14 research outputs found
Male Meiosis as a Biomarker for Endo- to Ecodormancy Transition in Apricot
Dormancy is an adaptive strategy in plants to survive under unfavorable climatic conditions during winter. In temperate regions, most fruit trees need exposure to a certain period of low temperatures to overcome endodormancy. After endodormancy release, exposure to warm temperatures is needed to flower (ecodormancy). Chilling and heat requirements are genetically determined and, therefore, are specific for each species and cultivar. The lack of sufficient winter chilling can cause failures in flowering and fruiting, thereby compromising yield. Thus, the knowledge of the chilling and heat requirements is essential to optimize cultivar selection for different edaphoclimatic conditions. However, the lack of phenological or biological markers linked to the dormant and forcing periods makes it difficult to establish the end of endodormancy. This has led to indirect estimates that are usually not valid in different agroclimatic conditions. The increasing number of milder winters caused by climatic change and the continuous release of new cultivars emphasize the necessity of a proper biological marker linked to the endo- to ecodormancy transition for an accurate estimation of the agroclimatic requirements (AR) of each cultivar. In this work, male meiosis is evaluated as a biomarker to determine endodormancy release and to estimate both chilling and heat requirements in apricot. For this purpose, pollen development was characterized histochemically in 20 cultivars over 8 years, and the developmental stages were related to dormancy. Results were compared to three approaches that indirectly estimate the breaking of dormancy: an experimental methodology by evaluating bud growth in shoots collected periodically throughout the winter months and transferred to forcing chambers over 3 years, and two statistical approaches that relate seasonal temperatures and blooming dates in a series of 11–20 years by correlation and partial least square regression. The results disclose that male meiosis is a possible biomarker to determine the end of endodormancy and estimate AR in apricot. Copyright © 2022 Herrera, Lora, Fadón, Hedhly, Alonso, Hormaza and Rodrigo
Cigarette smoke induces pulmonary arterial dysfunction through an imbalance in the redox status of the soluble guanylyl cyclase
Chronic obstructive pulmonary disease (COPD), whose main risk factor is cigarette smoking (CS), is one of the most common diseases globally. Some COPD patients also develop pulmonary hypertension (PH), a severe complication that leads to premature death. Evidence suggests reactive oxygen species (ROS) involvement in COPD and PH, especially regarding pulmonary artery smooth muscle cells (PASMC) dysfunction. However, the effects of CS-driven oxidative stress on the pulmonary vasculature are not completely understood. Herein we provide evidence on the effects of CS extract (CSE) exposure on PASMC regarding ROS production, antioxidant response and its consequences on vascular tone dysregulation. Our results indicate that CSE exposure promotes mitochondrial fission, mitochondrial membrane depolarization and increased mitochondrial superoxide levels. However, this superoxide increase did not parallel a counterbalancing antioxidant response in human pulmonary artery (PA) cells. Interestingly, the mitochondrial superoxide scavenger mitoTEMPO reduced mitochondrial fission and membrane potential depolarization caused by CSE. As we have previously shown, CSE reduces PA vasoconstriction and vasodilation. In this respect, mitoTEMPO prevented the impaired nitric oxide-mediated vasodilation, while vasoconstriction remained reduced. Finally, we observed a CSE-driven downregulation of the Cyb5R3 enzyme, which prevents soluble guanylyl cyclase oxidation in PASMC. This might explain the CSE-mediated decrease in PA vasodilation. These results provide evidence that there might be a connection between mitochondrial ROS and altered vasodilation responses in PH secondary to COPD, and strongly support the potential of antioxidant strategies specifically targeting mitochondria as a new therapy for these diseasesThe Spanish Ministerio de Ciencia e Innovacion, ´ Programa Retos en
Investigacion ´ (grant number PID2019-104406RB-100) to MJC provided
the financial support for the conduct of the research included in this
manuscript. Garantia Juvenil program from Comunidad de Madrid
contributed with the research assistant contract to M-R,
Sistemas de cómputo de altas prestaciones con alta disponibilidad: evaluación de la performance en diferentes configuraciones
La Computación de Altas Prestaciones a través de clusters de computadores basados en Workstation y redes convencionales, posibilitó la construcción y uso de computadores paralelos. En las arquitecturas paralelas el objetivo principal es el aumento de prestaciones, utilizando el potencial ofrecido por gran número de procesadores.
La construcción de un cluster tiene tres retos: Alto Rendimiento, Alta Disponibilidad y Alta Productividad. Manejar eficientemente un número elevado de computadores en ambientes heterogéneos no es trivial, por ello requiere un cuidadoso diseño de la arquitectura y funcionalidad. Respecto a la alta disponibilidad, debemos considerar la probabilidad de los fallos o desconexión de nodos, reduciendo el tiempo medio entre fallos del computador paralelo como un todo.
