Off-shell BRST-VSUSY superalgebra for D=4 BF theories in the superconnection formalism

We propose the superconnection formalism to construct the off-shell BRST-VSUSY superalgebra for D=4 BF theories. The method is based on the natural introduction of physical fields as well as auxiliary fields via superconnections and their associated supercurvatures defined on a superspace. We also give a prescription to build the off-shell BRST-VSUSY exact quantum action.Comment: Latex, 13 pages, no figures, comments and references adde

On Auxiliary Fields in BF Theories

We discuss the structure of auxiliary fields for non-Abelian BF theories in arbitrary dimensions. By modifying the classical BRST operator, we build the on-shell invariant complete quantum action. Therefore, we introduce the auxiliary fields which close the BRST algebra and lead to the invariant extension of the classical action.Comment: 7 pages, minor changes, typos in equations corrected and acknowledgements adde

Monte Carlo simulation of a hard-sphere gas in the planar Fourier flow with a gravity field

By means of the Direct Simulation Monte Carlo method, the Boltzmann equation is numerically solved for a gas of hard spheres enclosed between two parallel plates kept at different temperatures and subject to the action of a gravity field normal to the plates. The profiles of pressure, density, temperature and heat flux are seen to be quite sensitive to the value of the gravity acceleration $g$. If the gravity field and the heat flux are parallel ($g>0$), the magnitudes of both the temperature gradient and the heat flux are smaller than in the opposite case ($g<0$). When considering the actual heat flux relative to the value predicted by the Fourier law, it is seen that, if $g>0$, the ratio increases as the reduced local field strength increases, while the opposite happens if $g<0$. The simulation results are compared with theoretical predictions for Maxwell moleculesComment: 18 pages (LaTex), 7 figures (eps

Habitat Variation in Vernal Pool Ecosystems on Both Sides of the Strait of Gibraltar

We studied vernal pool (VP) ecosystems along a latitudinal gradient crossing the Strait of Gibraltar in order to determine its role in the distribution of VP plant communities. We analyzed flora, vegetation, physical–chemical water parameters, and climatic data from two vernal pool areas on both the European (Iberian) and African (Moroccan) sides of the Strait. Despite the minor distance between both territories, the pools clearly differed in species composition and ecology. However, they showed a similar vegetation zonation in growth forms, including isoetid, batrachiid, and helophytic vegetation. The distribution of the plant communities was related to nutrient load, temperature, and precipitation. Water nitrate concentration was higher in Morocco, where VPs are characterized by Isoetes velata subsp. adspersa and Ranunculus saniculifolius communities. Iberian VPs had lower water nitrate content, and were characterized by Isoetes velata subsp. velata and Ranunculus peltatus communities. We think this nutrient difference is likely to be caused by the different land management regime on each side of the Strait, with more intensive agriculture in Morocco. Long-term (historical) and present-day (ecological) processes have been proposed to account for the habitat variation in vernal pool ecosystems on both sides of the Strait of Gibraltar

Nombre chromosomique de quelques Angiospermes marocaines

Se indican los números cromosómicos de cinco taxones pertenecientes a cinco familias de Angiospermas de Marruecos: Allium porrum 2n=32; Armeria simplex 2n=18; Asphodelus ramosus subsp. ramosus n=28; Delphinium nanum subsp. nanum 2n=16 et Dipcadi serotinum 2n=8 et 32. Cada taxon se acompaña de una fotografía en mitosis o meiósis así como de un breve comentario."Chromosome numbers of some Moroccan angiosperm". Chromosome numbers of five taxa from five families of Moroccan angiosperms are reported: Allium porrum 2n=32; Armeria simplex 2n=18; Asphodelus ramosus subsp. ramosus n=28; Delphinium nanum subsp. nanum 2n=16 and Dipcadi serotinum 2n=8 and 32. Mitotic or meiotic metaphases microphotographs and brief comments are detailed for each taxa studied

Nombre chromosomique de quelques plantes a fleurs du Maroc

Se indican los números cromosómicos de once taxones pertenecientes a nueve familias de Angiospermas de Marruecos: Armeria simplex n = 9; Atriplex semibaccata 2n = 18; Cistanche phelypaea n = 20; Echium velutinum subsp. velutinum 2n = 16; Linaria bipartita n = 6; Lupinus cosentinii n = 16; Mesembryanthemum nodiflorum 2n = 38; Plantago amplexicaulis 2n = 10; Sonchus bourgeaui 2n = 16; Vicia lutea et Vicia pseudocracca n = 7. Nueve de estos números se indican por primera vez en poblaciones de Marruecos. Cada taxon estudiado se acompaña de un breve comentario y de la mayoría de ellos se aportan observaciones en mitosis o meiosis.Chromosome numbers of some flowering plants from Morocco. Chromosome numbers of eleven taxa from nine families of Moroccan angiosperms are reported: Armeria simplex n = 9; Atriplex semibaccata 2n = 18; Cistanche phelypaea n = 20; Echium velutinum subsp. velutinum 2n = 16; Linaria bipartita n = 6; Lupinus cosentinii n = 16; Mesembryanthemum nodiflorum 2n = 38; Plantago amplexicaulis 2n = 10; Sonchus bourgeaui 2n = 16; Vicia lutea and Vicia pseudocracca n = 7. Nine of those numbers were reported for the first time in Moroccan populations. Mitotic or meiotic metaphases microphotographs and brief comments are detailed for each taxa studied.Ministère de l’Enseignement Supérieur SVT 04 / 0