Implicación de genes de Pseudomonas simiae PICF7 en endofitismo, control biológico y promoción del crecimiento vegetal

The olive (Olea europaea L.) is the most emblematic tree in the Mediterranean basin, since 98% of its world´s cultivated area is found in this region. The morphological characteristics of this plant, its excellent adaptation to the typical dry and hot summers of this geographical area and the multiple uses of the cultivated and wild olive, make this tree of a huge economic, social and ecological importance. Spain leads the world´s production of olive oil and table olives. However, a/biotic factors such as the presence of pathogens and pests which are difficult to eradicate, erosion and soil loss, and the foreseeable effects of climate change are major threats to the crop. Currently, Verticillium wilt of olive (VWO), a disease caused by the hemibiotrophic fungus Verticillium dahliae Kleb. is considered one of the most devastating diseases affecting olive trees, and constitutes a limiting factor for the olive oil and table olives production. Moreover, recent studies have predicted an increase in temperature and prolonged periods of drought in the Mediterranean basin, which could lead to restrictions in the use of fresh water for irrigation, making it necessary to use saline or reclaimed water. To date, individual control measures employed against VWO have been ineffective. Consequently, integrated control methods combining preventive and palliative measures are considered the best strategy to manage the disease as well as to mitigate the spread of the causal pathogen. Within the integrated management strategy, biological control represents a sustainable and environmentally friendly approach and an alternative to the traditional chemical fungicides. Previous studies have demonstrated that Pseudomonas simiae PICF7 (formerly P. fluorescens PICF7), an indigenous inhabitant of olive roots, is an effective biological control agent (BCA) against VWO. In addition, its ability to promote growth in olive and barley, as well as in the model plant Arabidopsis thaliana, has been demonstrated. So far, strain PICF7 is perhaps the best characterized BCA against VWO. Nevertheless, the mechanisms involved in disease control and its endophytic root colonization ability in several hosts (i.e. olive, barley and wheat) remain largely unknown. Efforts to unravel the keys to the success of strain PICF7 as a BCA have even been made even by studying its interaction with other pathogens. So far, it has only been demonstrated the ability of strain PICF7 to induce systemic resistance to Botrytis cinerea in A. thaliana. Moreover, it is essential that PICF7 and V. dahliae share the same ecological niche (roots, rhizosphere) for the biocontrol of VWO, since an effective suppression of this pathogen has not been observed when both BCA and fungus are spatially separated ("split-root" system). Similarly, no disease control was observed when the phytopathogenic bacterium Pseudomonas savastanoi pv. savastanoi (causal agent of olive knot disease) and PICF7 were inoculated in different parts of the plant (BCA in the roots and pathogen in the stem). However, it was detected a transient reduction of the pathogen population and changes in the morphology of the associated tumors were detected when both microorganisms were applied to the same point (stem). Previous work has also shown that colonization of olive and banana roots by the strain PICF7 results in changes in the expression of genes involved in defensive responses, both locally (roots) and systemically (aerial part). Finally, it has been studied whether bacterial phenotypes traditionally associated with biological control and root colonization (e.g. siderophore production or motility) could be involved in VWO control. Interestingly, the results showed that PICF7 mutants altered in these phenotypes were not compromised in their ability to control the disease. In order to untangle the molecular and genetic bases underlying the effective biocontrol of VWO exerted by strain PICF7, as well as its ability to endophytically colonize olive roots, the present Thesis evaluated the possible contribution of three new phenotypes: 1) biofilm formation, which is traditionally associated with colonization and endophytism; 2) copper tolerance, a metal present in most commercial agricultural