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Motor deficits in the McGill-R-Thy1-APP transgenic rat model of Alzheimer’s Disease
No full textThe McGill-R-Thy1-APP rat is a transgenic model of Alzheimer’s Disease (AD) which expresses APP with two mutations found in cases of familial AD, resulting in the development of amyloid pathology and cognitive deficits. Motor deficits are common symptoms of AD, emerging early in the disease, and are correlated with AD neuropathology and cognitive symptoms. This study evaluated heterozygous and homozygous McGill-R-Thy1-APP rats and their wildtype littermates for spontaneous alternation and locomotion in the T and Y mazes, and motor behaviour on an accelerating rotarod. Because rats often jumped off the rotarod, the maximum latency to fall across trials was examined. We found no genotype or sex effects in spontaneous alternation in either maze, nor a significant correlation of spontaneous alternation behaviour between the mazes. Female rats travelled greater distances than male rats in both mazes. While there was no genotype effect in the T maze on distance travelled, in the Y maze the hemizygous rats travelled shorter distances than the wildtype rats, while the homozygous rats travelled greater distances. There was a significant correlation between the distances travelled in each maze. Both heterozygous and homozygous rats performed worse than their wildtype littermates on the rotarod, while heavier rats performed worse than lighter rats, and female rats performed worse than male rats once their differences in weights were accounted for. These findings support the continued use of these rats as a model of AD and highlight the need to consider the possible confounding effect motor impairments have on other behavioural tests
Replication Data for: Terrestrial emergence reflects lower thermal preferences in the mangrove rivulus (Kryptolebias marmoratus)
No full textMany fishes exploit the terrestrial environment. Some of these amphibious species use it as an ecological release, others for feeding, while others use land to escape aquatic stressors. Another hypothesis is that amphibious fishes leave water to thermoregulate, but there is little corroborating data. One of the most intriguing fish that emerges onto land is the mangrove rivulus (Kryptolebias marmoratus), which can survive on land for up to 75 days. The mangrove rivulus emerges to escape from warm water and initially benefits from enhanced evaporative cooling on land. However, emergence imposes an immediate hypoxemia due to reduced gas exchange over the gills and an accumulation of CO2 that impairs Hb-O2 binding. In other ectothermic species, hypoxia is known to decrease thermal preference. Before physiological acclimation restores respiratory function, it is therefore plausible that fish that have emerged onto land will seek cooler temperatures beyond what is achieved by simple evaporative cooling. To test this idea, two strains of laboratory-raised mangrove rivulus were placed in a thermal gradient that provided the option of land and water to determine how their preferred temperature was informed by choice of the surrounding environment. We hypothesized that selecting land would be associated with anapyrexia, or a purposeful selection of lower temperatures. In trials where thermal gradients were provided in aquatic, terrestrial, or combined settings, mangrove rivulus selected cooler temperatures only when on land. These findings support the premise that terrestrial emergence serves an active thermoregulatory strategy
Replication Data for: Stability in Cognitive and Behavioural Performance Varies Between Dog Breed Clades
No full textThe existence and stability of breed-specific cognitive and behavioural profiles remain a topic of ongoing debate. It is not yet clear whether the observed behavioural differences between dog breeds persist consistently over time, and whether the ability to maintain performance on a previously learned behaviour potentially confers differential advantages across breed clades.
Using a structured hand-touch learning task, discrimination and reversal learning performance, along with perseverance, and emotionality were assessed in 105 dogs from four breed clades across two testing occasions, while controlling for reward responsiveness, demographic factors, and relevant training history. Perseverance appeared to be a relatively stable trait, whereas discrimination and reversal learning performance seemed to improve across time. The extent of change in performance varied across breed clades, suggesting that breed-specific cognitive profiles may shape behavioural and learning dynamics over time.
Initial differences across breed clades in the reversal learning performance were not maintained upon re-exposure to the task, likely due to increased individual variability. In contrast, differences across breed clades in the discrimination learning performance emerged only in the second testing occasion. Thus, depending on the cognitive capacity being assessed, repeated exposure may either obscure or facilitate the expression of underlying breed-specific performance patterns. Furthermore, although the average emotionality decreased, emotionality changes did not consistently align with breed clades’ performance improvement, which may suggest a potential dissociation between cognitive performance and emotional reactivity in some breed clades. Where each breed falls within the cognitive stability-flexibility continuum requires further investigation
Replication Data for: Ammonia variability and trends from globally distributed FTIR measurements and model simulations
No full textThis dataset contains ammonia (NH3) total columns used in 'Ammonia variability and trends from globally distributed FTIR measurements and model simulations' by Herrera et al. (submitted, 2025). The NH3 total columns are in molecules cm-2, and were retrieved from mid-infrared spectroscopic solar absorption measurements made by ground-based Fourier transform infrared (FTIR) spectrometers at 22 sites. These sites are globally distributed in both hemispheres from 45°S to 80°N, with most of them affiliated with the Network for the Detection of Atmospheric Composition Change (NDACC)
Replication Data and Code for: Privacy Concerns in Insurance Markets: Implications for Market Equilibria and Customer Utility
No full textThe data and programs replicate figures from "Privacy Concerns in Insurance Markets: Implications for Market Equilibria and Customer Utility", by Irina Gemmo, Mark J. Browne, and Helmut Gründl. Please see the ReadMe file for additional details
Scenario 69
No full textPart of the Virtu-WIL project. See https://www.collegesinstitutes.ca/what-we-do/canadian-partnerships/virtu-wil/ for more details on this. Nursing case, post-operative complications.
