The Irish Electricity Market: New Regulation to Preserve Competition. ESRI Research Notes 2015/1/1

In the electricity sector there are two different markets: the wholesale (or spot) market, in which electricity generators generate and sell electricity at a new price every half hour, and the retail market, in which electricity supply companies sell electricity to the final consumers. Supply companies tend not to change the price they charge their consumers very frequently, and so these companies typically enter into longer-term contracts for electricity with generators to avoid the risks they would face if they bought at a new price every half hour. Internationally, many electricity markets also include a specific capacity payment mechanism, which ensures generators receive sufficient revenue to cover their fixed costs, thereby incentivising investment

Competition and the Single Electricity Market: Which Lessons for Ireland?. ESRI WP497. March 2015

This paper examines the redesign of the Irish Single Electricity Market in order to comply with the European Target Model for electricity. In particular, this work focuses on the challenges raised by the high concentration in the generation sector which exists in the Irish electricity market. We examine the theoretical and empirical conditions under which forward markets promote competition in the spot and retail markets; in addition, we investigate the impact of concentration in the market on the new capacity payment mechanism. In order to ensure a competitive outcome for consumers, the regulatory authorities should continue to regulate the directed forward contracts made by the dominant firm; moreover, our analysis suggests that the regulator should extend regulation to the price and quantity which the dominant firm bids for holding new reliability options

Topology and quantum states: The electron-monopole system

This paper starts by describing the dynamics of the electronmonopole system at both classical and quantum level by a suitable reduction procedure. This suggests, in order to realise the space of states for quantum systems which are classically described on topologically non-trivial configuration spaces, to consider Hilbert spaces of exterior differential forms. Among the advantages of this formulation, we present—in the case of the group SU(2), how it is possible to obtain all unitary irreducible representations on such a Hilbert space, and how it is possible to write scalar Dirac-type operators, following an idea by K¨ahler

Ovariectomy impairs socio-cognitive functions in dogs

Recent studies have underlined the effect of ovariectomy on the spatial cognition of female dogs, with ovariectomized dogs showing a clear preference for an egocentric rather than an allocentric navigation strategy whereas intact females did not show preferences. Intact females had better performances than gonadectomized females in solving a learning task in a maze. Ovariectomy also affects socio-cognitive abilities, reducing the dog's level of attention on the owner. We tested dogs (Canis lupus familiaris) in the object choice task paradigm to assess whether an ovariectomy could impair females' ability to follow human signals. Forty pet dogs (18 intact females (IF) and 22 gonadectomized females (GF)) were tested in the object choice task paradigm using the human proximal pointing gesture. For the analysis, the frequency of correct, wrong and no-choices was collected; moreover, the latency of the correct choices was also considered. The IF group followed the pointing gestures more often than the GF group and with a lower latency, whereas a significantly higher no-choice frequency was recorded for the GF group. These results show a detrimental effect of ovariectomy on dogs' socio-cognitive skills related to the responsiveness to human pointing gestures

N-Methyl-d-aspartate Receptor Stimulation Activates Tyrosinase and Promotes Melanin Synthesis in the Ink Gland of the Cuttlefish Sepia officinalis through the Nitric Oxide/cGMP Signal Transduction Pathway: A NOVEL POSSIBLE ROLE FOR GLUTAMATE AS PHYSIOLOGIC ACTIVATOR OF MELANOGENESIS *

Abstract The tyrosinase-catalyzed conversion of l-tyrosine to melanin represents the most distinctive biochemical pathway in the ink gland of the cuttlefishSepia officinalis; however, the molecular mechanisms underlying its activation have remained so far largely uncharted. In this paper we demonstrate for the first time thatl-glutamate can stimulate tyrosinase activity and promote melanin synthesis in Sepia ink gland via theN-methyl-d-aspartate (NMDA) receptor/NO/cGMP signal transduction pathway. Incubation of intact ink glands with either l-glutamate or NMDA resulted in an up to 18-fold increase of tyrosinase activity and a more than 6-fold elevation of cGMP levels. Comparable stimulation of tyrosinase was induced by an NO donor and by 8-bromo-cGMP. An NMDA receptor antagonist, NO synthase (NOS) inhibitors, and a guanylate cyclase blocker suppressed NMDA-induced effects. Immunohistochemical evidence indicated that enhanced cGMP production was localized largely in the mature part of the ink gland. Increased de novo synthesis of melanin was demonstrated in NMDA- and NO-stimulated ink glands by a combined microanalytical approach based on spectrophotometric determination of pigment levels and high performance liquid chromatography quantitation of pyrrole-2,3,5-tricarboxylic acid, a specific melanin marker, in melanosome-containing fractions. These results fill a longstanding gap in the understanding of the complex biochemical mechanisms underlying activation of melanogenesis in the mature ink gland cells of S. officinalis and disclose a novel physiologic role of the excitatory neurotransmitter glutamate mediated by the NMDA receptor/NO/cGMP signaling pathway

