Search results for "Ligo"

Defining the course of tumefactive multiple sclerosis: A large retrospective multicentre study

2021

Background and purpose: Tumefactive multiple sclerosis (TuMS) (i.e., MS onset presenting with tumefactive demyelinating lesions [TDLs]) is a diagnostic and therapeutic challenge. We performed a multicentre retrospective study to describe the clinical characteristics and the prognostic factors of TuMS. Methods: One hundred two TuMS patients were included in this retrospective study. Demographic, clinical, magnetic resonance imaging (MRI), laboratory data and treatment choices were collected. Results: TuMS was found to affect women more than men (female:male: 2.4), with a young adulthood onset (median age: 29.5 years, range: 11–68 years, interquartile range [IQR]: 38 years). At onset, 52% of …

Exploring the Specificity of Rationally Designed Peptides Reconstituted from the Cell-Free Extract of Deinococcus radiodurans toward Mn(II) and Cu(II)

2020

A series of five rationally designed decapeptides [DEHGTAVMLK (DP1), THMVLAKGED (DP2), GTAVMLKDEH (Term-DEH), TMVLDEHAKG (Mid-DEH), and DEHGGGGDEH (Bis-DEH)] have been studied for their interactions with Cu(II) and Mn(II) ions. The peptides, constructed including the most prevalent amino acid content found in the cell-free extract of Deinococcus radiodurans (DR), play a fundamental role in the antioxidant mechanism related to its exceptional radioresistance. Mn(II) ions, in complex with these peptides, are found to be an essential ingredient for the DR protection kit. In this work, a detailed characterization of Cu(II) systems was included, because Cu(II)–peptide complexes have also shown r…

Growth and sustainability of agricultural systems: the case of Sicilian wine-growing farms

2016

International audience; The Sicilian wine-growing sector is characterised by the presence on the one hand of many small enterprises that limit their activity to the first stage of the supply chain (field production) and on the other of few enterprises that adopt a strategy of total vertical integration, from the production to the sale of wine. The first group of enterprises operates in a competitive market and in many cases with marginal revenues that are lower than marginal costs, leading entrepreneurs to abandon the activity of grape production. The second group operates in an oligopolistic market and it is able to compete in an international market. Findings reveal that competitive advan…

Les followers ont-ils vraiment de l'importance dans le modèle de Stackelberg?

2011

In this paper, we consider a T-stage linear model of Stackelberg oligopoly. First, we show geometrically and analytically that under the two conditions of linear market demand and identical constant marginal costs, the T-stage Stackelberg model reduces to a model where T oligopolies exploit residual demand sequentially. At any stage, leaders behave as if followers did not matter. Second, we study social welfare and convergence toward competitive equilibrium. Especially, we consider the velocity of convergence as the number of firms increases. The convergence is faster when reallocating firms from the most to the less populated cohort until equalizing the size of all cohorts.

The beer market and advertising expenditure

2009

PurposeThe purpose of this paper is to examine the impacts of advertising expenditure on brands' market shares, utilizing a novel four‐week advertising‐sales data from the highly competitive oligopolistic Finnish beer market in which price competition among the homogeneous larger‐type beer brands is not allowed during the period of the study.Design/methodology/approachCompetition is modelled using the Lanchester model. The impacts of advertising on market shares are estimated using the impulse‐response functions from vector autoregression, and the full information maximum likelihood and advertising elasticities.FindingsSome new insights into beer market dynamics are obtained. First, the imp…

Design and physicochemical characterization of poly(amidoamine) nanoparticles and the toxicological evaluation in human endothelial cells: applicatio…

2013

In this study, we investigated nanoparticles formulated by self-assembly of a biodegradable poly(amidoamine) (PAA) and a fluorescently labeled peptide, in their capacity to internalize in endothelial cells and deliver the peptide, with possible applications for brain drug delivery. The nanoparticles were characterized in terms of size, surface charge, and loading efficiency, and were applied on human cerebral microvascular endothelial cells (hCMEC/D3) and human umbilical vein endothelial cells (Huvec) cells. Cell-internalization and cytotoxicity experiments showed that the PAA-based nanocomplexes were essentially nontoxic, and the peptide was successfully internalized into cells. The result…

Controlled delivery using oligonucleotide-capped mesoporous silica nanoparticles.

2010

Proteins in amorphous saccharide matrices: Structural and dynamical insights on bioprotection

2013

Bioprotection by sugars, and in particular trehalose peculiarity, is a relevant topic due to the implications in several fields. The underlying mechanisms are not yet clearly elucidated, and remain the focus of current investigations. Here we revisit data obtained at our lab on binary sugar/water and ternary protein/sugar/water systems, in wide ranges of water content and temperature, in the light of the current literature. The data here discussed come from complementary techniques (Infrared Spectroscopy, Molecular Dynamics simulations, Small Angle X-ray Scattering and Calorimetry), which provided a consistent description of the bioprotection by sugars from the atomistic to the macroscopic …

The effect of polycations on early cement paste

2010

International audience; This paper studies the possibility for improving the ductility of cement based materials by means of oligocationic additives. Actually, the setting of cement is due to ionic correlation forces between highly negatively charged C-S-H nanoparticles throughout a calcium rich solution. The main drawback of this strong attraction is its very short range that results in low elastic deformation of hydrated cementitious materials. A way to enlarge the attraction range between C-S-H particles would be to add cationic oligomers that would compete with calcium ions modifying the ionic correlation forces via a bridging mechanism of longer range, which could lead to a more ductil…

Polymerizable Well-Defined Oligo(thiophene amide)s and their ROMP Block Copolymers

2009

We report the synthesis of conjugated thiophene amide oligomers that constitute a new class of chromophores with potential for optoelectronic applications. The synthesis of defined norbornene-substituted oligothiophene amides using conventional coupling chemistry is described. Their electronic properties depend on the degree of oligomerization as UV/Vis and fluorescence spectroscopy demonstrate. A significant red shift in the spectra upon an increase in the oligomer length evidences conjugation of the thiophene rings via the amide linkages. ROMP of the norbornene-substituted oligomers gives homopolymers and block-copolymers with a solubilizing second block. The amphiphilic character of the …