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En estos años viene reconfigurándose el paisaje político ecuatoriano. Lenín Moreno, sucesor de Rafael Correa, se acercó a los intereses empresariales y buscó desandar parte del camino «populista», al tiempo que se enfrentaba con el ex-presidente. Para ello montó una coalición político-empresarial que mantuvo diálogo con diferentes sectores. Sin embargo, la decisión de quitar los subsidios a los combustibles trajo de nuevo a escena el estallido social y a un viejo actor: el movimiento indígena ecuatoriano.

1. We live on a flammable planet yet there is little consensus on the origin and evolution of flammability in our flora. 2. We argue that part of the problem lies in the concept of flammability, which should not be viewed as a single quantitative trait or metric. Rather, we propose that flammability has three major dimensions that are not necessarily correlated: ignitability, heat release and fire spread rate. These major axes of variation are controlled by different plant traits and have differing ecological impacts during fire. 3. At the individual plant scale, these traits define three flammability strategies observed in fire-prone ecosystems: the non-flammable, the fast-flammable and the hot-flammable strategy (with low ignitability, high flame spread rate and high heat release, respectively). These strategies increase the survival or reproduction under recurrent fires, and thus, plants in fire-prone ecosystems benefit from acquiring one of them; they represent different (alternative) ways to live under recurrent fires. 4. Synthesis. This novel framework based on different flammability strategies helps us to understand variability in flammability across scales, and provides a basis for further research.

Increased wildfire frequency and size has led to a surge in flammability research, most of which investigates landscape-level patterns and wildfire dynamics. There has been a recent shift towards organism-scale mechanisms that may drive these patterns, as more studies focus on flammability of plants themselves. Here, we examine methods developed to study tissue-level flammability, comparing a novel hot-plate-based method to existing methods identified in a literature review. Based on a survey of the literature, we find that the hot plate method has advantages over alternatives when looking at the specific niche of small-to-intermediate live fuel samples—a size range not addressed in most studies. In addition, we directly compare the hot plate method to the commonly used epiradiator design by simultaneously conducting flammability tests along a moisture gradient, established with a laboratory benchtop drydown. Our design comparison addresses two basic issues: (1) the relationship between hydration and flammability and (2) relationships between flammability metrics. We conclude that the hot plate method compares well to the epiradiator method, while allowing for testing of bigger samples.

Last month's column took a light-hearted look at the complicated and serious issue of toxicity. This time around the spotlight is on the other side of the safety classification coin: flammability.

En el presente trabajo se han estudiado las percepciones y actitudes sobre la energía sostenible en un grupo de estudiantes de 2. y 4. de ESO de dos centros escolares de la Comunidad de Madrid. La herramienta para recabar la información necesaria ha consistido en un cuestionario abierto preparado a partir de la literatura. Además, con uno de los grupos se ha llevado a cabo una propuesta didáctica atractiva y dinámica basada en la columna de Winogradsky como paso previo hacia las pilas de combustible microbianas, aprovechando la declaración de 2014 como el año de la Biotecnología en España. Esta propuesta puede servir de referencia a los docentes para reforzar y extender contendos de Física, Química y Biología en el marco de una Educación Ambiental responsable y comprometida en Educación Secundaria. Transversalmente, aunque no por eso menos importante, se ha pretendido con la propuesta aumentar el interés hacia las ciencias experimentales y despertar nuevas vocaciones científicas entre los discentes.

The main process of the continued airworthiness system is put forward via collecting the events that may affect the safe operation of aircraft, carrying out engineering investigation and risk assessment, and developing corresponding corrective and improvement actions according to the causes and risks. It aims to continuously improve the safety and reliability of aircraft. According to the proposed process, the continued airworthiness event that the flammable liquid leakage drainage passage test of the aircraft pylon fails is analyzed and disposed of, which ensures the safe operation of the fleet.

In response to environmental concerns, R1234yf is used in mobile air conditioning (MAC) systems, yet it can produce trifluoroacetic acid (TFA) in water bodies, a persistent pollutant with moderate phytotoxicity and high mobility. However, R152a, an alternative, faces challenges due to its flammability (classified as A2). To address this, we propose new R152a-R13I1 mixtures (M10–M50) as R1234yf replacements in MAC units. A Simscape/MATLAB model was developed to elucidate the thermodynamic performance of an MAC unit. Theoretical estimations showed a significant reduction in burning velocity (BV) and an increase in the lower flammability limit (LFL) when R13I1 was added to R152a. For instance, at 0.20 mole fraction of R13I1, BV decreased from 23.1 to 11.3 cm s −1 ; while, LFL increased from 4.9 to 6.28 vol. %. Hence, M20 emerged as the optimal choice due to its A2L flammability classification and superior thermal properties. Simscape/MATLAB results revealed M20's 11.5–35.4% higher coefficient of performance compared to R1234yf. The model was validated against R1234yf data, showing 3.8–13.8% error. Additionally, M20's impact on MAC CO 2 emissions was evaluated, showing a potential 34.1% reduction compared to R1234yf. This highlights the environmental benefits of transitioning to R152a-R13I1 blends in MAC systems.

The description of experimental benches for combustion of demonstration elements of material samples - combustion demonstrators (CD) is given. CD for investigating thermodynamic processes during combustion on experimental benches are developed. The results of experimental studies of combustion of CD made of different materials (existing and synthesized) are presented. A new direction of research is formulated - the development of combustible materials and structures made of them, providing the specified characteristics at all stages of operation.

Pyrophytic oak landscapes across the central and eastern United States are losing dominance as shade-tolerant, fire-sensitive, or opportunistic tree species encroach into these ecosystems in the absence of periodic, low-intensity surface fires. Mesophication, a hypothesized process initiated by intentional fire exclusion by which these encroaching species progressively create conditions favorable for their own persistence at the expense of pyrophytic species, is commonly cited as causing this structural and compositional transition. However, many questions remain regarding mesophication and its role in declining oak dominance. In the present article, we review support and key knowledge gaps for the mesophication hypothesis. We then pose avenues for future research that consider which tree species and tree traits create self-perpetuating conditions and under what conditions tree-level processes might affect forest flammability at broader scales. Our goal is to promote research that can better inform restoration and conservation of oak ecosystems experiencing structural and compositional shifts across the region.