Morphine-induced modification of quinine palatability: Effects of multiple morphine-quinine trials

Contemporary research investigating the effects of opiate receptor agonists and antagonists indicates a role for endorphinergic mechanisms in the control of consummatory behaviours. One way in which opiates may exert an effect on feeding is by altering the hedonic properties or palatability of food and drink. Investigations of the role of palatability in the effect of opiates on feeding and drinking have primarily considered the effect of single exposures to opiates. Recognizing that chronic exposure to opiates may result in the development of tolerance to their palatability-altering properties, the taste reactivity test, a direct measure of the hedonic properties of a tastant, was used to assess the ability of morphine to modify the palatability of a bitter quinine solution across eight conditioning trials (Experiment 1). Morphine consistently reduced aversive reactions to the quinine solution across all eight conditioning trials, but tolerance did not develop to this effect. In tests for conditioned modification of quinine palatability, administered after the third and the eighth conditioning trial, quinine elicited conditioned attenuation of aversive reactions in the Contingent, but not in the Noncontingent group. Hence, there was evidence of drug-similar conditioned responses suggesting that an association had been established between the effect of morphine on palatability, and the taste of quinine. In order to determine how rapidly this association was established, a second experiment was conducted whereby subjects received a single injection of morphine 30 min prior to a 10 min infusion of quinine. The results of this experiment indicated that a single exposure is insufficient for the formation of an association between the effect of morphine on palatability, and the taste of quinine. In summary, therefore, tolerance did not develop to the ability of morphine to attenuate aversive reactions to the taste of quinine. Furthermore, quinine elicited conditioned attenuation of aversive reactions when assessed during drug-free tests, suggesting that the palatability of quinine was conditionally altered in a positive direction following its association with morphine

Meeting of the MINDS: an information retrieval research agenda

Since its inception in the late 1950s, the field of Information Retrieval (IR) has developed tools that help people find, organize, and analyze information. The key early influences on the field are well-known. Among them are H. P. Luhn's pioneering work, the development of the vector space retrieval model by Salton and his students, Cleverdon's development of the Cranfield experimental methodology, Spärck Jones' development of idf, and a series of probabilistic retrieval models by Robertson and Croft. Until the development of the WorldWideWeb (Web), IR was of greatest interest to professional information analysts such as librarians, intelligence analysts, the legal community, and the pharmaceutical industry

Crime Script Sequencing: An optimal forensic combination for cold case analysis

Criminal cases go cold when investigative leads or forensic testing does not lead to a successful arrest. In these cases, investigators are often keen to use novel methods to derive fresh ideas or insights. Recently, academics from a range of fields, including Psychology, Criminology, and Forensic Sciences have developed a range of new methods and tests to assist with police investigations. The current paper outlines a novel approach to assisting with police cold case investigations: Crime Script Sequencing. The new method combines two leading temporal methods, Crime Script Analysis and Behaviour Sequence Analysis. A real-world cold case, the bombing of Canadian Pacific Airlines Fight 21, is presented and analysed using Crime Script Sequencing to offer readers a guide of how to use the method for other investigations. Impacts, insights, and potential future developments of the method are outlined

DC modulation noise in clustered particulate media

Mallinson’s theory of recording media noise is extended to ensembles where the particles have an easy axis distribution or are clustered. The effect of clusters is that there is a critical value of packing fraction at which noise in the demagnetised state switches to a minimum. Comparison is made with measurements of DC modulation noise in double layer MP tape

The Stellar-Disk Electric (Short) Circuit: Observational Predictions for a YSO Jet Flow

We discuss the star-disk electric circuit for a young stellar object (YSO) and calculate the expected torques on the star and the disk. We obtain the same disk magnetic field and star-disk torques as given by standard magnetohydrodynamic (MHD) analysis. We show how a short circuit in the star-disk electric circuit may produce a magnetically-driven jet flow from the inner edge of a disk surrounding a young star. An unsteady bipolar jet flow is produced that flows perpendicular to the disk plane. Jet speeds of order hundreds of kilometres per second are possible, while the outflow mass loss rate is proportional to the mass accretion rate and is a function of the disk inner radius relative to the disk co-rotation radius.Comment: 6 pages, 8 figures, Accepted for publication in Astrophysics & Space Scienc

Large Kinetic Power in FRII Radio Jets

We investigate the total kinetic powers (L_{j}) and ages (t_{age}) of powerful jets of four FR II radio sources (Cygnus A, 3C 223, 3C 284, and 3C 219) by the detail comparison of the dynamical model of expanding cocoons with observed ones. It is found that these sources have quite large kinetic powers with the ratio of L_{j} to the Eddington luminosity (L_{Edd}) resides in $0.02 <L_{j}/L_{Edd} <10$. Reflecting the large kinetic powers, we also find that the total energy stored in the cocoon (E_{c}) exceed the energy derived from the minimum energy condition (E_{min}): $2< E_{c}/E_{min} <160$. This implies that a large amount of kinetic power is carried by invisible components such as thermal leptons (electron and positron) and/or protons.Comment: 5 pages, accepted for publication in Astrophysics and Space Scienc

Multiplayer Cost Games with Simple Nash Equilibria

Multiplayer games with selfish agents naturally occur in the design of distributed and embedded systems. As the goals of selfish agents are usually neither equivalent nor antagonistic to each other, such games are non zero-sum games. We study such games and show that a large class of these games, including games where the individual objectives are mean- or discounted-payoff, or quantitative reachability, and show that they do not only have a solution, but a simple solution. We establish the existence of Nash equilibria that are composed of k memoryless strategies for each agent in a setting with k agents, one main and k-1 minor strategies. The main strategy describes what happens when all agents comply, whereas the minor strategies ensure that all other agents immediately start to co-operate against the agent who first deviates from the plan. This simplicity is important, as rational agents are an idealisation. Realistically, agents have to decide on their moves with very limited resources, and complicated strategies that require exponential--or even non-elementary--implementations cannot realistically be implemented. The existence of simple strategies that we prove in this paper therefore holds a promise of implementability.Comment: 23 page

Predicting university performance in psychology: the role of previous performance and discipline-specific knowledge

Recent initiatives to enhance retention and widen participation ensure it is crucial to understand the factors that predict students' performance during their undergraduate degree. The present research used Structural Equation Modeling (SEM) to test three separate models that examined the extent to which British Psychology students' A-level entry qualifications predicted: (1) their performance in years 1-3 of their Psychology degree, and (2) their overall degree performance. Students' overall A-level entry qualifications positively predicted performance during their first year and overall degree performance, but negatively predicted their performance during their third year. Additionally, and more specifically, students' A-level entry qualifications in Psychology positively predicted performance in the first year only. Such findings have implications for admissions tutors, as well as for students who have not studied Psychology before but who are considering applying to do so at university

Sonoluminescence, shock waves, and micro-thermonuclear fusion

We have performed numerical hydrodynamic simulations of the growth and collapse of a sonoluminescing bubble in a liquid. Our calculations show that spherically converging shock waves are generated during the collapse of the bubble. The combination of the shock waves and a realistic equation of state for the gas in the bubble provides an explanation for the measured picosecond optical pulse widths and indicates that the temperatures near the center of the bubble may exceed 3O eV. This leads naturally to speculation about obtaining micro-thermonuclear fusion in a bubble filled with deuterium (D{sub 2}) gas. Consequently, we performed numerical simulations of the collapse of a D{sub 2} bubble in D{sub 2}0. A pressure spike added to the periodic driving amplitude creates temperatures that may be sufficient to generate a very small, but measurable number of thermonuclear D-D fusion reactions in the bubble