antifungals, which could contribute to greater adaptation and survival in soils; and 3) production of phytase, an enzyme involved in phosphorus mobilization and bioavailability, thus promoting plant growth. For this purpose, more than 5.500 Tn5-TcR (Tetracycline-resistance) insertion mutants (transposants) of a pre-existing random transposon insertion mutant bank were screened. Subsequently, for the identification of the Tn5-TcR insertion sites and, consequently, of the altered genes in the selected transposants, nested PCR was used. Finally, the mutants designated as Bfm8 and Bfm9 (unable to form biofilms), Cop1 and Cop33 (altered in copper tolerance) and Phy17 and Phy18 (deficient in phytase activity) were selected to carry out the olive root colonization and VWO biocontrol assays. By using confocal microscopy, it has been shown that all mutants affected in the aforementioned phenotypes were able to superficially colonize olive roots, although analysis of longitudinal sections of these roots revealed that mutants defective in biofilm formation (Bfm8 and Bfm9) did not colonize them internally. None of the studied phenotypes seemed to be involved in the biocontrol ability of PICF7 against VWO, since all selected mutants behaved similar to the wild-type strain PICF7, even though phytase defective mutants (Phy17 and Phy18) were impaired in their ability to antagonize V. dahliae in in vitro assays on one of the culture media used. This fact highlights the importance of contrasting in vitro observations with in planta assays, where the olive-Verticillium-BCA tripartite interaction becomes more complex. This is because there are numerous interactions with and among the remaining plant´s microbiota, as well as with several environmental and pedological factors. Pseudomonas sp. strain PICF6, another effective BCA against VWO, was included in some experiments performed in this Thesis for comparative purposes in order to accomplish some of the proposed objectives. In contrast to strain PICF7, there is virtually no information concerning the control of phytopathogens or the plant growth promotion capabilities of the beneficial strain PICF6, also originating from the olive rhizosphere. To overcome this lack of knowledge, both BCA and the Bfm and Phy mutants of PICF7, were tested in in vitro experiments against several pathogens of great agroeconomic importance in different crops. Strains PICF6 and PICF7, along with all selected mutants derived from the latter, only exhibited the ability to antagonize Verticillium longisporum ELV25, despite the inhibition rates of PICF7 mutants defective in phytase activity being significantly lower. The ability of these rhizobacteria to promote plant growth and colonize oilseed rape roots, host plant of V. longisporum, was also evaluated. Although none of the strains tested promoted the growth of this plant, belonging to the Brassicaceae family, all of them were able to colonize the root surface of oilseed rape seedlings. However, no evidence of endophytic colonization was found. Production of volatile organic compounds (VOC) has been described amongst the possible mechanisms by which beneficial microorganisms are able to inhibit the growth of phytopathogens or promote plant growth. A recent study has shown that strain PICF7 is able to promote plant growth of A. thaliana, not only through direct contact between the BCA and plant roots, but also through the emission of VOC without any physical contact. Nonetheless, it is unknown whether the ability of strains PICF6 and PICF7 to reduce V. dahliae growth could be attributed to this mechanism. In this context, the characterization of PICF6 and PICF7 volatilomes, as well as of the Bfm and Phy mutants, using Gas Chromatography-Mass Spectrometry (GC-MS), allowed the identification of several compounds described in the literature for their antimicrobial potential or plant growth-promoting activity. Conversely, in vitro VOC inhibition assays, using TCVA (Two Clamp VOC Assay) methodology, showed that none of the assayed strains were able to antagonize V. dahliae. Nevertheless, the compounds identified in the volatilome of these rhizobacteria, used individually and at a higher concentration, could represent a new avenue to explore substances with antagonistic capacity against V. dahliae and other relevant pathogens, as well as to evaluate their potential