Non-monotoniticies and the all-pay auction tie-breaking rule

Discontinuous games, such as auctions, may require special tie-breaking rules to guarantee equilibrium existence. The best results available ensure equilibrium existence only in mixed strategy with endogenously defined tie-breaking rules and communication of private information. We show that an all-pay auction tie-breaking rule is sufficient for the existence of pure strategy equilibrium in a class of auctions. The rule is explicitly defined and does not require communication of private information. We also characterize when special tie-breaking rules are really needed

New family of potentials with analytical twiston-like solutions

In this letter we present a new approach to find analytical twiston models. The effective two-field model was constructed by a non-trivial combination of two one field systems. In such an approach we successfully build analytical models which are satisfied by a combination of two defect-like solutions, where one is responsible to twist the molecular chain by $180^{\,0}$, while the other implies in a longitudinal movement. Such a longitudinal movement can be fitted to have the size of the distance between adjacent molecular groups. The procedure works nicely and can be used to describe the dynamics of several other molecular chains.Comment: 7 pages, 3 figure

Interaction between water soluble and volatile compounds of Cistus ladanifer L.

Phytotoxic activity of single and combined application of water soluble and volatile compounds of Cistus ladanifer on germination and early root growth of subterranean clover. Was investigated. Total germination, lag and speed of germination were both inhibited and stimulated, with the activity of volatiles on total germination depending upon the presence of water solubles. Antagonism between water solubles and volatiles was always found, resulting in a reduction of inhibition or a shift from inhibition to stimulation. It is suggested that the simultaneous presence of water solubles and volatiles might result in changes of the chemical nature of metabolites released by C. ladanifer. Early root growth was always inhibited but only by water solubles, and no interaction was found. The ecological implications of these results are discussed in terms of the exhaustion of competitors seedbanks by a two-step process in which germination is less inhibited or even stimulated by water solubles and volatiles, followed by a stronger and volatiles-independent inhibition of early root growth

Ilha de santiago (Cabo Verde) - Notas Florísticas e Fitogeográficas

Dez taya (Achyranthes aspera var.pubescens, Andropogon/astigiatus, Anthephora cristata, Cenchrus bgorus, Chamaecrista mimosoides, Commelina d~@sa subsp. d$iia, Forsskaolea viridis, Tephrosia linearis, Tolpis/arinulosa e Stylosanthes humilis) sãom encionadopse lap rimeirav ez paraS antiagoE. stacitacáo constitui também,p ara4 deles,a suap rimeirar eferencia para o arquipélagod e CaboV erde. A ~orrkcia de espéciese ndémicasc,u ja presentan estai lha não era verificada desdeh á longa data, é ylientada. Pelo valor dasc omunidadevse getaisq uen eleso correm, sãor eferidosa lgunslo caisp articti+nente importantes.biJorus, Chamaecrista mimosoides, Commelina dl@ia subsp. d@úsa, Forsskaolea viridis, Tephrosia finearis, To~pisfürinulosa and Stylosanthes humilis) are quoted for the first time to Santiago, being ‘four of them unknown in the Cape Verde archipelago. It is remarked the observation of endemic species which :presente, although known in this island, where not seen for a long time. In reasori of its interesting plant communities,it is referred somei mportants ites