Aprendizaje basado en proyectos colaborativos. Una experiencia con estudiantes del Grado en Geografía y Ordenación del Territorio

El aprendizaje basado en proyectos colaborativos (ABPC) es una metodología educativa innovadora que facilita el aprendizaje significativo y que incrementa la relación entre teoría y práctica. En este trabajo se presenta una experiencia educativa desarrollada en la asignatura Técnicas Cualitativas del Grado en Geografía y Ordenación del Territorio. Se concluye que el ABPC se ha mostrado como una metodología que ha facilitado la obtención de las competencias de la materia y de un aprendizaje contextualizado, ha dado coherencia temática y estructura a una asignatura que por su naturaleza pudiera parecer desestructurada, ha incrementado la motivación y convertido al alumnado en el principal artífice de su proceso de aprendizaje; ha estimulado la vocación investigadora y generado sentimientos de participación y relevancia. La práctica desarrollada destaca la importancia de la tutorización, de la evaluación continua, de la coordinación docente y de la temporalización de tareas como elementos cruciales para el éxito

Pandemic Mobility/(Im)mobility in the Canary Islands: irregular migrants becoming hotel guests

In a border archipelago whose socio-economic structure is based on the specialization of tourism, mobility takes on its full significance with international tourists, labour migrants, migrants fleeing violence and poverty, lifestyle migrants, digital nomads, etc. The boundaries between these flows often become blurred, as the presence of tourists attracts labour migrants; labour and lifestyle migrants exchange roles; and irregular migrants become labour migrants. However, it has been the immobility caused by the pandemic that has turned the migration-tourism nexus on its head, transforming irregular migrants into guests of tourist establishments. Consequently, the purpose of this article is to reflect on the impact of the immobility caused by the pandemic in a territory whose raison d’être is mobility.Dans un archipel frontalier dont la structure socio-économique repose sur la spécialisation du tourisme, la mobilité prend tout son sens avec les touristes internationaux, les migrants de travail, les migrants fuyant la violence et la pauvreté, les migrants lifestyle, les nomades numériques, etc. Les frontières entre ces flux sont souvent estompées : la présence des touristes attire les travailleurs migrants ; les migrants de travail et de mode de vie échangent leurs rôles et les migrants en situation irrégulière deviennent des travailleurs migrants. Cependant, c’est l’immobilisme causé par la pandémie qui a bouleversé le lien migration-tourisme, transformant les migrants irréguliers en hôtes d’établissements touristiques. Par conséquent, l’objet de cet article est de réfléchir sur l’impact de l’immobilisme engendré par la pandémie sur un territoire dont la raison d’être est la mobilité

Nonequilibrium phase transition in a model for the propagation of innovations among economic agents

We characterize the different morphological phases that occur in a simple one-dimensional model of propagation of innovations among economic agents [X.\ Guardiola, {\it et. al.}, Phys. Rev E {\bf 66}, 026121 (2002)]. We show that the model can be regarded as a nonequilibrium surface growth model. This allows us to demonstrate the presence of a continuous roughening transition between a flat (system size independent fluctuations) and a rough phase (system size dependent fluctuations). Finite-size scaling studies at the transition strongly suggest that the dynamic critical transition does not belong to directed percolation and, in fact, critical exponents do not seem to fit in any of the known universality classes of nonequilibrium phase transitions. Finally, we present an explanation for the occurrence of the roughening transition and argue that avalanche driven dynamics is responsible for the novel critical behavior

Reducción de perturbaciones mediante molificación discreta y umbralización por wavelets

Se comparan dos técnicas para el filtrado de bioseñales: Umbralización por wavelets y Molificación Discreta. Ambas se han usado en la solución de problemas con alta sensibilidad a la presencia de ruido, especialmente en la regularización de problemas mal condicionados. El objeto es determinar qué método presenta más ventajas en bioseñales contaminadas con ruido no blanco. Se implementaron varias técnicas de umbralización: rígida y flexible (globalmente y por nivel) y estimación adaptativa (Estimador de Riesgo imparcial de Stein SURE). Las señales empleadas fueron señales electrocardiográficas (ECG) y señales de voz, con perturbaciones no blancas características de cada tipo de señal

Reducción de perturbaciones mediante molificación discreta y umbralización por wavelets

Se comparan dos técnicas para el filtrado de bioseñales: Umbralización por wavelets y Molificación Discreta. Ambas se han usado en la solución de problemas con alta sensibilidad a la presencia de ruido, especialmente en la regularización de problemas mal condicionados. El objeto es determinar qué método presenta más ventajas en bioseñales contaminadas con ruido no blanco. Se implementaron varias técnicas de umbralización: rígida y flexible (globalmente y por nivel) y estimación adaptativa (Estimador de Riesgo imparcial de Stein SURE). Las señales empleadas fueron señales electrocardiográficas (ECG) y señales de voz, con perturbaciones no blancas características de cada tipo de señal

Role of neurokinin B in the control of female puberty and Its modulation by metabolic status

