content of the corn received at the drying plants is above 30% in the two harvesting periods of the product, a situation that has an impact on processing times and product quality. The fuel demand for drying an average mass of product of 60.2 tons, between the first harvest period, March - June, and the second period, September - November, presents a difference of 300.77 kg of LPG in relation to the first harvest, being the moisture content a key factor to take into account.

Resumen: El secado del maíz permite reducir el contenido de humedad presente en el grano a niveles que permitan un almacenamiento seguro. El objetivo de esta investigación permite analizar los sistemas de secado de maíz empleados en el Cantón Quevedo, Provincia de Los Ríos. Para alcanzar nuestro objetivo se realizaron visitas de campo en la zona objeto de estudio, por lo que se consideraron factores relacionados con la tecnología empleada y período de cosecha de maíz, características de la región costera del Ecuador. Se determinó que el secado estacionario o de lecho fijo es el sistema de secado ampliamente empleado para el secado de maíz, el cual emplea como combustible el gas licuado de petróleo subsidiado para su funcionamiento. La humedad de recibo de maíz en las plantas de secado presenta niveles de humedad por encima del 30 %, en los dos periodos de cosecha del producto, situación que repercute en los tiempos de proceso y en la calidad del producto. La demanda de combustible para secar una masa promedio de producto, 60,2 Ton, entre el primer período de cosecha que va de Marzo - Junio, y el segundo período, Septiembre - Noviembre, presenta una diferencia de 300,77 Kg de GLP con relación a la primera cosecha, siendo la humedad de recibo un factor clave a tomar en cuenta.

Abstract In recent years, the South Korean philosopher living in Germany, Byung-Chul Han, has been setting new paths for philosophical reflection using the theoretical potential that arises from the understanding of the new social, political and economic realities that mark this era of neoliberal evolution and of technological development in the context of the Fourth Industrial Revolution. Thus, topics such as the transformation of biopolitics into psycho-politics become a very relevant point for the analysis of current societies and their drifts. With this background of thought, this article aims to delve into Han’s arguments, exploring the crucial role that emotions play in societies of performance, fatigue and lack of democracy, resorting to the metaphor of the “hamster wheel” as an image evocative of the dynamics of current societies. In this way, an innovative perspective of the complexity of the 21st Century is presented by delving into certain nuances of Han’s thought in connection with the palpable reality of the emotions that act as the fuel that propels each individual in their own “existential wheel”. This articulation with emotional experiences contributes significantly to contemporary discussions about human nature in contexts of technological innovation.

Resumen En los últimos años, el filósofo surcoreano radicado en Alemania, Byung-Chul Han, viene marcando nuevos derroteros para la reflexión filosófica usando el potencial teórico que surge de la comprensión de las nuevas realidades sociales, políticas y económicas, que marcan esta época de evolución neoliberal y de desarrollo tecnológico, en el contexto de la cuarta Revolución Industrial. Así, temas como la transformación de la biopolítica en psicopolítica se convierten en un punto muy relevante para el análisis de las sociedades actuales y sus derivas. Con este trasfondo de pensamiento, el presente artículo tiene por objetivo sumergirse en las argumentaciones de Han, explorando el papel crucial que desempeñan las emociones en las sociedades del rendimiento, del cansancio y de la infocracia, acudiendo a la metáfora de la “rueda del hámster” como imagen evocadora de las dinámicas de las sociedades actuales. De esta forma, se presenta una perspectiva innovadora de la complejidad del siglo XXI, al adentrarnos en determinados matices del pensamiento de Han, en conexión con la realidad palpable de las emociones, que actúan como el combustible que impulsa a cada individuo en su propia “rueda existencial”. Esta articulación con las experiencias emocionales contribuye de manera significativa a las discusiones contemporáneas acerca de la naturaleza humana en contextos de innovación tecnológica.