Training hydrologists to be ecohydrologists and play a leading role in environmental problem solving

Ecohydrology is a relatively new and rapidly growing subject area in the hydrology curriculum. It is a trans-disciplinary science derived from the larger earth systems science movement and examining mutual interactions of the hydrological cycle and ecosystems. It is also an applied science focused on problem solving and providing sound guidance to catchment-scale integrated land and water resources management. The principle spheres of ecohydrology include (i) climate-soil-vegetation-groundwater interactions at the land surface with special implications for land use, food production and climate change; (ii) riparian runoff, flooding, and flow regime dynamics in river corridors with special implications for water supply, water quality, and inland fisheries; and (iii) fluvial and groundwater inputs to lakes/reservoirs, estuaries, and coastal zones with special implications for water quality and fisheries. We propose an educational vision focused on the development of professional and personal competencies to impart a depth of scientific knowledge in the theory and practice of ecohydrology and a breadth of cross-cutting knowledge and skills to enable ecohydrologists to effectively collaborate with associated scientists and communicate results to resource managers, policy-makers, and other stakeholders. In-depth knowledge in hydrology, ecology, and biogeochemistry is emphasized, as well as technical skills in data collection, modeling, and statistical analysis. Cross-cutting knowledge is framed in the context of integrated water resources management. Personal competencies to be fostered in educational programs include creative thinking, cooperation, communication, and leadership. We consider a life-long learning context but highlight the importance of master's level training in the professional formation of ecohydrologists.Facultad de Ingenierí

Retrograde semaphorin-plexin signalling drives homeostatic synaptic plasticity.

Homeostatic signalling systems ensure stable but flexible neural activity and animal behaviour. Presynaptic homeostatic plasticity is a conserved form of neuronal homeostatic signalling that is observed in organisms ranging from Drosophila to human. Defining the underlying molecular mechanisms of neuronal homeostatic signalling will be essential in order to establish clear connections to the causes and progression of neurological disease. During neural development, semaphorin-plexin signalling instructs axon guidance and neuronal morphogenesis. However, semaphorins and plexins are also expressed in the adult brain. Here we show that semaphorin 2b (Sema2b) is a target-derived signal that acts upon presynaptic plexin B (PlexB) receptors to mediate the retrograde, homeostatic control of presynaptic neurotransmitter release at the neuromuscular junction in Drosophila. Further, we show that Sema2b-PlexB signalling regulates presynaptic homeostatic plasticity through the cytoplasmic protein Mical and the oxoreductase-dependent control of presynaptic actin. We propose that semaphorin-plexin signalling is an essential platform for the stabilization of synaptic transmission throughout the developing and mature nervous system. These findings may be relevant to the aetiology and treatment of diverse neurological and psychiatric diseases that are characterized by altered or inappropriate neural function and behaviour

Forests and floods in Latin America: science, management, policy and the EPIC FORCE project

The EPIC FORCE project aimed to develop science-based policy recommendations for integrated forest and water resources management, relevant to extreme events for Costa Rica, Ecuador, Chile and Argentina. Data analysis and model application support the hypothesis that, as the size of the flood peak increases, the effect of forest cover becomes less important. Guidelines for integrated water and forest resources management are developed which recognize this effect but emphasize the role that forests play in reducing the flood levels of more moderate events. The research findings are transferred to policy-making for the four focus countries via a set of policy briefs, taking into account the institutional frameworks, achievable policy objectives and key stakeholders.Facultad de Ingenierí

Modeling Planarian Regeneration: A Primer for Reverse-Engineering the Worm

A mechanistic understanding of robust self-assembly and repair capabilities of complex systems would have enormous implications for basic evolutionary developmental biology as well as for transformative applications in regenerative biomedicine and the engineering of highly fault-tolerant cybernetic systems. Molecular biologists are working to identify the pathways underlying the remarkable regenerative abilities of model species that perfectly regenerate limbs, brains, and other complex body parts. However, a profound disconnect remains between the deluge of high-resolution genetic and protein data on pathways required for regeneration, and the desired spatial, algorithmic models that show how self-monitoring and growth control arise from the synthesis of cellular activities. This barrier to progress in the understanding of morphogenetic controls may be breached by powerful techniques from the computational sciences—using non-traditional modeling approaches to reverse-engineer systems such as planaria: flatworms with a complex bodyplan and nervous system that are able to regenerate any body part after traumatic injury. Currently, the involvement of experts from outside of molecular genetics is hampered by the specialist literature of molecular developmental biology: impactful collaborations across such different fields require that review literature be available that presents the key functional capabilities of important biological model systems while abstracting away from the often irrelevant and confusing details of specific genes and proteins. To facilitate modeling efforts by computer scientists, physicists, engineers, and mathematicians, we present a different kind of review of planarian regeneration. Focusing on the main patterning properties of this system, we review what is known about the signal exchanges that occur during regenerative repair in planaria and the cellular mechanisms that are thought to underlie them. By establishing an engineering-like style for reviews of the molecular developmental biology of biomedically important model systems, significant fresh insights and quantitative computational models will be developed by new collaborations between biology and the information sciences

El cambio climático y las condiciones ambientales en los partidos de La Plata, Berisso y Ensenada, provincia de Buenos Aires: aspectos preliminares

