Fire regime: history and definition of a key concept in disturbance ecology

"Fire regime” has become, in recent decades, a key concept in many scientific domains. In spite of its wide spread use, the concept still lacks a clear and wide established definition. Many believe that it was first discussed in a famous report on national park management in the United States, and that it may be simply defined as a selection of a few measurable parameters that summarize the fire occurrence patterns in an area. This view has been uncritically perpetuated in the scientific community in the last decades. In this paper we attempt a historical reconstruction of the origin, the evolution and the current meaning of "fire regime” as a concept. Its roots go back to the 19th century in France and to the first half of the 20th century in French African colonies. The "fire regime” concept took time to evolve and pass from French into English usage and thus to the whole scientific community. This coincided with a paradigm shift in the early 1960s in the United States, where a favourable cultural, social and scientific climate led to the natural role of fires as a major disturbance in ecosystem dynamics becoming fully acknowledged. Today the concept of "fire regime” refers to a collection of several fire-related parameters that may be organized, assembled and used in different ways according to the needs of the users. A structure for the most relevant categories of parameters is proposed, aiming to contribute to a unified concept of "fire regime” that can reconcile the physical nature of fire with the socio-ecological context within which it occur

¿Qué podemos aprender hoy de experimentar con el diálogo socrático intentando duplicar el área de un cuadrado?

Hace dos mil cuatrocientos años Sócrates dió una extraordinaria clase de geometría, tal vez la primera con un registro detallado de un método pedagógico en vivo. Sócrates le hizo al esclavo de Menon 50 preguntas que requerían solamente sumas y multiplicaciones. Al final de la lección el estudiante descubrió por si solo cómo hacer para duplicar el área de un cuadrado. Nosotros estudiamos empíricamente la reproducibilidad de este diálogo en adultos y adolescentes del siglo XXI. Nuestros resultados muestran una notable coincidencia entre el diálogo socrático y el empírico, inclusive en aquellas preguntas donde el esclavo responde incorrectamente. Muchos de estos errores se relacionan con la 'linealidad' del pensamiento. (Por ejemplo: si quiero duplicar el área, duplico el lado) Además nuestros resultados muestran que el diálogo socrático es construido sobre una fuerte intuición del conocimiento humano y el razonamiento que persiste más de 24 siglos después de su concepción. Al mismo tiempo, también enfatiza su fracaso escolar. Después de seguir todas las preguntas casi el 50% de los participantes no pudo obtener la generalización más simple cuando se le preguntó por duplicar el área de un cuadrado de tamaño diferente, lo que nos lleva a repensar ¿qué es aprender algo

Haciendo matemática: aprender probabilidades jugando torneos con dados a piedra, papel o tijera

Consideramos que el aprendizaje de la matemática debe ser a través del camino de la exploración, la formulación de preguntas y la discusión de soluciones. Para esto proponemos trabajar con la metodología que se denomina fenómeno-concepto-terminología, Gellon et al (2005). Primero observamos y nos familiarizamos con el fenómeno, luego al entender cómo funciona adquirimos el concepto y finalmente le ponemos nombre. En esta línea será la actividad que proponemos para este taller como un ejemplo de cómo llevar efectivamente esta metodología al aula. La idea es proponer el siguiente juego: los alumnos jugarán torneos de “piedra, papel o tijera” con dados. Ellos se armarán sus propios dados eligiendo el poliedro que más les guste y qué tendrá en cada cara. En esta actividad se espera que surjan naturalmente conceptos relacionados con el cálculo de probabilidades, con la independencia de los sucesos, de probabilidades conjuntas, de probabilidades condicionales, esperanzas. Se espera que la propuesta tenga tres etapas: la primera en la cual los docentes tendrán el rol de alumnos en la actividad propuesta, la segunda en la cual se debatirán posibles escenarios de la misma y la tercera en la cual se hará una reflexión acerca de la propuesta didáctica en general

Forest fire causes and motivations in the Southern and South-Eastern Europe through experts' perception and applications to current policies

Forest fires causes and motivations are poorly understood in southern and south-eastern Europe. This research aims to identify how experts perceive the different causes of forest fires as defined in the classification proposed by the European Commission in 2013. A panel of experts (N = 271) was gathered from the EU Southern Member States (France, Greece, Italy, Portugal, and Spain) and from Central (Switzerland) and south-eastern Europe (Croatia, Serbia, Bosnia and Herzegovina, Republic of North Macedonia, and Turkey). Experts were asked to answer a questionnaire to score the importance of the 29 fire causes using a five point (1-5) Likert Scale. Agricultural burnings received the highest score, followed by Deliberate fire for profit, and Vegetation management. Most of the events stem from Negligence, whereas malicious fire setting is arguably overestimated although there are differences among the countries. This research demonstrates the importance of different techniques to enhance the knowledge of the causes of the complex anthropogenic phenomenon of forest fire occurrenc

