Diversity, variability and persistence elements for a non-equilibrium theory of eco-evolutionary dynamics

Natural ecosystems persist in variable environments by virtue of a suite of traits that span from the individual to the community, and from the ecological to the evolutionary scenarios. How these internal characteristics operate to allow living beings to cope with the uncertainty present in their environments is the subject matter of quantitative theoretical ecology. Under the framework of structural realism, the present dissertation project has advocated for the strategy of mathematical modeling as a strategy of abstraction. The goal is to explore if a range of natural ecosystems display the features of complex systems, and evaluate whether these features provide insights into how they persist in their current environments, and how might they cope with changing environments in the future. A suite of inverse, linear and non-linear dynamical mathematical models, including non-equilibrium catastrophe models, and structured demographic approaches is applied to five case studies of natural systems fluctuating in the long-term in diverse scenarios: phytoplankton in the global ocean, a mixotrophic plankton food web in a marine coastal environment, a wintering waterfowl community in a major Mediterranean biodiversity hot-spot, a breeding colony of a keystone avian scavenger in a mountainous environment and the shorebird community inhabiting the coast of UK. In all case studies, there is strong evidence that ecosystems are able to closely track their common environment through several strategies. For example, in global phytoplankton communities, a latitudinal gradient in the positive impact of functional diversity on community stability counteracts the increasing environmental variability with latitude. Mixotrophy, by linking several feeding strategies in a food web, internally drives community dynamics to the edge of instability while maximizing network complexity. In contrast, an externally generated major perturbation, operating through planetary climatic disruptions, induce an abrupt regime shift between alternative stable states in the wintering waterfowl community. Overall, the natural systems studied are shown to posses features of complex systems: connectivity, autonomy, emergence, non-equilibrium, non-linearity, self-organization and coevolution. In rapidly changing environments, these features are hypothesized to allow natural system to robustly respond to stress and disturbances to a large extent. At the same time, future scenarios will be probably characterized by conditions never experienced before by the studied systems. How will they respond to them, is an open question. Based on the results of this dissertation, future research directions in theoretical quantitative ecology will likely benefit from non-autonomous dynamical system approaches, where model parameters are a function of time, and from the deeper exploration of global attractors and the non-equilibriumness of dynamical systems

Structural stability of invasion graphs for generalized Lotka--Volterra systems

In this paper we study in detail the structure of the global attractor for a generalized Lotka-Volterra system with Volterra--Lyapunov stable structural matrix. We provide the full characterization of this structure and we show that it coincides with the invasion graph as recently introduced in [15]. We also study the stability of the structure with respect to the perturbation of the problem parameters. This allows us to introduce a definition of structural stability in Ecology in coherence with the classical mathematical concept where there exists a detailed geometrical structure, governing the transient and asymptotic dynamics, which is robust under perturbation.Comment: Declaration on the lack of competing interest has been adde

La edad materna como factor de riesgo obstétrico. Resultados perinatales en gestantes de edad avanzada

Producción CientíficaObjetivo Comparar los resultados perinatales de gestantes mayores de 35 años con un grupo control (< 35 años). Diseño Estudio de cohortes históricas. Lugar Valladolid (España). Método: análisis univariante y estimación de RR. Variables estudiadas relativas a la epidemiología, desarrollo del embarazo y resultados perinatales. Resultados Se analizaron 1455 partos (355 correspondientes al grupo de estudio: 24,39%). Las gestantes de mayor edad presentaron más patología asociada al embarazo (29,2 vs 15,8%, p < 0,001) como diabetes gestacional (6.2%, p < 0.0029), metrorragia del primer trimestre (5.6%, p < 0.01), y amenaza de parto prematuro (3.9%, P < 0.007). Los estados hipertensivos del embarazo aunque fueron también más frecuentes no demostraron significación estadística. Se requirió inducción médica del parto con mayor frecuencia en el grupo de estudio (RR = 1.42; CI 95%:1.08-1.87). En el 47% de las gestantes nulíparas de edad avanzada se indicó una cesárea (RR = 1.63; CI 95%: 1.24-2.15). La tasa de mortalidad perinatal en el grupo de estudio fue 16.5‰ vs 2.77‰ en el grupo control. La morbilidad materna también fue superior en el grupo de edad avanzada (RR 5.98; CI 95% 1.35-26.54), fundamentalmente por complicaciones hemorrágicas. Conclusiones la edad materna avanzada se asocia con mayor frecuencia a patología gestacional y mayor incidencia de inducciones médicas del parto y tasa de cesáreas, especialmente en nulíparas. Todo ello repercute en la morbimortalidad materna y fetal, siendo un grupo poblacional de riesgo obstétrico que requiere una atención prenatal adecuada y trasciende el ámbito de la planificación sanitaria, dado el porcentaje de gestantes de edad avanzada en nuestro medio

