Activation of violaxanthin cycle in darkness is a common response to different abiotic stresses : a case study in Pelvetia canaliculata

Background: In the violaxanthin (V) cycle, V is de-epoxidized to zeaxanthin (Z) when strong light or light combined with other stressors lead to an overexcitation of photosystems. However, plants can also suffer stress in darkness and recent reports have shown that dehydration triggers V-de-epoxidation in the absence of light. In this study, we used the highly stress-tolerant brown alga Pelvetia canaliculata as a model organism, due to its lack of lutein and its non-photochemical quenching independent of the transthylakoidal-ΔpH, to study the triggering of the V-cycle in darkness induced by abiotic stressors. Results: We have shown that besides desiccation, other factors such as immersion, anoxia and high temperature also induced V-de-epoxidation in darkness. This process was reversible once the treatments had ceased (with the exception of heat, which caused lethal damage). Irrespective of the stressor applied, the resulting de-epoxidised xanthophylls correlated with a decrease in Fv/Fm, suggesting a common function in the down-regulation of photosynthetical efficiency. The implication of the redox-state of the plastoquinone-pool and of the differential activity of V-cycle enzymes on V-de-epoxidation in darkness was also examined. Current results suggest that both violaxanthin de-epoxidase (VDE) and zeaxanthin-epoxidase (ZE) have a basal constitutive activity even in darkness, being ZE inhibited under stress. This inhibition leads to Z accumulation. Conclusion: This study demonstrates that V-cycle activity is triggered by several abiotic stressors even when they occur in an absolute absence of light, leading to a decrease in Fv/Fm. This finding provides new insights into an understanding of the regulation mechanism of the V-cycle and of its ecophysiological roles.

Tax-Based Fisheries Management: The Case Study Of The Cantabrian Anchovy Fishery

A dynamic optimisation framework is adopted to show how tax-based management systems theoretically correct the inefficient allocation of fishing resources derived from the stock externality. Optimal Pigouvian taxes on output (τ) and on inputs (γ) are calculated, compared and considered as potential alternatives to the current regulation of VIII division Cantabrian anchovy fishery. The sensibility analysis of optimal taxes illustrates an asymmetry between (τ) and (γ) when cost price ratio varies. The distributional effects also differ. Special attention will be paid to the real implementation of the tax-based systems in fisheries.

Process management in healthcare.Sant Camil Hospital case study

Nowadays due to the crisis, some government measures are aimed at reducing healthcare spending, affecting in some level or another the quality offered. Process management is said to be a useful tool for reducing healthcare costs by improving management without any additional economic investment. That is doing more with the same resources and without reducing the quality offered. In this study an empirical case of a Catalan hospital is presented. Overall, the usefulness of process management in the healthcare sector is shown and some tips are provided for those managers that want to implement this management system in their hospitals. This work is also interesting for those managers responsible for the National Healthcare System due to a big question is stated: what would happen if process management was implemented in the whole healthcare system?

Weighting social preferences in participatory multi-criteria evaluations: a case study on sustainable natural resource management

28 p.

Pertsonen-kudeaketaren kasu-azterketa: Burdiñola, S.Coop.

LABURPENA: Lan honetan Burdinola S.Coop.-ko pertsonen kudeaketa aztertuko da, giza baliabideen zuzendaritzaren ikuspuntutik, alegia. Horrela, organizazioetan giza baliabideek zenbaterainoko garrantzia daukaten erakutsi nahi da. Izan ere, alor horretan ezarritako helburu nahiz estrategiek erakundeko helburu orokorrak lortzea errazten dute. Hasteko lanean murgiltzeko balio duen sarrera labur bat, helburuak eta erabilitako metodologiaren zehaztapena egingo da. Ondoren, Burdinola kooperatiba aurkeztuko da eta segidan giza baliabideen ikuspuntutik kanpo zein barne analisia burutuko dira, azkenean AMIA matrize batean ideiak islatuz. Ildo beretik, giza baliabideen helburuak eta estrategiak diseinatuko dira, estrategien ikuskaritza eta ebaluazioa dakartenak loturik. Amaitzeko ondorio nagusienak planteatuko dira, erreferentzi bibliografiko eta eranskinez gain.