A root chicory MADS-box sequence and the Arabidopsis flowering repressor FLC share common features that suggest conserved function in vernalization and devernalization responses

in The Plant Journal (2013)

Root chicory (Cichorium intybus var. sativum) is a biennial crop, but is harvested for root inulin at the end of the first growing season before flowering. However, cold temperatures might vernalize seeds ... [more ▼]

Root chicory (Cichorium intybus var. sativum) is a biennial crop, but is harvested for root inulin at the end of the first growing season before flowering. However, cold temperatures might vernalize seeds or plantlets, leading to incidental early flowering and hence understanding the molecular basis of vernalization is important. A MADS-box sequence was isolated by RT-PCR and named FLC-LIKE1 (CiFL1) because of its phylogenetic positioning within the same clade as the floral repressor Arabidopsis FLOWERING LOCUS C (AtFLC). Moreover, overexpression of CiFL1 in Arabidopsis caused late flowering and prevented up-regulation of the AtFLC target FLOWERING LOCUS T gene by photoperiod, suggesting functional conservation between root chicory and Arabidopsis. Like AtFLC in Arabidopsis, CiFL1 was repressed during vernalization of seeds or plantlets of chicory, but repression of CiFL1 was unstable whether the post-vernalization temperature was favorable to flowering or whether it devernalized the plants. Instability of CiFL1 repression might be linked to bienniality of root chicory versus the annual life cycle of Arabidopsis. However, reactivation of AtFLC was also observed in Arabidopsis when a high temperature treatment was given straight after seed vernalization, erasing the promotive effect of cold on flowering. Cold-induced downregulation of a MADS-box floral repressor and its reactivation by high temperature thus appear as conserved features of the vernalization and devernalization responses in distant species.This article is protected by copyright. All rights reserved. [less ▲]

Isoform 111 of vascular endothelial growth factor (VEGF111) improves angiogenesis of ovarian tissue xenotransplantation

in Transplantation (2013), 95(3), 426-433

Background: Cryopreservation of cortex ovarian tissue before anti-cancer therapy is a promising technique for fertility preservation mainly in children and young women. Ischemia in the early stage after ... [more ▼]

Background: Cryopreservation of cortex ovarian tissue before anti-cancer therapy is a promising technique for fertility preservation mainly in children and young women. Ischemia in the early stage after ovarian graft causes massive follicle loss by apoptosis. VEGF111 is a recently described VEGF isoform that does not bind to the extracellular matrix, diffuse extensively and is resistant to proteolysis. These properties confer a significantly higher angiogenic potential to VEGF111 in comparison to the other VEGF isoforms. Methods: We evaluated the morphology of cryopreserved sheep ovarian cortex, grafted in the presence or absence of VEGF111. Ovarian cortex biopsies were embedded in type I collagen with or without VEGF111 addition before transplantation to SCID mice ovaries. Transplants were retrieved 3 days or 3 weeks later. Follicular density, vasculature network, haemoglobin content and cell proliferation were analysed. Results: Addition of VEGF111 increased density of functional capillaries (p=0.01) 3 days after grafting. By double immunostaining of Ki-67 and von Willebrand Factor (vWF) we demonstrated that proliferating endothelial cells were found in 83% of the VEGF111 group when compared to 33% in the control group (p=0.001). This angio-stimulation was associated with a significant enhancement of haemoglobin content (p=0.03). Three weeks after transplantation, the number of primary follicles was significantly higher in VEGF111 grafts (p=0.02). Conclusion: VEGF111 accelerates blood vessels recruitment, functional angiogenesis and improves the viability of ovarian cortex by limiting ischemia and ovarian cortex damage. [less ▲]

Libre prestation de services et droit d’établissement : les stratégies des entreprises

in Dubout, Edouard; Maitrot de la Motte, Alexandre (Eds.) L’unité des libertés de circulation: In varietate concordia? (2013)

Cet article examine les possibilités d'usage stratégique des libertés de circulation (liberté d'établissement et libre prestation de services) par les entreprises. Les entreprises peuvent faire usage des ... [more ▼]

