227 research outputs found
Another gun dismantled : ABSCISIC ACID INSENSITIVE4 is not a target of retrograde signaling
Article Commentary: News and Views.Peer reviewe
Reactive oxygen species in plant development
Reactive oxygen species (ROS) are produced by metabolic pathways in almost all cells. As signaling components, ROS are best known for their roles in abiotic and biotic stress-related events. However, recent studies have revealed that they are also involved in numerous processes throughout the plant life cycle, from seed development and germination, through to root, shoot and flower development. Here, we provide an overview of ROS production and signaling in the context of plant growth and development, highlighting the key functions of ROS and their interactions with plant phytohormonal networks
Optimal DG Unit Placement and Sizing in Radial Distribution Network for Power Loss Minimization and Voltage Stability Enhancement
The optimal allocation and size of decentralized generating units are essential to minimize power losses, while meeting the demand for active and reactive power in a distribution system. In other words, most of the total energy produced can be efficiently exploited by end users. In addition, if the DGs are of optimal size and location in the distribution system, the reliability, stability and efficiency of the power system are guaranteed. This paper focuses on reducing power losses and improving the voltage profile by accurately identifying the optimal location and sizing of Distributed Generation based on three indexes, namely the IVM Index Vector Method, the VDI Voltage Deviation Index and the VSI Voltage Stability Index. Two types of DGs were considered for the analysis: DGs operating with unit power factor and DGs operating with a lagging power factor. Three optimization algorithms are applied to determine the optimal sizes of decentralized generation units in a power distribution network which are GWO, WOA and PSO. The results obtained in this article show that the three algorithms give very similar values. DG at lagging power factor gives better results compared with those obtained with DGs at unity power factor. In terms of loss reduction and minimum bus voltage, the best results are obtained for the VSI index with a DG at a power factor of 0.9
Health Agency and Perfectionism:The Case of Perinatal Health Inequalities
Poor pregnancy outcomes and inequalities in these outcomes remain a major challenge, even in prosperous societies that have high-quality health care and public health policy in place. In this article, we propose that justice demands the improvement of what we call the ‘health agency’ of parents-to-be as part of a response to these poor outcomes. We take health agency to have three aspects: (i) the capacity to form health-goals one has reason to value, (ii) the control one perceives to have over achieving those health-goals and (iii) the freedom(s) one has to achieve those health-goals. We will moreover argue that this demand of justice can be best based on a perfectionist rather than neutralist method of justification. Subsequently, we will argue that perfectionist policy may be paternalistic but not wrongfully paternalistic. This leads us to conclude that perfectionism should be adopted to inform and justify public health policy that is aimed at improving health agency in general and counteracting poor pregnancy outcomes and inequalities in perinatal health outcomes in particular
The ROS wheel: refining ROS transcriptional footprints
In the last decade, microarray studies have delivered extensive inventories of transcriptome-wide changes in messenger RNA levels provoked by various types of oxidative stress in Arabidopsis (Arabidopsis thaliana). Previous cross-study comparisons indicated how different types of reactive oxygen species (ROS) and their subcellular accumulation sites are able to reshape the transcriptome in specific manners. However, these analyses often employed simplistic statistical frameworks that are not compatible with large-scale analyses. Here, we reanalyzed a total of 79 Affymetrix ATH1 microarray studies of redox homeostasis perturbation experiments. To create hierarchy in such a high number of transcriptomic data sets, all transcriptional profiles were clustered on the overlap extent of their differentially expressed transcripts. Subsequently, meta-analysis determined a single magnitude of differential expression across studies and identified common transcriptional footprints per cluster. The resulting transcriptional footprints revealed the regulation of various metabolic pathways and gene families. The RESPIRATORY BURST OXIDASE HOMOLOG F-mediated respiratory burst had a major impact and was a converging point among several studies. Conversely, the timing of the oxidative stress response was a determining factor in shaping different transcriptome footprints. Our study emphasizes the need to interpret transcriptomic data sets in a systematic context, where initial, specific stress triggers can converge to common, aspecific transcriptional changes. We believe that these refined transcriptional footprints provide a valuable resource for assessing the involvement of ROS in biological processes in plants
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