for plant growth promotion. As mentioned above, drought and salinity (abiotic stresses), along with to pathogen infections (biotic stresses), constitute another major threat to olive crop. Several microorganisms have shown high potential to reduce the effects of these stresses in plants. For this reason, the present Thesis has also been focused on studying the role of Pseudomonas sp. PICF6 and P. simiae PICF7 in the alleviation of the symptoms in plants caused by water scarcity of water or by salt accumulation in the soil. Numerous studies have attributed the beneficial effect of certain rhizobacteria on plants subjected to salt or drought stress to the production of the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACD). These stresses induce the biosynthesis of ethylene (ET), a phytohormone that, among the numerous processes in which it is involved, causes a negative effect on the plant at high concentrations. ACD catalyzes the conversion of ACC, the immediate precursor of ET, into α-ketobutyrate and ammonia. Therefore, ACD-producing microorganisms contribute to reduce ET levels and, consequently, the stress caused by the accumulation of this phytohormone in the plant. Furthermore, the plant can also develop different defense strategies to mitigate the negative effects caused by this type of stress, including changes in stem water potential (Ψ) and stomatal conductance (gs), or in chlorophyll (Chl), flavonoid (Flv) or proline contents. Experiments were carried out to compare the physiological parameters mentioned above in plants inoculated with an ACD-producing rhizobacteria (Pseudomonas sp. PICF6) and in plants inoculated with a non ACD-producing rhizobacteria (P. simiae PICF7). The results obtained showed that, under the experimental conditions here used, Flv values were influenced by the presence of the bacteria. However, Ψ, gs and the Chl and proline contents remained unchanged upon inoculation of the different strains. Overall, the assayed rhizobacteria, regardless of whether or not they possess ACD activity, did not alleviate the stress produced by drought or salinity in olive plants under the experimental conditions. Finally, as a consequence of the work carried out in this section, it was also demonstrated that the colonization pattern of olive roots by Pseudomonas sp. PICF6 was similar to that observed for PICF7, including its endophytic capacity. In summary, the results obtained in this Thesis allow us to conclude that the three phenotypes of P. simiae PICF7 here examined (phytase activity, biofilm formation and copper tolerance) are not involved in the ability of this BCA to control VWO, although in the particular case of mutants altered in biofilm formation no evidence of endophytic colonization of olive roots was found. Therefore, VWO biocontrol by strain PICF7 does not seem to require inner colonization of this organ. Additinally, strains PICF6 and PICF7 did not show the ability to alleviate symptoms caused by salt or drought stress in olive plants, ruling out the involvement of the ACD activity, at least under the conditions analyzed. Colonization pattern studies for both strains showed that the two olive rhizobacteria superficially colonize the root of this model plant. However, neither PICF6 nor PICF7 promoted the growth of this plant. Yet, the characterization of PICF6 and PICF7 volatilomes allowed for the identification of several VOC with a reported antimicrobial activity. Even though the involvement of VOC in the inhibition of V. dahliae growth in vitro was not observed, the collected information could pave the way for further study of these molecules individually and against different pathogens.El olivo (Olea europaea L.) es el árbol más emblemático de la cuenca mediterránea, concentrándose en esta región el 98% de superficie cultivada de este árbol a nivel mundial. Las características morfológicas de esta planta, su excelente adaptación a los veranos secos y cálidos propios de esta área geográfica, además de los múltiples usos del olivo cultivado y silvestre, hacen que este posea una enorme importancia económica, social y ecológica. España lidera la producción mundial de aceite de oliva y aceituna de mesa. Sin embargo, factores a/bióticos como la presencia de patógenos y plagas de difícil erradicación, la erosión y pérdida de suelo o los previsibles efectos del cambio