The evolution and comparative neurobiology of endocannabinoid signalling

CB(1)- and CB(2)-type cannabinoid receptors mediate effects of the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide in mammals. In canonical endocannabinoid-mediated synaptic plasticity, 2-AG is generated postsynaptically by diacylglycerol lipase alpha and acts via presynaptic CB(1)-type cannabinoid receptors to inhibit neurotransmitter release. Electrophysiological studies on lampreys indicate that this retrograde signalling mechanism occurs throughout the vertebrates, whereas system-level studies point to conserved roles for endocannabinoid signalling in neural mechanisms of learning and control of locomotor activity and feeding. CB(1)/CB(2)-type receptors originated in a common ancestor of extant chordates, and in the sea squirt Ciona intestinalis a CB(1)/CB(2)-type receptor is targeted to axons, indicative of an ancient role for cannabinoid receptors as axonal regulators of neuronal signalling. Although CB(1)/CB(2)-type receptors are unique to chordates, enzymes involved in biosynthesis/inactivation of endocannabinoids occur throughout the animal kingdom. Accordingly, non-CB(1)/CB(2)-mediated mechanisms of endocannabinoid signalling have been postulated. For example, there is evidence that 2-AG mediates retrograde signalling at synapses in the nervous system of the leech Hirudo medicinalis by activating presynaptic transient receptor potential vanilloid-type ion channels. Thus, postsynaptic synthesis of 2-AG or anandamide may be a phylogenetically widespread phenomenon, and a variety of proteins may have evolved as presynaptic (or postsynaptic) receptors for endocannabinoids

Dividend and Share Changes: Is There a Financing Hierarchy?

The most widely accepted empirical dividend model is that proposed by Lintner, who argued that firms smooth dividends over time. Many theoretical dividend models, however, either predict that dividends should be highly variable, or at least offer no support for the smoothing hypothesis. We use a switching regression model to test the Lintner model against an alternative which allows dividend behavior to differ depending upon whether or not firms are issuing shares. We reject the Lintner model, finding no evidence of dividend smoothing when firms are not issuing shares, and a high negative dividend growth rate when firms are issuing shares. This description of dividend behavior suggests the existence of a financing hierarchy in that the marginal source of finance differs over time. To further explore the financing hierarchy, we estimate logit models which explain the decisions by firms to change dividends, and to issue or repurchase shares. The results are consistent with the existence of a financing hierarchy.

Inflation Target Transparency and the Macroeconomy

We quantify the effects of monetary policy transparency and credibility on macroeconomic volatility in an estimated model of the euro area economy. In our model, private agents are unable to distinguish between temporary shocks to the central bank’s monetary policy rule and persistent shifts in the inflation target, and therefore use optimal filtering techniques to construct estimates of the future monetary policy stance. We find that the macroeconomic benefits of credibly announcing the current level of the time-varying inflation target are reasonably small as long as private agents correctly understand the stochastic processes governing the inflation target and the temporary policy shock. If, on the other hand, private agents overestimate the volatility of the inflation target, the overall gains of announcing the target can be substantial. We also show that the central bank to some extent can help private agents in their learning process by responding more aggressively to deviations of inflation from the target.Credibility; Transparency; Inflation targeting; Imperfect information; Private sector learning

A Minimally-Invasive Procedure for Sexing Young Zebra Finches

Zebra finches have been widely used to study neurobiology underlying vocal development. Because only male zebra finches learn song, efficient developmental use of these animals requires early determination of sex at ages that precede maturation of secondary sex characteristics. We have developed a sex determination method that combines a forensics method of genomic DNA isolation (from very small blood samples) with PCR amplification from Z and W sex chromosomes (males are ZZ, females ZW). This combination results in a minimally-invasive yet highly reliable and convenient genotyping method. Originally published Journal of Neuroscience Methods, Vol. 164, No. 1, Aug 200

CB1 Cannabinoid Receptor Activation Dose-Dependently Modulates Neuronal Activity within Caudal but not Rostral Song Control Regions of Adult Zebra Finch Telencephalon

CB1 cannabinoid receptors are distinctly expressed at high density within several regions of zebra finch telencephalon including those known to be involved in song learning (lMAN and Area X) and production (HVC and RA). Because: (1) exposure to cannabinoid agonists during developmental periods of auditory and sensory-motor song learning alters song patterns produced later in adulthood and; (2) densities of song region expression of CB1 waxes-and-wanes during song learning, it is becoming clear that CB1 receptor-mediated signaling is important to normal processes of vocal development. To better understand mechanisms involved in cannabinoid modulation of vocal behavior we have investigated the dose-response relationship between systemic cannabinoid exposure and changes in neuronal activity (as indicated by expression of the transcription factor, c- Fos) within telencephalic brain regions with established involvement in song learning and/or control. In adults we have found that low doses (0.1 mg/kg) of the cannabinoid agonist WIN-55212-2 decrease neuronal activity (as indicated by densities of c-fos-expressing nuclei) within vocal motor regions of caudal telencephalon (HVC and RA) while higher doses (3 mg/kg) stimulate activity. Both effects were reversed by pretreatment with the CB1-selective antagonist rimonabant. Interestingly, no effects of cannabinoid treatment were observed within the rostral song regions lMAN and Area X, despite distinct and dense CB1 receptor expression within these areas. Overall, our results demonstrate that, depending on dosage, CB1 agonism can both inhibit and stimulate neuronal activity within brain regions controlling adult vocal motor output, implicating involvement of multiple CB1-sensitive neuronal circuits. Originally published Psychopharmacology, Vol. 199, No. 2, Aug 200