Lors de la simulation virtuelle suivante, vous interagirez avec des personnages et dans une situation basée sur des situations cliniques réelles. La simulation virtuelle favorise un environnement d'engagement actif dans un espace sécuritaire. En tant que créateurs de la simulation virtuelle, nous avons fait le maximum pour rendre la simulation aussi réelle que possible. Nous reconnaissons que certains aspects ne sont pas réalistes. En tant qu'apprenants, nous vous demandons de vous engager dans la simulation et de considérer les membres de l'équipe soignante ainsi que le patient et sa famille, comme étant réels. Votre engagement dans l’expérience de simulation virtuelle permettra d’optimiser vos apprentissages
Exploring dairy heifers' consistency in social motivation in the absence or presence of conspecifics
No full textWe examined the consistency of heifers’ (n=36) sociability in the absence and presence of conspecifics. We applied standard animal personality tests to measure social motivation during social isolation. Additionally, we developed two novel test paradigms designed to quantify heifers’ willingness to trade off access to conspecifics in exchange for feed, thus measuring social motivation within a social context. In our distribution test, groups of three dairy heifers (n=12) could freely move between two feed troughs where grain was provided at two rates, with one providing twice as much feed as the other. Time feeding alone in the distribution test varied among heifers from 0 to 56.6 % of the time; this variation was weakly associated with differences in sociability as assessed by the time animals took to return to peers following social isolation, but not with heifers’ willingness to leave peers to access grain when tested in an alternative social-feed trade-off test. Our findings suggest that different measures of social motivation are not necessarily consistent, challenging the assumption that sociability is a stable personality trait in cattle. Instead, we propose to regard sociability as a ‘behavioural consequence’ resulting from the combined effects of internal characteristics (e.g., other personality traits such as fearfulness) and external factors (e.g., testing environment) at the time of evaluation
Circadian responses to non-photic treatments in BTBR mice
No full textThe BTBR T+ Itpr3tf/J mouse (BTBR) differs from C57BL/5 mice in various circadian parameters, including freerunning period (FRP), circadian responses to light, and prominent circadian responses to scheduled feeding. The circadian system is also sensitive to a host of non-photic cues, which can modify and reset freerunning rhythms as well as modulate responses to other zeitgebers such as light. Here we examine how the BTBR mouse responds to various non-photic treatments. Because activity levels can modulate the FRP, we first examined if the shorter FRP of BTBR mice resulted from their higher activity levels. While overall activity was lower when housed without a running wheel, this did not significantly alter their FRP. When housed in constant light, exposure to a 6h dark pulse improved the quality of the locomotor rhythms for both BTBR and C57 mice. BTBR mice had significantly smaller phase shifts to midday treatments with either a 3h sleep deprivation procedure or an injection of the serotonin 1A/7 receptor agonist (±) 8-OH-DPAT than did the comparison C57BL/6J strain. However, BTBR mice did exhibit larger responses to midday refeeding pulses following 18h food deprivation. Their unique circadian phenotype, particularly their short FRP, makes them a useful model for examining circadian responses in mice
Agent-based project scheduling
No full textAgent technology offers a new way of thinking about many of the classic problems in operations research. Among these are problems such as project scheduling subject to resource constraints. In this paper, we develop and experimentally evaluate eight agent-based algorithms for solving the multimode, resource-constrained project scheduling problem. Our algorithms differ in the priority rules used to control agent access to resources. We apply our approach to a 51-activity project originally published by Maroto and Tormos [1]. We solve the problem using two types of agent-based systems: (i) a system of simple, reactive agents that we call basic agents; and (ii) a system of more complex, deliberative agents that we call enhanced agents. Of the eight priority rules tested, we find that priority based on shortest processing time performs best in terms of schedule quality when applied by basic agents while the priority based on earliest due date performs best when applied by enhanced agents. In comparing agents across priority rules, we find that enhanced agents generate much better schedules (with makespans up to 66% shorter in some cases) and require only slightly more computation time