Interaction of Gα₁₂ with Gα₁₃ and Gα_q signaling pathways

The G(12) subfamily of heterotrimeric G-proteins consists of two members, G(12) and G(13). Gene-targeting studies have revealed a role for G(13) in blood vessel development. Mice lacking the a subunit of G(13) die around embryonic day 10 as the result of an angiogenic defect. On the other hand, the physiological role of G(12) is still unclear. To address this issue, we generated Galpha(12)-deficient mice. In contrast to the Galpha(13)-deficient mice, Galpha(12)-deficient mice are viable, fertile, and do not show apparent abnormalities. However, Galpha(12) does not seem to be entirely redundant, because in the offspring generated from Galpha(12)+/-Galpha(13) intercrosses, at least one intact Galpha(12) allele is required for the survival of animals with only one Galpha(13) allele. In addition, Galpha(12) and Galpha(13) showed a difference in mediating cell migratory response to lysophosphatidic acid in embryonic fibroblast cells. Furthermore, mice lacking both Galpha(12) and Galpha(q) die in utero at about embryonic day 13. These data indicate that the Galpha(12)-mediated signaling pathway functionally interacts not only with the Galpha(13)- but also with the Galpha(q/11)-mediated signaling systems

Pseudograph associahedra

Given a simple graph G, the graph associahedron KG is a simple polytope whose face poset is based on the connected subgraphs of G. This paper defines and constructs graph associahedra in a general context, for pseudographs with loops and multiple edges, which are also allowed to be disconnected. We then consider deformations of pseudograph associahedra as their underlying graphs are altered by edge contractions and edge deletions.Comment: 25 pages, 22 figure

Unlocking the Potential of Flexible Energy Resources to Help Balance the Power Grid

Flexible energy resources can help balance the power grid by providing different types of ancillary services. However, the balancing potential of most types of resources is restricted by physical constraints such as the size of their energy buffer, limits on power-ramp rates, or control delays. Using the example of Secondary Frequency Regulation, this paper shows how the flexibility of various resources can be exploited more efficiently by considering multiple resources with complementary physical properties and controlling them in a coordinated way. To this end, optimal adjustable control policies are computed based on robust optimization. Our problem formulation takes into account power ramp-rate constraints explicitly, and accurately models the different timescales and lead times of the energy and reserve markets. Simulations demonstrate that aggregations of select resources can offer significantly more regulation capacity than the resources could provide individually.Comment: arXiv admin note: text overlap with arXiv:1804.0389

Making Sense of Non-Binding Retail-Price Recommendations

This paper provides a theoretical rationale for non-binding retail price recommendations (RPRs) in vertical supply relations. Analyzing a bilateral manufacturer-retailer relationship with repeated trade, we show that linear relational contracts can implement the surplusmaximizing outcome. If the manufacturer has private information about production costs or consumer demand, RPRs may serve as a communication device from manufacturer to retailer. We characterize the properties of efficient bilateral relational contracts with RPRs and discuss extensions to settings where consumer demand is affected by RPRs, and where there are multiple retailers or competing supply chains.vertical relationships, relational contracts, asymmetric information, price recommendations

Two Heads Are Less Bubbly than One: Team Decision-Making in an Experimental Asset Market

We study the effect of team decision-making on bubbles and crashes in experimental asset markets of the kind introduced by Smith, Suchanek and Williams (1988). We find that populating such markets with teams of size two instead of individuals significantly reduces the severity of mispricing. In particular we observe that under our teams treatment, deviations in prices away from intrinsic value are significantly smaller in magnitude, shorter in duration and associated with lower volume and price volatility. We also find an unexpected gender effect in team composition, manifesting itself in more extreme – though not consistently more profitable – behaviour by all-male teams. Since these effects are not observed among male participants generally, we conjecture that they may be due to factors specific to the psychology of decision-making in male-dominated environments.asset market experiments, price bubbles, group decision-making, gender composition of teams