[Abstract] Human genetic studies have revealed that neurokinin B (NKB) and its receptor, neurokinin-3 receptor (NK3R), are essential elements for normal reproduction; however, the precise role of NKB–NK3R signaling in the initiation of puberty remains unknown. We investigated here the regulation of Tac2 and Tacr3 mRNAs (encoding NKB and NK3R, respectively) in female rats and demonstrated that their hypothalamic expression is increased along postnatal maturation. At puberty, both genes were widely expressed throughout the brain, including the lateral hypothalamic area and the arcuate nucleus (ARC)/medial basal hypothalamus, where the expression of Tacr3 increased across pubertal transition. We showed that central administration of senktide (NK3R agonist) induced luteinizing hormone (LH) secretion in prepubertal and peripubertal females. Conversely, chronic infusion of an NK3R antagonist during puberty moderately delayed the timing of vaginal opening (VO) and tended to decrease LH levels. The expression of NKB and its receptor was sensitive to changes in metabolic status during puberty, as reflected by a reduction in Tacr3 (and, to a lesser extent, Tac2) expression in the ARC after a 48 h fast. Yet, acute LH responses to senktide in pubertal females were preserved, if not augmented, under fasting conditions, suggesting sensitization of the NKB–NK3R–gonadotropin-releasing hormone signaling pathway under metabolic distress. Moreover, repeated administration of senktide to female rats with pubertal arrest due to chronic undernutrition rescued VO (in ∼50% of animals) and potently elicited LH release. Altogether, our observations suggest that NKB–NK3R signaling plays a role in pubertal maturation and that its alterations may contribute to pubertal disorders linked to metabolic stress and negative energy balance.Ministerio de Ciencia e Innovación; BFU 2008-00984Ministerio de Ciencia e Innovación; BFU 2011-25021Andalucía. Junta, P08-CVI-0060

Depopulation impacts on ecosystem services in Mediterranean rural areas

Despite the exponential increase in human population at global scale, some rural areas have experienced a progressive abandonment over the last decades. Under particular socioecological and policy contexts, changes in demography may promote land-use changes and, consequently, alter ecosystem services (ES) supply. However, most studies on this topic have targeted urban population increase, whereas depopulation has been rarely addressed. Here, we examined how shifts in demographic variables (human population, population density, and number of villages) affect provisioning (water supply, food and biomass production) and regulating (soil retention, water and nutrient regulation) ES in Mediterranean rural areas with contrasting environmental, so-cioeconomic and land-use contexts. When depopulation results in underuse of socio-ecological systems, we ex-pected a decrease of provisioning and an increase of regulating ES, whereas we expected the opposite pattern when it results in land-use intensification. To test this hypothesis, we compared demographic data and ES estimated with Soil and Water Assessment Tool (SWAT) linked to land-use changes between the 1950s and 2000s in three rural areas of Arag ́on (NE Spain). Generalized Additive Mixed Models and Linear Mixed-Effect Models were used to analyze demographic trends, ES changes and the relationship between them. We found severe depopulation (− 42% inhabitants) and associated land-use changes in the three areas, which was particularly evident in isolated mountainous zones (− 63% inhabitants). Depopulation trends significantly affected land use and, consequently, all of the ES evaluated. In mountainous depopulated areas, land abandonment and rewilding resulted in the increase in water regulation (>1000%) and soil retention (>400%). In contrast, agriculture was intensified in more fertile and easy-to-access lowland areas, boosting the food production service (>600%). Accordingly, the interactions among depopulation, crop production and regulating ES should be considered in the management schemes and policies targeting rural areas for a balanced and sustainable supply of ES in the long term

Development and validation of a method for precise dating of female puberty in laboratory rodents: The puberty ovarian maturation score (Pub-Score)

Puberty is a key developmental event whose primary regulatory mechanisms remain poorly understood. Precise dating of puberty is crucial for experimental (preclinical) studies on its complex neuroendocrine controlling networks. In female laboratory rodents, external signs of puberty, such as vaginal opening (VO) and epithelial cell cornification (i.e., first vaginal estrus, FE), are indirectly related to the maturational state of the ovary and first ovulation, which is the unequivocal marker of puberty. Whereas in rats, VO and FE are almost simultaneous with the first ovulation, these events are not so closely associated in mice. Moreover, external signs of puberty can be uncoupled with first ovulation in both species under certain experimental conditions. We propose herein the Pubertal Ovarian Maturation Score (Pub-score), as novel, reliable method to assess peripubertal ovarian maturation in rats and mice. This method is founded on histological evaluation of pre-pubertal ovarian maturation, based on antral follicle development, and the precise timing of first ovulation, by retrospective dating of maturational and regressive changes in corpora lutea. This approach allows exact timing of puberty within a time-window of at least two weeks after VO in both species, thus facilitating the identification and precise dating of advanced or delayed puberty under various experimental conditions

Agrárpiaci Jelentések, Baromfi

Amerikai Egyesült Államok agrárminisztériumának (USDA) májusban megjelent jelentése szerint az USA csirkehústermelése 4,6 millió tonna körül alakult 2017 első negyedévében, ami 2 százalékkal haladta meg az előző év azonos időszakának kibocsátását. Az Európai Bizottság adatai alapján 2017 első 20 hetében 178 euró/100 kilogramm volt az egész csirke uniós átlagára, kismértékben csökkent az előző év hasonló időszakának átlagárához viszonyítva. Magyarországon a vágócsirke élősúlyos termelői ára (245,9 forint/kilogramm) 4,3 százalékkal volt alacsonyabb 2017 20. hetében az egy évvel korábbinál