Cet article examine les possibilités d'usage stratégique des libertés de circulation (liberté d'établissement et libre prestation de services) par les entreprises. Les entreprises peuvent faire usage des libertés garanties par le droit de l'Union en vue de contourner une législation nationale et soumettre leur activité à la réglementation plus favorable d'un autre Etat membre. Ces stratégies sont en principe licites et sont même encouragées par le droit de l'Union, en ce que des dispositifs comme les guichets uniques réduisent les coûts de transaction. Dans ce contexte, c'est aux Etats que revient la tâche de poser des limites aux stratégies d'entreprises, sous le contrôle du droit européen. Les espaces stratégiques des entreprises apparaissent finalement modelés par trois forces: ouverture de ces espaces par le droit européen, régulation des stratégies par les droits nationaux et coordination des actions des Etats par la coopération administrative et la surveillance mutuelle. [less ▲]

Implicit 2D Numerical Simulation of Materials Submitetd to High Strain Rates including Fracture

in Key Engineering Materials [=KEM] (2013), 535-536

In this paper, we present a general consistent numerical formulation able to take into account strain rate and thermal effects of the material behavior. A thermomechanical implicit approach for element ... [more ▼]

In this paper, we present a general consistent numerical formulation able to take into account strain rate and thermal effects of the material behavior. A thermomechanical implicit approach for element erosion to model material failure is also presented. The numerical model will be illustrated by applications both from the metal forming and the impact domain. All these physical phenomena have been included in an implicit dynamic oriented object finite element code (implemented at LTAS-MN²L, University of Liège, Belgium) named Metafor [less ▲]

Modeling and Prediction of Time-Varying Environmental Data Using Advanced Bayesian Methods

in Exploring Innovative and Successful Applications of Soft Computing (2013)

The problem of state/parameter estimation represents a key issue in crop models which are nonlinear, non-Gaussian and include a large number of parameters. The prediction errors are often important due to ... [more ▼]

The problem of state/parameter estimation represents a key issue in crop models which are nonlinear, non-Gaussian and include a large number of parameters. The prediction errors are often important due to uncertainties in the equations, the input variables, and the parameters. The measurements needed to run the model (input data), to perform calibration and validation are sometimes not numerous or known with some uncertainty. In these cases, estimating the state variables and/or parameters from easily obtained measurements can be extremely useful. In this work, we address the problem of modeling and prediction of leaf area index and soil moisture (LSM) using state estimation. The performances of various conventional and state-of-the-art state estimation techniques are compared when they are utilized to achieve this objective. These techniques include the extended Kalman filter (EKF), unscented Kalman filter (UKF), particle filter (PF), and the more recently developed technique variational Bayesian filter (VF). The objective of this work is to extend the state and parameter estimation techniques (i.e., EKF, UKF, PF and VF) to better handle nonlinear and non-Gaussian processes without a priori state information, by utilizing a time-varying assumption of statistical parameters. In this case, the state vector to be estimated at any instant is assumed to follow a Gaussian model, where the expectation and the covariance matrix are both random. The randomness of the expectation and the covariance of the state/parameter vector are assumed here to further capture the uncertainty of the state distribution. One practical choice of these distributions can be a Gaussian distribution for the expectation and a multi-dimensional Wishart distribution for the covariance matrix. The assumption of random mean and random covariance of the state leads to a probability distribution covering a wide range of tail behaviors, which allows discrete jumps in the state variables. [less ▲]

Organiser les entités territoriales wallonnes en structures porteuses de projets et de solidarité pour répondre aux besoins (Dynamique "Horizon 2022" : Mobilisation du territoire, les communautés de territoire et leur organisation)

Report (2013)

Le rapport trace les enjeux d'une réorganisation du territoire wallon autour d'une nouvelle structuration infrarégionale de l'espace régional. Il dresse succinctement l'évolution récente des coopérations ... [more ▼]