climático, suponen importantes amenazas para el cultivo. Enfermedades como la verticilosis del olivo (VO), causada por el hongo hemibiotrófico Verticillium dahliae Kleb. y considerada como una de las afecciones más devastadoras del olivo, constituyen un factor limitante para la producción de aceite de oliva y aceitunas de mesa. Asimismo, estudios recientes prevén un aumento de la temperatura y episodios prolongados de sequía en la cuenca mediterránea, lo que podría conducir a restricciones en el uso de agua dulce para irrigación, haciendo necesaria la utilización de agua salada o regenerada y comprometiendo la producción. En lo que respecta a la VO, los diferentes métodos de control de la enfermedad empleados de manera individual han sido ineficaces. Es por ello que el control integrado, combinando medidas preventivas y paliativas de diversa índole, se plantea como la mejor estrategia para manejar la enfermedad y mitigar la dispersión del patógeno que la provoca. Una de las medidas dentro de esta estrategia integrada es el control biológico, herramienta sostenible y respetuosa con el medio ambiente que surge como alternativa a los tradicionales fungicidas químicos. Estudios previos demostraron que Pseudomonas simiae PICF7 (anteriormente P. fluorescens PICF7), bacteria aislada de raíces de olivo (cultivar Picual), es un eficaz agente de control biológico (ACB) frente a la VO. Además, se ha comprobado su capacidad para promover el crecimiento en olivo y cebada, así como en la planta modelo Arabidopsis thaliana. La cepa PICF7 es quizás el ACB mejor caracterizado contra la VO, aunque los mecanismos implicados en el control de la enfermedad y en la capacidad de colonización endofítica de raíces en diversos huéspedes (olivo, cebada y trigo) continúan siendo bastante desconocidos. Las claves del éxito de la cepa PICF7 como ACB se han intentado desvelar incluso estudiando su interacción con otros patógenos. Hasta el momento solo se ha demostrado que induce resistencia sistémica frente a Botrytis cinerea en A. thaliana. Por otra parte, en el caso del control de la VO, es necesario que PICF7 y V. dahliae compartan el mismo nicho ecológico (raíces, rizosfera), pues no se ha observado un control efectivo de este patógeno cuando ACB y hongo se inoculan en raíces separadas en distintos compartimentos (sistema “split-root”). De igual manera, no se observó control cuando la bacteria fitopatógena Pseudomonas savastanoi pv. savastanoi (agente causal de la tuberculosis del olivo) y PICF7 se inoculaban en órganos diferentes de la planta (ACB en las raíces y patógeno en el tallo), pero sí se detectó una reducción transitoria de la población del patógeno y un cambio en la morfología de los tumores cuando ambos microorganismos eran aplicados en el mismo lugar (tallo). Trabajos anteriores también han demostrado que la colonización de las raíces de olivo y platanera por la cepa PICF7 desencadena cambios en la expresión de genes implicados en respuestas defensivas tanto a nivel local (raíces) como sistémico (parte aérea). Finalmente, se ha estudiado si fenotipos bacterianos tradicionalmente asociados con el control biológico y colonización de las raíces (p. ej., producción de sideróforos o motilidad) podían influir en el control de la VO, evidenciándose que mutantes de PICF7 alterados en estos fenotipos no veían mermada su capacidad para controlar la enfermedad. Con el objetivo de desentrañar las bases moleculares y genéticas que subyacen y explican el control efectivo de la VO ejercido por la cepa PICF7, así como su capacidad para colonizar endofíticamente raíces de olivo, en la presente Tesis se evaluó la posible contribución de tres nuevos fenotipos: 1) formación de biopelículas, fenotipo tradicionalmente asociado a colonización y endofitisimo; 2) tolerancia al cobre, metal presente en la mayoría de antifúngicos agrícolas comerciales, que podría contribuir a una mayor adaptación y supervivencia en suelos; y 3) producción de fitasa, enzima que ayuda a incrementar la movilización y disponibilidad del fósforo promoviendo el crecimiento vegetal. Para ello, se llevó a cabo el escrutinio de más de 5.500 mutantes procedentes de una mutateca preexistente generada mediante inserciones al azar del transposón Tn5-TcR, el cual confiere a los transposantes resistencia al antibiótico tetraciclina. Posteriormente, para la identificación de los lugares de