Identification and Characterization of the Corazonin Receptor and Possible Physiological Roles of the Corazonin-Signaling Pathway in Rhodnius prolixus.

Neuropeptides control many physiological and endocrinological processes in animals, acting as neuroactive chemicals within the central and peripheral nervous systems. Corazonin (CRZ) is one such neuropeptide that has a variety of physiological roles associated with control of heartbeat, ecdysis behavior initiation, and cuticle coloration. These physiological effects are mediated by the CRZ receptor (CRZR). In order to understand the role of the CRZ-signaling pathway in Rhodnius prolixus, the cDNA sequence encoding the Rhopr-CRZR was isolated and cloned revealing two splice variants (Rhopr-CRZR-α and β). Sequence analysis revealed characteristics of rhodopsin-like GPCRs. Rhopr-CRZR-α and β were dose-dependently activated by Rhopr-CRZ with EC50 values of 2.7 and 1 nM, respectively, when tested in a functional receptor assay using CHOKI-aeq cells. Neither receptors were activated by the evolutionarily-related peptides, Rhopr-AKH, or Rhopr-ACP. For 5th instars, qPCR revealed expression of Rhopr-CRZR transcript in the CNS, the dorsal vessel, abdominal dorsal epidermis, and prothoracic glands with associated fat body. Interestingly, transcript expression was also found in the female and male reproductive tissues. Rhopr-CRZR transcript was reduced after injection of dsCRZR into adult R. prolixus. In these insects, the basal heartbeat rate was reduced in vivo, and the increase in heartbeat frequency normally produced by CRZ on dorsal vessel in vitro was much reduced. No effect of dsCRZR injection was seen on ecdysis or coloration of the cuticle

Evaluating Voluntary Measures with Spillovers: The Case of Coal Combustion Products Partnership

Traditionally, voluntary measures have been evaluated using the same framework regardless of their structure. The framework assumes that the measure provides partners with a treatment (information, research support, etc) that will not be transferred to nonpartners. In this framework, a voluntary measure is said to be worthwhile if there are significant differences between the behavior of partners and non-partners, correcting for the potential endogeneity of becoming a partner. However, voluntary measures take many different forms; some which are expected to have information transfers (spillovers) to non-partners. The Coal Combustion Products Partnership (C2P2) is a voluntary program to increase the re-use of coal combustion products (CCP) using a structure that is likely to provide spillovers to non-partners. This paper evaluates C2P2 and tests whether program spillovers are affecting non-partners’ behavior. Results suggest that the traditional interpretation would find this program unsuccessful, however when spillovers are considered, evidence points to a successful program

Contract Parameters' Impacts on Coal Prices

The use of long-term contracts in the procurement of coal for electricity generation is common. The data that is observed from contracts and their transactions are from different levels of the pricing process. Contracts contain the parameters by which all future deliveries are structured, specifying the length of the agreement and acceptable coal attributes. Based on these parameters, a price is later determined for successive coal deliveries and the transaction occurs. This data structure fits well into multi-level models, where each level of the process is empirically estimated. A random intercept model is estimated where the first level is a hedonic model of coal prices. The contract that initiates the delivery is used to connect the two levels of the model. In the second level, contract coefficients from the first level are regressed on contract parameters to determine their impact on how coal is priced. Results find that many contract parameters are statistically significant in the price of coal

A framework for a joint hydro-meteorological-social analysis of drought

This article presents an innovative framework for analysing environmental governance challenges by focusing on their Drivers, Responses and Impacts (DRI). It builds on and modifies the widely applied Drivers, Pressures, States, Impacts and Responses (DPSIR) model. It suggests, firstly and most importantly, that the various temporal and spatial scales at which Drivers, Responses and Impacts operate should be included in the DRI conceptual framework. Secondly, the framework focuses on Drivers, Impacts and Responses in order to provide a parsimonious account of a drought system that can be informed by a range of social science, humanities and science data. ‘Pressures’ are therefore considered as a sub-category of ‘Drivers’. ‘States’ are a sub-category of ‘Impacts’. Thirdly, and most fundamentally in order to facilitate cross-disciplinary research of droughts, the DRI framework defines each of its elements, ‘Drivers’, ‘Pressures’, ‘States’, ‘Impacts’ and ‘Responses’ as capable of being shaped by both linked natural and social factors. This is different from existing DPSIR models which often see ‘Responses’ and ‘Impacts’ as located mainly in the social world, while ‘States’ are considered to be states within the natural environment only. The article illustrates this argument through an application of the DRI framework to the 1976 and 2003–6 droughts. The article also starts to address how - in cross-disciplinary research that encompasses physical and social sciences – claims about relationships between Drivers as well as Impacts of and Responses to drought over time can be methodologically justified. While the DRI framework has been inductively developed out of research on droughts we argue that it can be applied to a range of environmental governance challenges

Variability in coal prices: evidence from the U.S.

Monthly U.S. coal price time series data are tested to determine the persistence of shocks. The time series is then disaggregated by length of agreement to further explore the first and second moments of pricing behaviour. Results show that prices have a variance that changes over time and tend to be highly persistent. Prices from long-term transaction agreements tend to require more lags and have a higher degree of persistence

Contract Renegotiation and Rent Re-Redistribution: Who Gets Raked Over the Coals?

Policy shocks affect the rent distribution in long-term contracts, which can lead to such contracts being renegotiated. We seek an understanding of what aspects of contract design, in the face of a substantial policy shock, affect the propensity to renegotiate. We test our hypotheses using data on U.S. coal contracts after the policy shock of the 1990 Clean Air Act Amendments. This law altered the regulation of emissions of sulfur dioxide from coal-fired electric power plants, initiating a tradable permit system for a subset of coal-fired power plants which had previously been unregulated at the federal level. Contracts are divided into two categories, those that were renegotiated following the shock and those that were not and their characteristics are used to determine how they influence whether or not a contract was ultimately renegotiated. The number of years until the contract expires, a larger allowable sulfur content upper bound for plants regulated immediately by the tradable permit scheme, and the minimum quantity are all associated with a contract being renegotiated

Determinants of the green electricity tariff uptake in the UK

A number of countries offer domestic consumers the option of buying their electricity supply through a ‘green tariff’, whereby the supplier typically guarantees that all or part of the supply has been generated using renewable energy sources. Various studies have sought to identify variables describing and/or predicting why domestic consumers choose to purchase a green tariff. This study builds on previous work by reviewing the UK market in particular. Using data from the Understanding Society Survey (USS), a number of variables were tested for their predictive power. This included variables identified as statistically significant within other studies, and variables that – to the authors’ knowledge – have not been tested through other work. Results find that individuals in the highest income quartile, those with higher qualifications, those supporting the Green political party, those exhibiting strong environmental behaviour and those householdsnot in receipt of winter fuel payments were all more likely to have purchased green tariffs. Significant to a lesser degree were strong environmental attitudes and those households with some form of renewable energy technology installed

Can lobbying encourage abatement? Designing a new policy instrument

Taking a political economy perspective this paper proposes an alternative carbon abatement policy instrument with significant cant advantages over existing policy instruments. The key feature of the proposed carbon securities is that they entitle their owners to a fi xed proportion of ex ante unknown total emis-sions. The total level of carbon emissions is set by the political process after the carbon securities have been sold. A key benefit of the proposed carbon security is that it creates a group of stakeholders, whose interest is for a smaller level of emissions and which competes with industries that consume signifi cant amounts of carbon-based energy. The advantages over existing policy tools include an equilibrium carbon price closer to the level preferred by voters and a more predictable environmental policy in the presence of either climate or political uncertainty. (JEL: D72, Q54, Q58