Le rapport trace les enjeux d'une réorganisation du territoire wallon autour d'une nouvelle structuration infrarégionale de l'espace régional. Il dresse succinctement l'évolution récente des coopérations supracommunales et interrégionales, notamment autour des villes. [less ▲]

CO2, CH4 and N2O dynamics and fluxes in the brackish Lake Grevelingen (The Netherlands)

Poster (2013)

Lake Grevelingen in the South West Netherlands is a former estuary locked off from the sea by two dikes and a brackish lake since 1971 (salinities from 29 to 33 during our sampling). It is connected with ... [more ▼]

Lake Grevelingen in the South West Netherlands is a former estuary locked off from the sea by two dikes and a brackish lake since 1971 (salinities from 29 to 33 during our sampling). It is connected with the North Sea by sluices, has a surface area of 108 km2, a mean depth of 5.3 m, a maximum depth of 48 m, and about 60% of the area the depth is less than 5 m. In summer, anoxia occurs in bottom waters. From January 2012 to December 2012 a biogeochemical survey was conducted at monthly interval at a fixed station (35 m depth) at Den Osse. Here, we focus on the analysis of partial pressure of CO2, and concentrations of CH4 and N2O obtained throughout the water column. pCO2 followed a typical seasonal cycle for temperate coastal environments shifting from CO2 over-saturation in winter to spring CO2 under-saturation due to the spring phytoplankton bloom, and shifting back to over-saturation in fall. Unlike the adjacent Southern Bight of the North Sea and the adjacent Oosterschelde, CO2 under-saturation prevailed in summer in Lake Grevelingen. CH4 values were minimal in winter ( 20 nM) and as stratification developed during spring and summer a distinct maximum of CH4 (up to 730 nM) developed at the pycnocline (5 to 10 m). N2O showed little seasonal variations and only a very faint increase with depth, except in August when bottom waters became anoxic. At this time, N2O shown a maximum ( 22 nM) at the oxycline (probably related to enhanced N2O production by nitrification at low O2 concentrations), and decreased in the anoxic layer ( 3 nM) (probably related to denitrification). [less ▲]

Emergence: une notion polysémique

in Wintgens, Sophie; Grandjean, Geoffrey (Eds.) Acteurs émergents perspectives pour la gouvernance mondiale (2013)

La contribution se penche sur la notion d'émergence et identifie trois interprétation possible: les économico-financières, les politologiques et les sociologiques.

International Public Contracts : Applicable Law and Dispute Resolution

in Audit, Mathias; Schill, Stephan (Eds.) THE INTERNATIONALIZATION OF PUBLIC CONTRACTS (2013)

This paper examines the legal regimes of international contracts concluded by States and public entities. These agreements come in many shape and form. Some of these contracts are long term arrangements ... [more ▼]

This paper examines the legal regimes of international contracts concluded by States and public entities. These agreements come in many shape and form. Some of these contracts are long term arrangements involving massive amount of capital and touching upon key resources of the State. Other contracts are of more limited scope. The paper focuses on the law applicable to such agreements. The importance of determining the law applicable to 'state contracts' follows from the peculiar features of a contractual relation with a State, and most notably the additional risk this creates. As in the domestic context, the State is not a contractual partner like any other. It comes into the contractual relationship with its exorbitant powers and sometimes bad manners. This explains why, in contrast with private agreements, where such clauses are too often neglected, provisions on applicable law and settlement of disputes are often considered the “most sensitive legal issues” in the framework of contracts concluded by States. In this against this background that public international contracts will be examined. The attention will first focus on the determination of the law applicable to such contracts (section 1). Thereafter the focus will be on the various stabilization mechanisms used in practice (section 2). This will include both direct stabilization mechanisms and dispute resolution provisions, as these two elements are central to the legal regime of public international contracts. An attempt will be made to present both the generalprinciples and the current practice of States – even though it is difficult to draw general lessons as contracts concluded by states, which come in various formats and shapes, are not easily accessible. [less ▲]

Etude de modes de production de charbon de bois sur l'axe Lubumbashi-Kasenga

Poster (2013)