inserción de Tn5-TcR y, consecuentemente, de los genes alterados en los transposantes seleccionados, se empleó la técnica de PCR anidada (“nested”-PCR). Finalmente, los mutantes denominados Bfm8 y Bfm9 (incapaces de formar biopelículas), Cop1 y Cop33 (alterados en tolerancia al cobre) y Phy17 y Phy18 (deficientes en actividad fitasa) se seleccionaron para llevar a cabo los ensayos de colonización de la raíz del olivo y biocontrol de la VO. En cuanto a colonización, el uso de microscopía confocal demostró que todos los mutantes afectados en los fenotipos mencionados fueron capaces de colonizar superficialmente las raíces de olivo, aunque el análisis de secciones longitudinales de dichas raíces reveló que los mutantes defectivos en formación de biopelículas (Bfm8 y Bfm9) no las colonizaron internamente. En lo que respecta a capacidad de biocontrol, ningún fenotipo pareció estar involucrado en esta habilidad, ya que todos los mutantes seleccionados controlaron la enfermedad al mismo nivel que la cepa parental PICF7, aun cuando los mutantes defectivos en actividad fitasa (Phy17 y Phy18) vieron mermada su capacidad de antagonizar V. dahliae in vitro en uno de los medios de cultivo empleados. Este hecho pone de manifiesto la crucial importancia de contrastar las observaciones efectuadas in vitro con los ensayos in planta, donde la interacción tripartita olivo-Verticillium-ACB se torna más compleja al entrar en juego las interacciones con y entre el resto de la microbiota de la planta, así como de diversos factores ambientales y pedológicos. La cepa Pseudomonas sp. PICF6, otro ACB eficaz frente a la VO, se incluyó en esta Tesis a efectos comparativos para abordar algunos de los objetivos planteados. Al contrario de lo que ocurre con PICF7, la información sobre esta bacteria beneficiosa originaria de la rizosfera de olivo en lo que respecta al control de fitopatógenos o a la promoción del crecimiento vegetal es prácticamente nula. Para soslayar esta deficiencia, ambos ACB, así como los mutantes Bfm y Phy de PICF7, se enfrentaron en experimentos in vitro a varios patógenos de gran importancia agroeconómica en diferentes cultivos. Las cepas PICF6 y PICF7, así como todos los mutantes derivados de esta última, sólo mostraron capacidad de antagonizar a Verticillium longisporum ELV25, aunque los índices de inhibición de los mutantes PICF7 defectivos en actividad fitasa fueron significativamente inferiores. También se evaluó la capacidad de estas rizobacterias de promover el crecimiento vegetal y de colonizar las raíces de colza, planta huésped de V. longisporum. Aunque ninguna de las cepas ensayadas promovió el crecimiento de esta brasicácea, todas fueron capaces de establecerse superficialmente sobre sus raíces. Sin embargo, no se encontró evidencia de colonización endófita. Entre los posibles mecanismos por los cuales microorganismos beneficiosos son capaces de inhibir el crecimiento de fitopatógenos o promover el crecimiento de las plantas se ha descrito la producción de compuestos orgánicos volátiles (COV). Un estudio reciente ha demostrado que la cepa PICF7 es capaz de promover el crecimiento vegetal de A. thaliana, no solo a través del contacto directo entre el ACB y las raíces de la planta, sino también a través de la emisión de COV sin mediar contacto físico. Sin embargo, se ignora si la capacidad de las cepas PICF6 y PICF7 para reducir el crecimiento de V. dahliae podría deberse a este mecanismo. La caracterización del volatiloma de las rizobacterias PICF6 y PICF7, así como de los mutantes Bfm y Phy de esta última, mediante el uso de Cromatografía de Gases-Espectrometría de Masas (GC-MS), permitió identificar numerosos compuestos descritos en la bibliografía por su potencial actividad antimicrobiana o promotora del crecimiento vegetal. Aun así, los ensayos de inhibición in vitro por COV, en los que se usó la metodología TCVA (de sus siglas en inglés “Two Clamp VOC Assay”), mostraron que ninguna de las cepas analizadas era capaz de antagonizar frente V. dahliae. A pesar de todo, los compuestos identificados en el volatiloma de estas rizobacterias, usados de forma individual y a una concentración mayor, podrían suponer una nueva vía para explorar sustancias con poder antagonista frente a V. dahliae y otros patógenos relevantes, así como para evaluar su potencial en la promoción del crecimiento de plantas. Como se menc

