An approach to the synthesis of qualitative ecological information from aquatic coleoptera communities

A list of 196 Coleoptera taxa, larvae and adults, covering 113 species, was obtained from several surveys of a flood plain of the Rhô river. From published reports and personal experience, each taxon is linked with the modalities of nine environmental and three biological variables. The resulting 12 ecological profiles for 196 taxa are analysed by correspondence analysis. The simultaneous ordination of the taxa and variables allows presentation of the more synthetic correspondence between the Coleoptera and their ecological and biological characteristics. The niche dimensions of the 12 variables tested here are organized along a current-substrate gradient, from stones in rapid flow to mud in still water, which is associated with the other ecological conditions. This ordination reflects environmental conditions in a transverse direction, particularly from the central channel to the furthest annexes of the river. The Coleoptera are shown to be describers of the connectivity with the main channel. The 196 studied taxa are positioned along the gradient. They are subdivided into seven faunal groups based on their habitat range or niche width. The larger species are confined to the stagnant side of the gradient. Other variables, such as feeding and vertical distribution, clearly separate carnivores from herbivores and also larvae from adults. The next step of this study will be to extend these investigations to other functional variables and to all the species of Coleoptera in France. The information given by the Coleoptera will then be compared with actual field measurements.     

Benign glandular inclusions in inguinal and abdominopelvic lymph nodes in gynecologic pathology

From 4 cases recently seen at the Institut Gustave-Roussy, this report describes the pathological and evolutive features of benign glandular inclusions in inguinal, pelvic or abdominal lymph nodes. These lesions are defined by the presence of tubular formations in lymph nodes, lined by a single layer of epithelium which is cuboidal or columnar and resembled that of tubal epithelium with ciliated, secretory and intercalary cells. In most cases, benign glandular inclusions in lymph nodes still quiescent. In rare instances, they may proliferate and become papillary. The association of proliferating glandular inclusions in lymph nodes with borderline tumor of the ovary raises the problem of their primary or metastatic origin. However, their pathological features argues for a primary origin in lymph nodes. Thus, we think that a metastatic potential of borderline tumors of the ovary is not supported by any convincing argument.     

Effects of ketotifen on human lymphocytes in vitro and in vivo

The effects of the antiasthmatic drug ketotifen (CAS 34580-13-7) on human mononuclear leukocytes were studied in vitro and in vivo. In vitro ketotifen concentration-dependently inhibited mitogen-stimulated lymphocyte proliferation. High ketotifen concentrations also inhibited T-lymphocyte mitogen- and adenosine triphosphate stimulated increases in intracellular Ca2+ in lymphocytes and the U937 human monocyte precursor cell line, respectively; this involved inhibition of both Ca2+ influx and intracellular mobilization. In in vivo experiments, treatment of healthy volunteers with 1 mg ketotifen b.i.d. for 7 d did not alter the number or subset composition of circulating lymphocytes. Moreover, the mitogen-stimulated in vitro proliferation of lymphocytes obtained before and after ketotifen treatment in vivo was similar. It is concluded that high ketotifen concentrations can inhibit the activation of resting lymphocytes in vitro but standard ketotifen treatment does not notably affect the number of function of circulating lymphocytes in vivo.     

Aide in decision-making: contribution to uncertainties in three-dimensional measurement

The authorities of the standards organization International Organization of Standardization (ISO) advocate mastering any uncertainties in all parts of the industrialization process. In the three-dimensional (3D) measurement process, uncertainty is usually obtained at the end of a battery of tests. It is defined as a whole because it includes several types of errors, known systematic components, unknown systematic components and random components. Automated calculations of uncertainty can be made based on statistics. This method is based on statistical concepts, which are in accordance with “The Guide to the expression of the uncertainty in measurement” (GUM). It also enables us to generate uncertainties on the verification of ISO specifications (or specs in the ISO directives). In the course of this article, a usage will be presented that takes the knowledge of uncertainties into account: this usage will help the operator to take a decision on the conformance of a mechanical part in reference to its conformance to geometric tolerance.     

Differences of behaviour in electrooxidation of 3,3′-dimethoxybenzidine and its N,N,N′,N′-tetraalkylated derivatives: a further example of potential inversion

The anodic oxidation of 3,3′-dimethoxybenzidine and its derivatives were studied by cyclic voltammetry, voltammetry at a rotating platinum electrode, chronopotentiometry and constant potential coulometry. The exhaustive oxidation of 3,3′-dimethoxybenzidine led at the potential of the first oxidation peak and second oxidation peak, respectively, to a stable cation radical salt (characterized by ESR spectroscopy) and to a quinone-diimine. Whereas, 3,3′-dimethoxy-N,N,N′,N′-tetramethylbenzidine afforded directly a dication salt owing to potential inversion 3,3′-dimethoxy-N,N,N′,N′-tetraethylbenzidine gave the corresponding soluble cation radical salt.     

