Search results for "ROLE"

The pyrrole moiety as a template for COX-1/COX-2 inhibitors

2000

Aroyl- and thiophene-substituted pyrrole derivatives have been synthesized as a new class of COX-1/COX-2 inhibitors. The inhibition of COX-1 was evaluated in a biological system using bovine PMNLs as the enzyme source, whereas LPS-stimulated human monocytes served as the enzyme source for inducible COX-2. The determination of the concentration of arachidonic acid metabolites was performed by HPLC for COX-1 and RIA for COX-2. Variation of the substitution pattern led to a series of active compounds which showed inhibition for COX-1 and COX-2. Structural requirements for the development of COX-1/COX-2 inhibitors are discussed.

Frente a la Dictadura

Retrat de l'autor en coberta

Development of a new peat-based oil sorbent using peat pyrolysis

2013

The growing use and transport of crude oil and oil products has led to increasing numbers of oil spillages of various scales. Oil sorbents have been extensively used for remediation of the consequences of such accidents. The aim of this study is to investigate the possible use of peat and its thermal treatment products for oil sorption. Peat as an oil sorbent has poor buoyancy characteristics, relatively low oil sorption capacity and low hydrophobicity. However, thermal treatment (low-temperature pyrolysis and synthesis of peat-based activated coal) helps to significantly improve its sorptive characteristics. Peat is a potential material for oil sorption because it has such advantages as lo…

White-light-modified Talbot array illuminator with a variable density of light spots.

2008

A flexible array illuminator, comprising only two conventional optical elements, with a variable density of bright white-light spots is presented. The key to our method is to obtain with a single diffractive lens an achromatic version of different fractional Talbot images, produced by free-space propagation, of the amplitude distribution at the back focal plane of a periodic refractive microlens array under a broadband point-source illumination. Some experimental results of our optical procedure are also shown.

Fabrication of Diffractive Optics: Surface Reliefs and Artificial Dielectrics

1997

After a period of fundamental theoretical research, the field of diffractive optics is now reaching a time of assessment, when we can define the useful limits of each design procedure. Selecting a suitable procedure derives from a compromise between several factors, including design time, desired optical efficiency, and precision. A major consideration in finding such a compromise has been, and still is today, the availability of technologies which can realize the design by generating the diffracting structure with assigned tolerances.

Deep fluid transfer evidenced by surface deformation during the 2014–2015 unrest at Piton de la Fournaise volcano

2016

International audience; Identifying the onset of volcano unrest and providing an unequivocal identification of volcano reawakening remain challenging problems in volcanology. At Piton de la Fournaise, renewal of eruptive activity in 2014–2015, after 41 months of quiescence and deflation, was associated with long-term continuous edifice inflation measured by GNSS. Inflation started on June 9, 2014, and its rate progressively increased through 2015. Inflation onset was rapidly followed by an eruption on June 20–21, 2014, showing that volcano reactivation can be extremely fast, even after long non-eruptive phases. This short-lived eruption involved a shallow source (1.3–1.9 km depth below the …

Geochemical investigations applied to active fault detection in a volcanic area: the North-East Rift on Mt. Etna (Sicily, Italy)

1999

Geochemical investigations were performed on the Northeast Rift of Mt. Etna, a prominent volcanic structure of this volcano. Low-temperature fumaroles were found on the upper part of this area and the isotopic compositions of C(CO2) and He suggest a likely magmatic origin of the emitted gases. On the contrary, very low degassing was found in the lower part of the NE-Rift, with CO2 concentrations generally very close to those in air. This pattern is probably due to sealing of the eruptive fissures by the repeated injections of magma solidified into dikes and by consequent shallow hydrothermal alteration of the fissured rocks due to residual magma degassing. High soil CO2 concentrations were …

Parental beliefs and their role in child-rearing

2001

Beliefs have been a topic of considerable interest among researchers in various fields. In this article 71 articles reporting a study on parental beliefs and published in the course of fifteen years (1980–1995) are reviewed. After clarifying the term ‘belief’, the topics and the methodological solutions of the studies are discussed. Throughout the discussion the question of the origins of parental beliefs and the belief — behaviour dilemma are dealt with. Finally, the implications of the findings and suggestions for future research are presented.

Toward an Understanding of the Molecular Mechanism of the Reaction between 1-Methylpyrrole and Dimethyl Acetylenedicarboxylate. An ab Initio Study

1998

The molecular mechanism for the reaction between 1-methylpyrrole and dimethyl acetylenedicarboxylate (DMAD) has been studied using ab initio methods. Two alternative reaction pathways have been considered, both of which correspond to stepwise processes with initial, rate-determining formation of a common zwitterionic intermediate. This intermediate is formed by nucleophilic attack of the pyrrole ring to the carbon−carbon triple bond of DMAD. Closure of this intermediate (pathway A) affords a [4 + 2] cycloadduct, whereas intramolecular proton transfer (pathway B) affords a Michael adduct. The much larger potential energy barrier of the second step in pathway B relative to pathway A is respon…

The Graduates in the Knowledge and Innovation Society

2011

According to the crucial importance of innovation for modern economies, the role of graduates regarding innovation appears to be a major topic when their performances in the labour market at stake. Five main questions are addressed in this chapter: (1) What does innovation mean? (2) Which organisations are likely to be more innovative? (3) What role do Higher Education graduates play regarding innovation? (4) Are they equipped to do develop innovation? (5) Which are the occupations more related to innovation, and are innovative activities rewarded? The results presented in this chapter confirm that higher education graduates are crucial actors in the innovation process. The jobs of innovati…