Constructing tasks for primary teacher education from the perspective of Mathematics Teachers’ Specialised Knowledge

International audienceDeveloping tasks to help prospective teachers construct professional knowledge is an under-researched area of teacher education. In this paper we focus on describing the process of generating tasks in a research project at the University of Huelva. Using the model Mathematics Teachers’ Specialized Knowledge we designed tasks to prompt the construction of specific elements of knowledge necessary for teaching mathematics, with the involvement of educators and prospective teachers selected ad hoc. As an example, we describe elements from a task focused on the notion of a polygon

A Novel Real-Time MATLAB/Simulink/LEGO EV3 Platform for Academic Use in Robotics and Computer Science

Over the last years, mobile robot platforms are having a key role in education worldwide. Among others, LEGO Robots and MATLAB/Simulink are being used mainly in universities to improve the teaching experience. Most LEGO systems used in the literature are based on NXT, as the EV3 version is relatively recent. In contrast to the previous versions, the EV3 allows the development of real-time applications for teaching a wide variety of subjects as well as conducting research experiments. The goal of the research presented in this paper was to develop and validate a novel real-time educational platform based on the MATLAB/Simulink package and the LEGO EV3 brick for academic use in the fields of robotics and computer science. The proposed framework is tested here in different university teaching situations and several case studies are presented in the form of interactive projects developed by students. Without loss of generality, the platform is used for testing different robot path planning algorithms. Classical algorithms like rapidly-exploring random trees or artificial potential fields, developed by robotics researchers, are tested by bachelor students, since the code is freely available on the Internet. Furthermore, recent path planning algorithms developed by the authors are also tested in the platform with the aim of detecting the limits of its applicability. The restrictions and advantages of the proposed platform are discussed in order to enlighten future educational applications

Participation in Everyday Activities of Children with and without Neurodevelopmental Disorders: A Cross-Sectional Study in Spain

[Abstract] Children with neurodevelopmental disorders (NDDs) often report significant difficulties performing activities of daily living (ADLs), which may restrict their daily participation. The aim of this study was to investigate the differences in ADLs participation between children with NDDs and typically developing (TD) children, and to explore the associations between different daily participation contexts. A cross-sectional study was conducted that included twenty children with a medical diagnosis of an NDD and 26 sex- and age-matched TD controls. The daily participation across home, community, school, and instrumental living activities was measured using the Child and Adolescent Scale of Participation (CASP). The results show that children with NDDs engaged in lower participation in all CASP contexts (Δ = 1.7–5.5, p < 0.001) and had a significantly higher prevalence of moderate or severe restricted participation than their TD peers (OR = 23.4, 95% CI = 3.6–154.2, p < 0.001). Additionally, a strong association was found between the different contexts of participation (r = 0.642–0.856). Overall, the children with NDDs experienced significant participation restrictions on their daily activities. This study adds to the growing evidence showing that intervention strategies in this population should adopt a participation-oriented approach

Un experimento de enseñanza en formación continua estructurado por el modelo MTSK

La formación de maestros ya egresados es un área infraexplorada en la investigación en Educación Matemática, especialmente en relación con su conocimiento. Presentamos aquí los resultados de un experimento de enseñanza orientado a la formación de maestros egresados. Este experimento tuvo lugar en la Universidad de Huelva con un total de 39 maestros, en el contexto de un curso de adaptación al Grado de Primaria. Para la fundamentación teórica del experimento usamos el modelo de Conocimiento Especializado del Profesor de Matemáticas, que permitió a su vez generar una hipótesis de progresión de aprendizaje. Mostraremos tanto el diseño del experimento, como el análisis retrospectivo del mismo. Los resultados del estudio evidenciaron que los maestros mejoran en el uso de su conocimiento de los temas, y de la enseñanza de las matemáticas

El conocimiento especializado del profesor de matemáticas detectado en la resolución del problema de las cuerdas

En este documento mostramos un análisis sobre el conocimiento que evidencia un profesor de matemáticas de secundaria al resolver el problema de las cuerdas (se colocan n puntos sobre una circunferencia, ¿es posible determinar el número de todas las cuerdas que pueden trazarse?), usando el modelo analítico de conocimiento profesional mathematics teacher’s specialised knowledge (MTSK). Los resultados muestran la potencialidad del modelo como herramienta de análisis para profundizar en la comprensión y caracterización del conocimiento del profesor de matemáticas, en particular del conocimiento de los temas

Conocimiento especializado del profesor de matemáticas (MTSK): un modelo analítico para el estudio del conocimiento del profesor de matemáticas

Desde nuestra perspectiva de considerar la Didáctica de la Matemática como una aplicación de las matemáticas y en la búsqueda de significado de un conocimiento profundo de la matemática elemental, nuestra investigación ha pretendido identificar qué necesita conocer un profesor de matemáticas para llevar a sus alumnos a razonar, argumentar, conjeturar, refutar, representar, modelizar y hacer un uso con significado del conocimiento matemático. En ese sentido, este artículo mostrará cómo damos respuesta a esa inquietud, mostrando los antecedentes y la génesis del Conocimiento Especializado del Profesor de Matemáticas (MTSK), a la vez que ejemplificamos la esencia analítica del modelo a través del análisis de la resolución de un problema por un alumno de primaria. Este artículo es una adaptación del trabajo presentado en el Congreso de la RSME de 2015, en Granada, dentro de la Sesión Especial de Conocimiento Profesional del Profesor de Matemáticas