Este proyecto pretende definir la configuración adecuada de tolerancia a fallos para diferentes tipos de aplicaciones, teniendo en cuenta los requerimientos de rendimiento y prestaciones del usuario, definir y validar un modelo genérico de aplicación-prestación-tolerancia a fallos.Eje: Procesamiento Distribuido y ParaleloRed de Universidades con Carreras en Informática (RedUNCI
Sistemas de cómputo de altas prestaciones con alta disponibilidad: evaluación de la performance en diferentes configuraciones
La Computación de Altas Prestaciones a través de clusters de computadores basados en Workstation y redes convencionales, posibilitó la construcción y uso de computadores paralelos. En las arquitecturas paralelas el objetivo principal es el aumento de prestaciones, utilizando el potencial ofrecido por gran número de procesadores.
La construcción de un cluster tiene tres retos: Alto Rendimiento, Alta Disponibilidad y Alta Productividad. Manejar eficientemente un número elevado de computadores en ambientes heterogéneos no es trivial, por ello requiere un cuidadoso diseño de la arquitectura y funcionalidad. Respecto a la alta disponibilidad, debemos considerar la probabilidad de los fallos o desconexión de nodos, reduciendo el tiempo medio entre fallos del computador paralelo como un todo.
Este proyecto pretende definir la configuración adecuada de tolerancia a fallos para diferentes tipos de aplicaciones, teniendo en cuenta los requerimientos de rendimiento y prestaciones del usuario, definir y validar un modelo genérico de aplicación-prestación-tolerancia a fallos.Eje: Procesamiento Distribuido y ParaleloRed de Universidades con Carreras en Informática (RedUNCI
Gestión dinámica de aplicaciones master-worker sobre sistemas distribuidos
Las aplicaciones paralelas que obedecen al paradigma ntaster-worker necesitan de políticas de gestión con objeto de maximizar el rendimiento de la aplicación a la vez que se hace un uso eficiente de Los recursos de cómputo. En este trabajo proponemos una política simple que es capaz de realizar la gestión dinámicamente de aplicaciones master-worker a partir de la información que se obtiene en tiempo real sobre la misma. La política es capaz de qjustar el número de procesadores utilizados por La aplicación con objeto de mejorar la eficiencia en el uso de recursos sin penalizar excesivamente el tiempo de ejecución final. La bondad de la política ha sido comprobada mediante un extenso conjunto de simulaciones donde se consideraron múltiples factores para modelar el comportamiento de las aplicaciones master-worker. Describimos también los resultados obtenidos por un primer prototipo de la política ejecutado sobre un conjunto homogéneo de estaciones de trabc~jo que usaban el sistema Condor como gestor de recursosI Workshop de Procesamiento Distribuido y Paralelo (WPDP)Red de Universidades con Carreras en Informática (RedUNCI
Is there a specific stage to rest? Morphological changes in flower primordia in relation to endodormancy in sweet cherry (Prunus avium L.)
24 Pags.- 8 Figs. The definitive version is available at: https://link.springer.com/journal/468In temperate woody deciduous perennials, dormancy is a survival strategy to persist winter temperatures; but chilling is also required for the release of flower bud dormancy and for the completion of flower development. This was noticed over 100 years ago, but the biological mechanisms underlying cold regulated dormancy and its release remain poorly understood. That chilling is required for the completion of flower development led us to hypothesize that a particular stage of flower development may be consistently associated with the dormant phase of flower bud development. Flower development of five sweet cherry cultivars was examined weekly under stereoscopic and optical microscopes over 3 years. Chilling requirements for each cultivar were determined by placing weekly shoots in forcing conditions. The establishment of a flower developmental scale showed that early and late flower development, in the autumn and spring, were asynchronous among cultivars and years. However, in all circumstances, dormancy occurred at the same stage of flower development, characterized by the presence of all flower whorls, with the anthers clearly differentiated in the four locules, and the pistil showing an incipient ovary, style and stigma. The length of time flower buds remained at this stage differed between cultivars and was related to their chilling requirements and date of flowering. The observation that a particular stage of flower development, common to the five cultivars examined, exists during the combined rest period provides a framework for further studies on the physiology and cellular biology of dormancy.This work was supported by the Ministerio de Economía y Competitividad—European Regional Development Fund, European Union (Grant Numbers AGL2012-40239, BES-2010–037992 to EF); Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (Grant Numbers RFP2015-00015-00, RTA2014-00085-00, RTA2017-00003-00); and Gobierno de Aragón—European Social Fund, European Union (Grupo Consolidado A12_17R).Peer reviewe
Is there a specific stage to rest? Morphological changes in flower primordia in relation to endodormancy in sweet cherry (Prunus avium L.)
Yield potential definition of the chilling requirement reveals likely underestimation of the risk of climate change on winter chill accumulation.
-90%. Regional suitability across the landscape was highly dependent on the method used to define chilling requirements, and differences were found for both cold and mild winter areas. Our results suggest that bud break percentage levels used in the assessment of chilling requirements for sweet cherry influence production risks of current and future production areas. The use of traditional methods to determine chilling requirements can result in an underestimation of productivity chilling requirements for tree crops like sweet cherry which rely on a high conversion of flowers to mature fruit to obtain profitable yields. This underestimation may have negative consequences for the fruit industry as climate change advances with climate risk underestimated