Potential science-technology spillovers in regions: An insight on geographic co-location of knowledge activities in the EU

This article depicts some features of the geography of science and technology outputs in the EU, with a particular attention to regional “co-location” of these two pillars of the “knowledge-based society”. Economists have, for a decade, paid great attention to local “spillovers” stating that industrial firms often draw advantages from the presence of nearby academic centres. The presence in the same areas of strong academic and technological resources is both a condition and a result of science-technology interactions. Concentrating on publications and patents as proxies of the science and technology level in regions, we built a typology of regions according to their commitment to the two knowledge-base activities and then analysed the co-locations of science and technology from several points of view. A fine-grain lattice, mainly based on standard Nuts3 level, was used. Co-location, at the EU level, is not a general rule. A strong potential for spillover/ interaction does exist in the top-class regions which concentrate a high proportion of European S and T output. But for regions with a small/medium level of S&T activity, a divergence of orientations appears between a science-oriented family and a technology-oriented family, indicating an imbalance between local S and T resources. If we look at the S-oriented regions, whilst controlling for underlying factors, such as population and regional economic product, a significant geographic linkage between T and S appears. This suggests a trajectory of science-based technological development. A careful examination of S&T thematic alignments and specialisation is necessary to develop the hypothesis that fostering academic resources could increase the technological power along a growth path. This revised version was published online in August 2006 with corrections to the Cover Date.     

MODELISATION PRINCIPLES FOR DRYING OF GELS

When one wants to understand and model the drying of high water content gels, one needs to gather all thermal physical parameters and to derive a physical model based on independently measured parameters. We chose to work experimentally and theoretically on water diffusion and drying of spheres of polyacrylamide gel.

We have demonstrated the strong influence of vitreous transition on the relationship of water diffusivity with moisture content. Values of the diffusion coefficient and temperature shift factor for diffusion have been proposed.

Convective and micro-wave drying kinetics show the presence of a drying phase purely specific to radiation absorption. Finally, we have proposed a mathematical model containing independent physical parameters, which' not only predicts mass fluxes but also analyses critical physical phenomena.     

Automatic partitioning of unstructured meshes for the parallel solution of problems in computational mechanics

Most of the recently proposed computational methods for solving partial differential equations on multiprocessor architectures stem from the 'divide and conquer' paradigm and involve some form of domain decomposition. For those methods which also require grids of points or patches of elements, it is often necessary to explicitly partition the underlying mesh, especially when working with local memory parallel processors. In this paper, a family of cost-effective algorithms for the automatic partitioning of arbitrary two- and three-dimensional finite element and finite difference meshes is presented and discussed in view of a domain decomposed solution procedure and parallel processing. The influence of the algorithmic aspects of a solution method (implicit/explicit computations), and the architectural specifics of a multiprocessor (SIMD/MIMD, startup/transmission time), on the design of a mesh partitioning algorithm are discussed. The impact of the partitioning strategy on load balancing, operation count, operator conditioning, rate of convergence and processor mapping is also addressed. Finally, the proposed mesh decomposition algorithms are demonstrated with realistic examples of finite element, finite volume, and finite difference meshes associated with the parallel solution of solid and fluid mechanics problems on the iPSC/2 and iPSC/860 multiprocessors.     

IDENTIFICATION OF NITROGEN COMPOUNDS AND THEIR EVOLUTIONDURINGAGEING NABSENCE ANDPRESENCE OF ADDITIVES EFFICIENCYOFHYDROTREATMENT

As established by several previous works, nitrogen compounds play a prominent role in the evolution of middle distillates containing cracked components, particularly regarding sediment formation and color evolution.

In a first part, this paper describes and compares stability properties of fuel blends using both an accelerated ageing method at 120°C (248°F ) and long term storage methods at 43°C(110°F) -ASTM 0 4625 - and at ambient temperature. Effectiveness of stabilizing additives is also evaluated. In mixtures containing LCOs, insoluble products are formed progressively during ageings, more or less rapidly according to the chemical constitution of the mixtures.

Then, it reports the complete identification of nitrogen compounds using gas chromatography equipped with a selective nitrogen detector and mass spectrometry showing that in light cycle oils, alkyl indoles and carbazoles are the main families.

Evolution of these compounds was followed kinetically during ageings in absence and presence of additives and alkyl indoles appeared as the moat evolutionary.

It appeared that some additives avoided evolutions of alkyl indoles without preventing sediment formation and color evolution. Oxidation mechanism involving nitrogen compounds should not be the only one to explain the storage evolutions of middle distillates.

Hydrotreatment converts all the alkyl indoles of LCO and prevents coloration end deposits in the storage of the mixtures of steaight-run distillates and LCOs.     

Prebiotic synthesis of sequential peptides on the Hadean beach by a molecular engine working with nitrogen oxides as energy sources

Addressing the still open question of the prebiotic origin of sequential macromolecules (peptides, nucleic acids) on the primitive Earth, we describe a molecular engine (the primary pump), which works at ambient temperature and continuously generates, elongates and complexifies sequential peptides. This new scenario is based on a cyclic reaction sequence, whose keystep is the activation of amino acids into their N‐carboxyanhydrides (NCA) through nitrosation by NOx. This process could have taken place on tidal beaches; it requires a buffered ocean, emerged land and a nitrosating atmosphere. With the help of geochemical studies and computer simulations of atmosphere photochemistry, we show that the primitive Earth during the Hadean may have satisfied all these requirements. © 2001 Society of Chemical Industry.