459 research outputs found
A Special Issue on the Roles of Dopamine in Neural Circuits, Genetics, and Behavior
No full textOver the past 80 years, research on dopamine has undergone significant evolution, reshaping our understanding of its roles in the brain and the body [...
That shrewd yet visionary voice.
No full textIDRC governor. Introductory speech given for Lester B. Pearson, former politician and diplomat of Canada - the author discusses Pearson's desire for world peace
Seize the day Lester B. Pearson and crisis diplomacy
No full textIn this uniquely insightful and informed account of Lester B. Pearson's foreign policy in the year 1948-1957, his son Geoffrey Pearson places the "Golden Age" of Canadian diplomacy in perspective. Holding the necessary balance between nationalism and realism in a particularly unstable time emerges as Pearson's overriding achievement as Secretary of State for External Affairs. It was a time when Canadian influence was felt around the world, and it culminated with a Nobel Peace Prize for Pearson. The author examines his father's politics in the context of Cold War stand-off, relations with the United States, the pressures for collective security, and the threat of nuclear war. Research into cabinet documents, combined with more personal sources, provides an especially strong picture of the Pearson legacy and its future implications for Canadian foreign policy
Narrative prose generation
No full textAbstractNarrative generation has historically suffered from poor writing quality, stemming from a narrow focus on story grammars and plot design. Moreover, to-date natural language generation systems have not been capable of faithfully reproducing either the variety or complexity of naturally occurring narratives. In this article we first propose a model of narrative derived from work in narratology and grounded in observed linguistic phenomena. Next we describe the Author architecture for narrative generation and an end-to-end implementation of the Author model in the StoryBook narrative prose generation system. Finally, we present a formal evaluation of the narratives that StoryBook produces
Saga of the Whispering Hills - 060
No full textPhotograph - Cast members Lester and Margaret Mapp. Saga of the Whispering Hills, presented by the Athabasca Players for the 75th Anniversary of Athabasca, Albert
Athabasca's 50th Anniversary Celebration
No full textPhotograph - Contestants in the Beard contest at Athabasca's 50th Anniversary Celebration, Athabasca, Alberta. Back row: Steve Berezan, Tony Schinkinger, Walt Talmey, Melvyn Smith, Buster Bissell, Buster Overacher, Nap Gullion, Albert Bury, Rev Jack Gibbons, Glen Osment. Front row: Lester Girden, Allan Minns, Bill Baerwald, K. Grandlund, Ken Jones, Earl Schmelzle, and Paul Harm
Saga of the Whispering Hills - 084
No full textPhotograph - Cast members in the Ethnic Parade: Charles and Rose-Alice Patry (French), Lester and Margaret Mapp (American Negro), Alec Hay and Joan Knight (Scottish). Saga of the Whispering Hills, presented by the Athabasca Players for the 75th Anniversary of Athabasca, Alberta
Acetylcholine-Dopamine Interactions in the Pathophysiology and Treatment of CNS Disorders
No full textDopaminergic neurons in the substantia nigra pars compacta and ventral tegmental area of the midbrain form the nigrostriatal and mesocorticolimbic dopaminergic pathways that, respectively, project to dorsal and ventral striatum (including prefrontal cortex). These midbrain dopaminergic nuclei and their respective forebrain and cortical target areas are well established as serving a critical role in mediating voluntary motor control, as evidenced in Parkinson\u27s disease, and incentive-motivated behaviors and cognitive functions, as exhibited in drug addiction and schizophrenia, respectively. Although it cannot be disputed that excitatory and inhibitory amino acid-based neurotransmitters, such as glutamate and GABA, play a vital role in modulating activity of midbrain dopaminergic neurons, recent evidence suggests that acetylcholine may be as important in regulating dopaminergic transmission. Midbrain dopaminergic cell tonic and phasic activity is closely dependent upon projections from hindbrain pedunculopontine and the laterodorsal tegmental nuclei, which comprises the only known cholinergic inputs to these neurons. In close coordination with glutamatergic and GABAergic activity, these excitatory cholinergic projections activate nicotinic and muscarinic acetylcholine receptors within the substantia nigra and ventral tegmental area to modulate dopamine transmission in the dorsal/ventral striatum and prefrontal cortex. Additionally, acetylcholine-containing interneurons in the striatum also constitute an important neural substrate to provide further cholinergic modulation of forebrain striatal dopaminergic transmission. In this review, we examine neurological and psychopathological conditions associated with dysfunctions in the interaction of acetylcholine and dopamine and conventional and new pharmacological approaches to treat these disorders. © 2010 Blackwell Publishing Ltd
Age-Dependent Effects of Social Isolation on Behaviors Related to Anxiety and Addiction in Mice
No full textMuscarinic receptor blockade in the ventral tegmental area attenuates cocaine enhancement of laterodorsal tegmentum stimulation-evoked accumbens dopamine efflux in the mouse
No full textThe reinforcing properties of cocaine have been related to increased extracellular concentrations of dopamine in the nucleus accumbens (NAc). M5 muscarinic acetylcholine receptors (mAChRs) on dopamine cells in the ventral tegmental area (VTA) facilitate mesoaccumbens dopamine transmission and are critically involved in mediating natural and drug reinforcement. We investigated the effects of pharmacological blockade of mAChRs in the VTA on cocaine\u27s ability to enhance electrically evoked NAc dopamine efflux. Using fixed potential amperometry together with carbon fiber recording microelectrodes positioned in the NAc core, we quantified dopamine oxidation currents (dopamine efflux) evoked by brief stimulation (15 monophasic pulses at 50 Hz every 30 s) of the laterodorsal tegmentum (LDT) in urethane (1.5 g/kg, i.p.) anesthetized mice. Compared to predrug baseline responses, cocaine (5 or 10 mg/kg, i.p.) dose-dependently enhanced LDT stimulation-evoked NAc dopamine efflux, whereas the nonsubtype selective mAChR antagonist scopolamine (10 μg/0.5 μl) microinfused into the VTA diminished LDT-evoked NAc dopamine efflux. Preinfusion of scopolamine into the VTA diminished the facilitatory actions of cocaine on LDT stimulation-evoked NAc dopamine efflux, and when infused at the peak effect of cocaine attenuated LDT-evoked dopamine efflux to below predrug baseline levels. These findings suggest that LDT cholinergic inputs to dopamine neurons in the VTA, via activation of mAChRs (probably of the M5 subtype), are involved in modulating the facilitatory effects of cocaine on NAc dopamine neurotransmission. They also suggest that the development of antagonists aimed at selectively disrupting M5 receptor function may be valuable in reducing abuse liability of psychostimulants. © 2009 Wiley-Liss, Inc
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