Fixation of genetic variation and optimization of gene expression: The speed of evolution in isolated lizard populations undergoing Reverse Island Syndrome

The ecological theory of island biogeography suggests that mainland populations should be more genetically divergent from those on large and distant islands rather than from those on small and close islets. Some island populations do not evolve in a linear way, but the process of divergence occurs more rapidly because they undergo a series of phenotypic changes, jointly known as the Island Syndrome. A special case is Reversed Island Syndrome (RIS), in which populations show drastic phenotypic changes both in body shape, skin colouration, age of sexual maturity, aggressiveness, and food intake rates. The populations showing the RIS were observed on islets nearby mainland and recently raised, and for this they are useful models to study the occurrence of rapid evolutionary change. We investigated the timing and mode of evolution of lizard populations adapted through selection on small islets. For our analyses, we used an ad hoc model system of three populations: wild-type lizards from the mainland and insular lizards from a big island (Capri, Italy), both Podarcis siculus siculus not affected by the syndrome, and a lizard population from islet (Scopolo) undergoing the RIS (called P. s. coerulea because of their melanism). The split time of the big (Capri) and small (Scopolo) islands was determined using geological events, like sea-level rises. To infer molecular evolution, we compared five complete mitochondrial genomes for each population to reconstruct the phylogeography and estimate the divergence time between island and mainland lizards. We found a lower mitochondrial mutation rate in Scopolo lizards despite the phenotypic changes achieved in approximately 8,000 years. Furthermore, transcriptome analyses showed significant differential gene expression between islet and mainland lizard populations, suggesting the key role of plasticity in these unpredictable environments

Cognitive stimulation induces differential gene expression in octopus vulgaris: The key role of protocadherins

Octopuses are unique invertebrates, with sophisticated and flexible behaviors controlled by a high degree of brain plasticity, learning, and memory. Moreover, in Octopus vulgaris, it has been demonstrated that animals housed in an enriched environment show adult neurogenesis in specific brain areas. Firstly, we evaluated the optimal acclimatization period needed for an O. vulgaris before starting a cognitive stimulation experiment. Subsequently, we analyzed differential gene expression in specific brain areas in adult animals kept in tested (enriched environment), wild (naturally enriched environment), and control conditions (unenriched environment). We selected and sequenced three protocadherin genes (PCDHs) involved in the development and maintenance of the nervous system; three Pax genes that control cell specification and tissue differentiation; the Elav gene, an earliest marker for neural cells; and the Zic1 gene, involved in early neural formation in the brain. In this paper, we evaluated gene expression levels in O. vulgaris under different cognitive stimulations. Our data shows that Oct-PCDHs genes are upregulated in the learning and lower motor centers in the brain of both tested and wild animals (higher in the latter). Combining these results with our previous studies on O. vulgaris neurogenesis, we proposed that PCDH genes may be involved in adult neurogenesis processes, and related with their cognitive abilities

Prostasome-like particles in stallion semen.

Human semen contains membranous vesicles called prosta- somes. They are secreted by the prostate gland and contain large amounts of cholesterol, sphingomyelin, and Ca2. Prostasomes enhance the motility of ejaculated spermatozoa and are in- volved in a number of additional biological functions. No prostasome-like vesicles have been described in horse se- men up to now. We have demonstrated the presence of pros- tasome-like vesicles in the equine semen and characterized them as to size, morphology, and lipid composition; we have found that they are similar to human prostasomes in many re- spects. We propose that these vesicles might be important for the fecundity of horse semen. This is of interest since the success of artificial insemination is limited by the fact that stallion sperm barely survive cryopreservation