Effects of dietary chromium-yeast level on growth performance, blood metabolites, meat traits and muscle fatty acids profile, and microminerals content in liver and bone of lambs

To assess the effect of dietary supplement levels of chromium-yeast (Cr-yeast) on growth performance, blood glucose and triglycerides, fatty acid (FA) profile in intramuscular fat, carcase and meat traits, iron, copper, chromium and zinc concentrations in liver and bone, 24 Rambouillet male lambs (29.2 ± 0.17 kg body weight) were randomly assigned to four diets with 0, 0.2, 0.4 and 0.6mg Cr/kg DM. The growth performance trial lasted 49 d. Supplemental Cryeast did not affect growth performance and carcase characteristics (p>.05), but reduced (p<.05) perirenal and intramuscular fat, as well as 3 h post-feeding blood glucose and triglycerides concentration. In liver, Fe and Cu concentration decreased (p<.05), while Cr concentrations in liver increased with increasing Cr-yeast dietary levels. In bone, Fe decreased (p<.05) as Cryeast dietary levels increasing, and Cr-yeast supplementation increased Cr concentrations (p<.05). As Cr-yeast dietary level increased, palmitic (C16:0) and stearic (C18:0) SFA decreased linearly (p<.05), while palmitoleic (C16:1n-7), vaccenic (C18:1n-7), linoleic (C18:2n-6) and arachidic (C20:4) unsaturated fatty acids (UFA) increased linearly (p<.01). In conclusion, Cr-yeast did not affect growth performance and carcase quality, but decreased the perirenal and intramuscular fat, blood glucose and triglyceride content, and Fe and Cu concentrations in liver as increased Cr-yeast levels in the diet. Because supplemental Cr-yeast improved index of atherogenicity and unsaturated to saturated FA ratio in muscle of lambs, it could be of human nutritional interest

Revisión y evaluación de hembras caprinas y ovinas

El presente trabajo tiene por objetivo describir una serie de procedimientos que nos permita hacer una revisión, control, evaluación y selección, tanto en la majada como en el momento de la compra/trueque de ejemplares hembras.Fil: Sosa, Pablo Antonio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Catamarca; ArgentinaFil: Castro, Ornella Eugenia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Catamarca. Campo Anexo Santa Cruz; ArgentinaFil: Quinteros Dupraz, Marcelo Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Catamarca; ArgentinaFil: Brunello, Gabriela Esther. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Rioja; ArgentinaFil: Almaraz, Sabrina Cristina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Catamarca. Campo Anexo Santa Cruz; ArgentinaFil: Ojeda Fermoselle, Pablo Matias. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Catamarca. Campo Anexo Santa Cruz; Argentin

Diseño de un modelo de evaluación de seminarios de asignaturas de Derecho Civil

Memoria ID-0100. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2014-2015

Tutoría y dirección de los Trabajos de Fin de Grado en Derecho

Memoria ID-0111. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2013-2014

Mineral status and interrelationship in soil, forage, and blood serum of horses in the rainy and dry seasons

The feeding and nutrition of livestock becomes less of an empirical endeavor when the information necessary to scientifically balance diets is available [1]. Equine performance is influenced by genetic, nutritional, health, and management factors. Thus, optimal nutrition is essential for a foal to achieve maximal performance. Likewise, nutrition is fundamental for husbandry purposes as several reproductive problems due to nutritional deficiencies have been identified [2].The objective was to evaluate the content of P, Ca, Mg, K, Na, Cu, Fe, Zn, Se, and Mn in soil, forage, and serum of horses in several production units (PU) during rainy and dry seasons and predict their concentration in serum from their content in soil and forage. Soil and pastures were sampled in the dry (November–December) and in rainy seasons (June–July), and blood samples were collected from the jugular vein of 76 horses in both seasons at four PU. The experimental design was a completely random design within a 4 2 (PU season) factorial arrangement of treatments. Concentration of minerals in soil differed (P < .05) among PU, and contents of P, Ca, Mg, and K were low; Zn and Fe were high; and Cu and Mn were adequate. Mineral concentrations in forage differed among PU and season, and among PU within season (interaction P <.05). Contents of Ca, Mg, Na, Zn, and Cu were low; Fe was high; and P, K, Se, and Mn adequate. The mineral concentration in equine blood serum differed (P <.05) among PU and season. Overall, there were deficiencies of P, Ca, Mg, Na, Cu, and Se, but adequate amounts of K, Zn, and Fe. There are imbalances of minerals in soil and forages which effected their concentration inequine blood

Diseño de un modelo de evaluación de prácticas de las asignaturas de derecho

Memoria ID12-0253. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2012-2013