Carleton University

About: Carleton University is a education organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Context (language use). The organization has 15852 authors who have published 39650 publications receiving 1106610 citations.

Measurement of the muon reconstruction performance of the ATLAS detector using 2011 and 2012 LHC proton–proton collision data

Abstract: This paper presents the performance of the ATLAS muon reconstruction during the LHC run with pp collisions at root s = 7-8 TeV in 2011-2012, focusing mainly on data collected in 2012. Measurements ...

Search for dark matter candidates and large extra dimensions in events with a jet and missing transverse momentum with the ATLAS detector

Abstract: A search for new phenomena in events with a high-energy jet and large missing transverse momentum is performed using data from proton-proton collisions at root s = 7 TeV with the ATLAS experiment at the Large flatiron Collider. Four kinematic regions are explored using a dataset corresponding to an integrated luminosity of 4.7 fb(-1). No excess of events beyond expectations from Standard Model processes is observed, and limits are set on large extra dimensions and the pair production of dark matter particles.

Boldness and behavioral syndromes in the bluegill sunfish, Lepomis macrochirus

Abstract: In recent years, evidence for interindividual variation in "personality" within animal populations has been accumulating. Personality is defined as consistency in an individual's behavioral responses over time and/or across situations. One personality trait that has potentially far-reaching implications for behavioral ecology, and may provide insight into the mechanisms by which consistent behavioral correlations arise, is that of boldness. Boldness is defined as the tendency of an individual to take risks and be exploratory in novel contexts. Using the framework of behavioral syndromes, we tested for individual differences in boldness in the laboratory among field-caught juvenile bluegill sunfish (Lepomis macrochirus) within and across the contexts of exploratory behavior, activity, and risk taking (e.g., antipredator) behavior. After such testing, individuals were tagged and returned to their lake of origin as part of a mark--recapture study testing for the repeatability of individual differences in boldness. Here, we report strong and consistent individual differences in boldness within and across all 3 behavioral contexts. Additionally, we observed that at least some boldness behaviors were repeatable after a 1--3 month recapture period. This study provides novel evidence for a boldness syndrome in sunfish, as well as insight into how behavioral types (e.g., shy/bold) may evolve and be maintained in natural populations. Copyright 2009, Oxford University Press.

Disruption of cocaine and heroin self-administration following kainic acid lesions of the nucleus accumbens

Abstract: In previous experiments we have demonstrated that bilateral infusions of 6-hydroxydopamine (6-OHDA) into the nucleus accumbens result in a drastic reduction in the rate of cocaine self-administration. If this effect is due to the destruction of a presynaptic dopaminergic element in this nucleus, then selective removal of the postsynaptic neuron should also disrupt cocaine self-administration. This hypothesis was tested using the neurotoxin kainic acid. Bilateral kainic acid infusions into the nucleus accumbens resulted in a drastic destruction of cell bodies yet did not damage catecholamine innervation in areas anterior to the accumbens. The effects of these kainic acid infusions were evaluated in rats that had previously acquired cocaine self-administration behavior. These lesions were found to severely disrupt cocaine intake and the degree of damage produced in the accumbens was found to correlate (r = 0.88) with postlesion cocaine intake. These lesions were additionally found to disrupt apomorphine and heroin self-administration. The possibility that these results are due to destruction of systems necessary for stimulant and opiate reward is discussed.