Se presentan las tareas iniciales realizadas en relación al proyecto Efectos del cambio climático en las condiciones ambientales de los Partidos de Berisso, Ensenada y La Plata, que es financiado por la Universidad Nacional de La Plata en el marco del programa de “Proyectos de innovación y transferencia en áreas prioritarias (PIT-AP). Con este proyecto, iniciado en 2011, se propone avanzar en el conocimiento y evaluación de la influencia que generan los cambios climáticos en las condiciones ambientales del borde sur del Río de La Plata. Estos cambios pueden producir importantes efectos en el desarrollo socioeconómico y en los riesgos a que se encuentra sometida esta región. Debido a la escasez de datos básicos y la falta de un conocimiento adecuado de las condiciones ambientales de la región, se están realizando los estudios geológicos, geomorfológicos, hidrológicos, ecológicos y topográficos necesarios para el modelado de posibles escenarios de los cambios climáticos

Modelación de la marea en el sistema lagunar de Bahía Magdalena-Almejas, B.C.S., México

Se simula numéricamente la propagación de las componentes de la marea M2, N2, S2, 1(2, 01 y un modelo numérico hidrodinámico K1 en el sistema lagunar Bahía Magdalena-Almejas, mediante barotrópico, desarrollado en diferencias finitas, centradas en el espacio y adelantadas en el tiempo. El modelo entrega, como resultados para un período de la marea, la variación superficial del nivel del mar y el campo vectorial de corrientes. Los resultados del modelo se comparan, cualitativa y cuantitativamente, con mediciones de campo de variaciones de nivel del mar y velocidad de la corriente, obteniéndose una buena concordancia entre ambas. Las velocidades máximas, registradas y modeladas en el área de estudio, ocurrieron durante el reflujo de la marea. La componente de velocidad Este fue la más importante en Boca Entrada, mientras que para la zona de canales "Canal Gaviota y Canal Rehusa", fue la Norte

Training hydrologists to be ecohydrologists and play a leading role in environmental problem solving

Ecohydrology is a relatively new and rapidly growing subject area in the hydrology curriculum. It is a trans-disciplinary science derived from the larger earth systems science movement and examining mutual interactions ofthe hydrological cycle and ecosystems. It is also an applied science focused on problem solving and providing sound guidance to catchment-scale integrated land and water resources management. The principle spheres of ecohydrology include (i) climate-soil-vegetation-groundwater interactions at the land surface with special implications for land use, food production and climate change; (ii) riparian runoff, flooding, and flow regime dynamics in river corridors with special implications for water supply, water quality, and inland fisheries; and (iii) fluvial and groundwater inputs to lakes/reservoirs, estuaries, and coastal zones with special implications for water quality and fisheries. We propose an educational vision focused on the development of professional and personal competencies to impart a depth of scientific knowledge in the theory and practice of ecohydrology and a breadth of cross-cutting knowledge and skills to enable ecohydrologists to effectively collaborate with associated scientists and communicate results to resource managers, policy-makers, and other stakeholders. In-depth knowledge in hydrology, ecology, and biogeochemistry is emphasized, as well as technical skills in data collection, modeling, and statistical analysis. Cross-cutting knowledge is framed in the context of integrated water resources management. Personal competencies to be fostered in educational programs include creative thinking, cooperation, communication, and leadership. We consider a life-long learning context but highlight the importance of master’s level training in the professional formation of ecohydrologists

Diagnostic value of a simplified Pfeiffer questionnaire for polypathological patients

Proyecto Profund.[ES]: Objetivos: Analizar la concordancia, sensibilidad, especificidad y valores predictivos positivo (VPP) y negativo (VPN) de cada pregunta del cuestionario de Pfeiffer (SPMSQ) con respecto al cuestionario completo en pacientes pluripatológicos (PPP). Métodos: Estudio transversal multicéntrico. El SPMSQ se consideró patológico si se registraban 3 o más errores. Para cada pregunta y combinaciones de 2 preguntas se calcularon la concordancia (índice kappa), sensibilidad, especificidad y valores predictivos con respecto al SPMSQ completo. Resultados: De los 1.632 pacientes pluripatológicos incluidos (edad media 77,9 ± 9,8 años, 53% varones), se realizó el SPMSQ a 1.434 (los restantes presentaban delirium) y resultó patológico en el 39%. Las preguntas «¿qué día es hoy?» y «reste de 3 en 3 desde 20» obtuvieron buena concordancia y VPN (85% y 89%, respectivamente); la combinación de ambas aumentó el VPN al 97%. La pregunta «¿cuándo nació?» alcanzó buena concordancia y el mayor VPP (93%). Conclusiones: La combinación de las preguntas «¿qué día es hoy?» y «reste de 3 en 3 desde 20» obtuvo un VPN elevado, y la relacionada con la fecha de nacimiento fue la que consiguió el mayor VPP.[EN] Objectives: To analyse the correlation, sensitivity, specificity and positive predictive (PPV) and negative predictive (NPV) values of each question on the Pfeiffer questionnaire (SPMSQ) compared with the full questionnaire for polypathological patients (PPPs). Methods: Multicentre cross-sectional study. An SPMSQ score is considered pathological if 3 or more errors are recorded. For each question and combination of 2 questions, we calculated the correlation (kappa index), sensitivity, specificity and predictive values compared with the full SPMSQ. Results: Of the 1632 PPPs included (mean age, 77.9 ± 9.8 years, 53% men), 1434 performed the SPMSQ (the remaining presented delirium); 39% of the PPPs were pathological. The question “What day is it today?” and the command “Count backwards by 3s from 20” obtained good correlation and NPV (85 and 89%, respectively); the combination of both increased the NPV to 97%. The question “When were you born?’ achieved good correlation and greater PPV (93%). Conclusions: The combination of the question “What day is it today?” and the command “Count backwards by 3s from 20” achieved a high NPV. The question related to the date of birth achieved the highest PPV