3,876 research outputs found
Strategic Behaviour, Resource Valuation and Competition in Electricity Markets
By means of a suitable Bayesian game we study spot electricity markets from a structural point of view. We address the problem of individual and aggregate eficciency and we show how to value water from market observables. We compare the former to engineering methods and apply our methodology to Colombian spot electricity market. Our results show that big gas and small hydro plants overbid, resources are undervalued by engineering costs and aggregate costs would have been considerably smaller if agents had played optimally. Revealed costs show a substantial gain in eficciency in the Vickrey auction compared to the actual uniform auction.Multi-unit auctions, Oligopoly, electricity markets
Cluster size entropy in the Axelrod model of social influence: small-world networks and mass media
We study the Axelrod's cultural adaptation model using the concept of cluster
size entropy, that gives information on the variability of the cultural
cluster size present in the system. Using networks of different topologies,
from regular to random, we find that the critical point of the well-known
nonequilibrium monocultural-multicultural (order-disorder) transition of the
Axelrod model is unambiguously given by the maximum of the
distributions. The width of the cluster entropy distributions can be used to
qualitatively determine whether the transition is first- or second-order. By
scaling the cluster entropy distributions we were able to obtain a relationship
between the critical cultural trait and the number of cultural
features in regular networks. We also analyze the effect of the mass media
(external field) on social systems within the Axelrod model in a square
network. We find a new partially ordered phase whose largest cultural cluster
is not aligned with the external field, in contrast with a recent suggestion
that this type of phase cannot be formed in regular networks. We draw a new
phase diagram for the Axelrod model in regular networks.Comment: 21 pages, 7 figure
Vaccination of Cattle with the N Terminus of LppQ of Mycoplasma mycoides subsp. mycoides Results in Type III Immune Complex Disease upon Experimental Infection
Contagious bovine pleuropneumonia (CBPP) is a serious respiratory disease of cattle caused by Mycoplasma mycoides subsp. mycoides. Current vaccines against CBPP induce short-lived immunity and can cause severe postvaccine reactions. Previous studies have identified the N terminus of the transmembrane lipoprotein Q (LppQ-N') of M. mycoides subsp. mycoides as the major antigen and a possible virulence factor. We therefore immunized cattle with purified recombinant LppQ-N' formulated in Freund's adjuvant and challenged them with M. mycoides subsp. mycoides. Vaccinated animals showed a strong seroconversion to LppQ, but they exhibited significantly enhanced postchallenge glomerulonephritis compared to the placebo group (P = 0.021). Glomerulonephritis was characterized by features that suggested the development of antigen-antibody immune complexes. Clinical signs and gross pathological scores did not significantly differ between vaccinated and placebo groups. These findings reveal for the first time the pathogenesis of enhanced disease as a result of antibodies against LppQ during challenge and also argue against inclusion of LppQ-N' in a future subunit vaccine for CBPP
Unusual magneto-transport of YBa2Cu3O7-d films due to the interplay of anisotropy, random disorder and nanoscale periodic pinning
We study the general problem of a manifold of interacting elastic lines whose
spatial correlations are strongly affected by the competition between random
and ordered pinning. This is done through magneto-transport experiments with
YBa2Cu3O7-d thin films that contain a periodic vortex pinning array created via
masked ion irradiation, in addition to the native random pinning. The strong
field-matching effects we observe suggest the prevalence of periodic pinning,
and indicate that at the matching field each vortex line is bound to an
artificial pinning site. However, the vortex-glass transition dimensionality,
quasi-2D instead of the usual 3D, evidences reduced vortex-glass correlations
along the vortex line. This is also supported by an unusual angular dependence
of the magneto-resistance, which greatly differs from that of Bose-glass
systems. A quantitative analysis of the angular magnetoresistance allows us to
link this behaviour to the enhancement of the system anisotropy, a collateral
effect of the ion irradiation
- …