Empirical analysis for Distributed Energy Resources' impact on future distribution network

There has been a large body of statements claiming that the large scale deployment of Distributed Energy Resources (DERs) will eventually reshape the future distribution grid operation in various ways. Thus, it is interesting to introduce a platform to interpret to what extent the power system operation will be alternated. In this paper, quantitative results in terms of how the future distribution grid will be changed by the deployment of distributed generation, active demand and electric vehicles, are presented. The analysis is based on the conditions for both a radial and a meshed distribution network. The input parameters are based on the current and envisioned DER deployment scenarios proposed for Sweden.</p

High-spin structure in K-40

High-spin states of K-40 have been populated in the fusion-evaporation reaction C-12(Si-30,np)K-40 and studied by means of gamma-ray spectroscopy techniques using one triple-cluster detector of the Advanced Gamma Tracking Array at the Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro. Several states with excitation energy up to 8 MeV and spin up to 10(-) have been discovered. These states are discussed in terms of J = 3 and T = 0 neutron-proton hole pairs. Shell-model calculations in a large model space have shown good agreement with the experimental data for most of the energy levels. The evolution of the structure of this nucleus is here studied as a function of excitation energy and angular momentum. ©2012 American Physical SocietyWe would like to thank the Swedish National Infrastructure for Computing (SNIC) and the Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX) for the computer resources used in parts of the analysis.This work was financed by EURONS AGATA (Contract no. 506065-R113), the Swedish Research Council under contracts 621-2008-4163, 621-2011-4522, 822-2005-3332 and 821-2010-6024, the Japan Society for the Promotion of Science (JSPS) Kakenhi Grant No. 23·01752, Ankara University (BAP Project number 05B4240002), the Polish Ministry of Science and Higher Education under grants number DPN/N190/AGATA/2009 and N N202 073935, the German BMBF under Grants 06K-167, 06KY205I and 06KY9136I, the Knut and Alice Wallenberg Foundation contract number 2005.0184 and STFC (UK). A. Gadea and E. Farnea acknowledge the support of MICINN, Spain, and INFN, Italy through the AIC-D-2011-0746 bilateral action. A. Gadea’s activity has been partially supported by the Generalitat Valenciana, Spain, under grant PROMETEO/2010/101. A. Gadea, A. Jungclaus, A. Poves and B. Quintana acknowledge support from the MICINN, Spain, under grant FPA2011-29854. A. Pove is partially supported by the Comunidad de Madrid (Spain) (HEPHACOS S2009-ESP-1473). G. Jaworski acknowledges the support of the Center for Advanced Studies of Warsaw University of Technology. B. Cederwall acknowledge the support of the Göran Gustafsson FoundationPeer Reviewe

Playing Multiple Positions: Student-Athlete Identity Salience and Conflict

Student-athletes enact dual roles, as students and athletes, and hold corresponding identities. The salience of these identities and conflict between them have implications for student-athlete wellness. The purpose of this study was to (a) gain insight into organizational and individual characteristics associated with identity salience, by examining student-athletes across universities; and (b) shed light on situations of identity salience and conflict for student-athletes. We conducted a survey study of student-athletes across 17 universities that captured both quantitative and qualitative data. Our results reveal a relationship between identity salience and individual performance (academic and athletic) and university ranking. Further, we found an interaction between athlete and student identity salience, such that identifying strongly as a student, athlete, both, or neither has implications for conflict. Finally, by unpacking situations of identity salience and conflict, we show similarities and differences across student-athletes’ experiences. This study has implications for universities and athletic departments

Crystal structure of 1-butyl-2,3-di-methylimidazolium dicarba-7,8-nido-undecaborate

AL thanks Professor Maitland Jones for the generous donation of the starting orthocarborane stock and Dr John Holbrey for the supply of imidazolium halide reagents. The research support by ACS PRF and Cottrell College awards (44692.01-GB and CC6755) is gratefully acknowledged.Peer reviewedPublisher PD

Searches for New Quarks and Leptons Produced in Z-Boson Decay

We have searched for events with new-particle topologies in 390 hadronic Z decays with the Mark II detector at the SLAC Linear Collider. We place 95%-confidence-level lower limits of 40.7 GeV/c^2 for the top-quark mass, 42.0 GeV/c^2 for the mass of a fourth-generation charge - 1/3 quark, and 41.3 GeV/c^2 for the mass of an unstable Dirac neutral lepton