On the role of continuing currents in lightning-induced fire ignition

Lightning flashes are an important source of wildfires worldwide, contributing to the emission of trace gases to the atmosphere. Based on experiments and field observation, continuing cur rents in lightning have since a long time been proposed to play a significant role in the ignition of wildfires. However, simultaneous detections of optical and radio signals from fire-igniting lightning confirming the role of continuing currents in igniting wildfires are rare. In this work, we first analyze the optical signal of the lightning-ignited wildfires reported by the Geostationary Lightning Mapper over the Contiguous United States (CONUS) during the summer of 2018, and we then analyze the optical and the Extremely Low Frequency signal of a confirmed fire-igniting lightning flash in the Swiss Alps. Despite data uncertainties, we found that the probability of ignition of a lightning flash with Continuing Current (CC) lasting more than 10 ms is higher than that of cloud-to-ground lightning in CONUS. Finally, we confirm the existence of a long continuing current (lasting about 400 ms) associated with a long-lasting optical signal (lasting between 2 and 4 s) of a video-recorded fire-igniting lightning flash

Lenalidomide-based induction and maintenance in elderly newly diagnosed multiple myeloma patients: updated results of the EMN01 randomized trial

In the EMN01 trial, the addition of an alkylator (melphalan or cyclophosphamide) to lenalidomide-steroid induction has been prospectively evaluated in transplant-ineligible multiple myeloma patients. After induction, patients were randomly assigned to maintenance treatment with lenalidomide alone or with prednisone continuously. This analysis (median follow-up of 71 months) focused on maintenance treatment and on subgroup analyses according to the International Myeloma Working Group Frailty Score. 217 patients in lenalidomide-dexamethasone, 217 in melphalan-prednisone-lenalidomide and 220 in cyclophosphamide-prednisone-lenalidomide arms were evaluable. 284 (43%) patients were fit, 205 (31%) intermediate-fit and 165 (25%) frail. After induction, 402 patients were eligible for maintenance, (lenalidomide arm: 204; lenalidomide-prednisone: 198). After a median duration of maintenance of 22.0 months, progression-free survival from start of maintenance was 22.2 months with lenalidomide-prednisone vs 18.6 months with lenalidomide (HR 0.85,p=0.14), with no differences across frailty subgroups. The most frequent grade ≥3 toxicity was neutropenia (10% of lenalidomide-prednisone and 21% of lenalidomide patients; p=0.001). Grade ≥3 non-hematologic adverse events were rare (<15%). In fit patients, melphalan-prednisone-lenalidomide significantly prolonged progression-free survival compared to cyclophosphamide-prednisone-lenalidomide (HR 0.72,p=0.05) and lenalidomide-dexamethasone (HR 0.72, p=0.04). Likewise, a trend towards a better overall survival was noted for melphalan-prednisone-lenalidomide and cyclophosphamide-prednisone-lenalidomide, as compared to lenalidomide-dexamethasone. No differences were observed in intermediate-fit and frail patients. This analysis showed positive outcomes of maintenance with lenalidomide-based regimens, with a good safety profile. For the first time, we showed that fit patients benefit from a triplet full-dose regimen, while intermediate-fit and frail patients from gentler regimens. ClinicalTrials.gov registration number: NCT01093196

Extending the temporal context of ethnobotanical databases: the case study of the Campania region (southern Italy)

<p>Abstract</p> <p>Background</p> <p>Ethnobotanical studies generally describe the traditional knowledge of a territory according to a "hic et nunc" principle. The need of approaching this field also embedding historical data has been frequently acknowledged. With their long history of civilization some regions of the Mediterranean basin seem to be particularly suited for an historical approach to be adopted. Campania, a region of southern Italy, has been selected for a database implementation containing present and past information on plant uses.</p> <p>Methods</p> <p>A relational database has been built on the basis of information gathered from different historical sources, including diaries, travel accounts, and treatises on medicinal plants, written by explorers, botanists, physicians, who travelled in Campania during the last three centuries. Moreover, ethnobotanical uses described in historical herbal collections and in Ancient and Medieval texts from the Mediterranean Region have been included in the database.</p> <p>Results</p> <p>1672 different uses, ranging from medicinal, to alimentary, ceremonial, veterinary, have been recorded for 474 species listed in the data base. Information is not uniformly spread over the Campanian territory; Sannio being the most studied geographical area and Cilento the least one. About 50 plants have been continuously used in the last three centuries in the cure of the same affections. A comparison with the uses reported for the same species in Ancient treatises shows that the origin of present ethnomedicine from old learned medical doctrines needs a case-by-case confirmation.</p> <p>Conclusion</p> <p>The database is flexible enough to represent a useful tool for researchers who need to store and compare present and previous ethnobotanical uses from Mediterranean Countries.</p