On metaphors in thinking about preparing mathematics for teaching

This paper explores how different schools of thought in mathematics education think and speak about preparing mathematics for teaching by introducing and proposing certain metaphors. Among the metaphors under consideration here are the unpacking metaphor, which finds its origin in the Anglo-American school of thought of pedagogical reduction of mathematics; the elementarization metaphor, which has its origin in the German school of thought of didactic reconstruction of mathematics; and the recontextualization metaphor, which originates in the French school of thought of didactic transposition. The metaphorical language used in these schools of thought is based on different theoretical positions, orientations, and images of preparing mathematics for teaching. Although these metaphors are powerful and allow for different ways of thinking and speaking about preparing mathematics for teaching, they suggest that preparing mathematics for teaching is largely a one-sided process in the sense of an adaptation of the knowledge in question. To promote a more holistic understanding, an alternative metaphor is offered: preparing mathematics for teaching as ecological engineering. By using the ecological engineering metaphor, the preparation of mathematics for teaching is presented as a two-sided process that involves both the adaptation of knowledge and the modification of its environment

Una perspectiva del conocimiento matemático para la enseñanza del profesor centrada en su especialización: El modelo MTSK

Esta comunicación toma como eje de discusión la especificidad del conocimiento del profesor de matemáticas plasmada en modelos analíticos. Fruto de esta reflexión y de la búsqueda de instrumentos teóricos que nos permitieran analizar dicho conocimiento, elaboramos un modelo al que denominamos Mathematics Teacher’s Specialised Knowledge (MTSK) que considera la especialización en el conocimiento del profesor como característica definitoria. Ayudados de ejemplos, discutiremos cómo visualizamos esta especificidad y presentaremos brevemente el MTSK como un resultado del trabajo teórico y empírico que ha llevado a cabo el grupo de investigación de didáctica de la matemática en la Universidad de Huelva, España

Social services for neurodegenerative patients and their families

Introduction: Neurodegenerative diseases (ND) are the most important cause of dependency in the world. The care of these patients is mostly assumed by their families. As a result, their family quality of life (FQoL) may be affected, decreasing their well-being, and modifying their habits and normal functioning. FQoL is a multidimensional concept, composed of different aspects that determine the life situation of each family, being these components both objective and subjective. Thus, the FQoL will depend on being able to access to support services that respond to the individual needs of all members and that this is adequate to adapt the environment and lifestyle to the demands of the disease. Public administrations are responsible for covering the socio-health support needs of people with ND and their families. Objective: The objective of this research is to analyse whether the currently available social services are in accordance with the Family Life Quality model. Method: A descriptive analysis of the support offered by the public services of the Autonomous Community of Castilla y León (Spain) to people with ND and their families has been carried out, analysing its correspondence with the dimensions of the Quality of Family Life Survey of Brown and collaborators (2006): health of the family, financial well-being, family relationships, informal support, support from care services, the influence of values, leisure and community interaction. Results: The research results suggest that 1) most public services are aimed exclusively at the care of the person with ND; 2) these supports address the needs of the financial well-being, family relations and community interaction dimensions; 3) these are mainly aimed at supporting the situation when the illness worsens; 4) the limited specific services for families support them in the enjoyment of leisure and financial well-being. Conclusion: The public welfare system of Castilla y León does not consider the family of people with ND as the target of its support services, but the person with ND declared as a dependent. Thus, it does not offer support services aimed at satisfying some needs linked to the dimensions of the FQoL model. References: Brown, I., Brown, R. I., Baum, N. T., Isaacs, B., J., Myerscough, T., Wang, M. (2006). Family Quality of Life Survey: Main caregivers of people with intellectual disabilities. Surrey Place Centre