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Do rats run and respond at a higher rate to run during the dark phase when they are typically more active? To answer this question, Long Evans rats were exposed to a response-initiated variable interval 30-s schedule of wheel-running reinforcement during light and dark cycles. Wheel-running and local lever-pressing rates increased modestly during the dark phase. A second experiment examined the potential role of food-anticipatory activity in this effect by delaying postexperimental session feeding by 6 hr. No increase in wheel-running and lever-pressing rates was observed during the dark phase. This suggests that the effect of light/dark cycle on running and responding for the opportunity to run depended upon food-anticipatory activity. (Contains 2 figures and 1 table.)

This paper was inspired by the incomplete story of Englishwoman Isabel 'Jack' May (1875–1970), a media sensation from 1905 to 1912 because she was a 'lady farmer', wore 'male attire' and adopted the name 'Jack'. Already well-known in England, May's celebrity was enhanced when she purchased land in Alberta, Canada in 1911, where she farmed with a female companion. In late 1912 however, May sailed to England, never to return, and disappeared from public view. In Sarah Carter's 2016 book Imperial Plots, May's fate was a mystery, but Carter surmised May did not feel welcome in the Canadian West where gender transgressors were shunned. The authors, inspired by Laite's 'small history in a digital age' methodological approach, discovered a deeper, richer and more complex life history. This paper reconstructs May's life and analyses the intense media scrutiny which positioned her as an aberration against traditional femininity to understand more about the lives of other non-conforming women of this period. While we argue that May was not transgender, rather living openly as a cross-dressing woman, her self-identification as 'farmer' and decision to spend her adult life with same-sex companions, offers an alternative view of trans and queer 'spaces of possibility'. [ABSTRACT FROM AUTHOR]

Investigated relationship between School Problem Screening Inventory, Fifth Edition (SPSI) and Bristol Social Adjustment Guides (BSAG) and Wechsler Intelligence Scale for Children-Revised. Findings from 43 junior high school students with behavior problems showed SPSI Behavior Disorder undercontrolled and overcontrolled scores to be moderately correlated with BSAG Overreaction and Underreaction scores, respectively. (Author/NB)

An approximate 1:1 sex ratio of American lobsters can be skewed due to environmental factors or fisheries management. Substantial skewness can impact mating behaviour and lower reproduction which could have far-reaching ecological and economic consequences. The aim was to investigate the sex ratio patterns of lobsters in two lobster fishing areas (LFAs) in southwestern Nova Scotia, Canada and identify factors associated with skewed sex ratios. This study analyzed biological data from more than 270,000 lobsters sampled over ten years (2010–2019) by the Fishermen and Scientists Research Society. A mixed effect logistic regression model evaluated the effect of spatial, temporal and environmental factors as well as size on the sex ratio of lobsters. There were significant temporal patterns in sex ratios that differed by LFA. After the effects of sampling month, year and LFA were accounted for, lower bottom temperature and deeper water depth were associated with a higher prevalence of females, especially in larger lobsters. We present the first long term analyses of sex ratio patterns in H. americanus in Atlantic Canada's most commercially important region for this species and provide evidence that these patterns are influenced by environmental factors and fisheries. In view of future climate change scenarios, monitoring the population dynamics of this iconic fishery species is crucial to ensure sustainable fisheries and healthy lobster stocks. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Pathology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study examines the gender differences in Chinese-Canadian family caregivers providing care to elderly Chinese care receivers. A random sample of 339 Chinese-Canadian caregivers for elderly care receivers completed a telephone survey. Most of the Chinese family caregivers were females. No major gender differences were reported in the amount and types of caregiving tasks. The level of caregiving burden and predictors were generally similar for both gender groups. Contrary to common belief that sons and daughters-in-law are the key family caregivers in the Chinese culture, the daughters played a more important role in family caregiving. In addition to providing support and services to Chinese female caregivers, strategies to enhance Chinese males' involvement in family caregiving are needed and discussed in the paper. [ABSTRACT FROM AUTHOR]

The relative virulence of 109 Ascochyta isolates collected from pea fields in Alberta from 1996 to 1998 were evaluated on 10-day-old seedlings by the excised leaf-assay technique. Twenty-eight isolates were avirulent, while the others produced lesions of various sizes on pea leaves. DNA samples from 86 isolates were amplified by the RAPD technique using PCR with single primers. One dominant genotype of Ascochyta pisi was identified throughout Alberta, but variations in virulence were not clearly differentiated by the RAPD technique. Five Ascochyta isolates, four virulent and one avirulent, were used to assess the susceptibility of 20 field pea cultivars available in Alberta, including 13 yellow types and seven green types. Based on symptom development, the yellow-type cultivars Swing, Eiffel and Delta, and the green-type cultivar Orb, were the most susceptible. Of yellow-type cultivars, Voyageur, Carneval and Montana were most resistant to Ascochyta infection. [ABSTRACT FROM AUTHOR]

Sclerotium rolfsii was isolated from diseased rhizomes of greenhouse-grown Alstroemeria (Alstroemeria sp.) in Edmonton in 1992. The underground portions of the plants were attacked resulting in leaf chlorosis which started on the lower leaves and gradually moved upwards. The characteristics of the isolates from diseased Alstroemeria were compared with those from other crops. This is the first report of S. rolfsii on Alstroemeria in Canada. [ABSTRACT FROM AUTHOR]

Abstract The North American mid-continent population of lesser snow geese (Anser caerulescens caerulescens) breeds in coastal areas of the Hudson Bay region. Breeding success is highly variable, particularly during recent decades. The availability of long-term data sets of weather and the breeding success of geese allowed us to determine whether climatic variables in spring and early summer (May–June) are reliable predictors of different attributes of the reproductive biology of snow geese. A large region of strong anomalous cooling in north-eastern North America has been the dominant anomalous climatic feature since the mid-1970s. The cooling which becomes established during winter persists into spring and early summer when migration, nesting and hatching of geese are occurring. Redundancy analysis (RDA) of the data sets was made to identify dominant correlations and regression relationships between climatic and goose variables. Individual goose response variables were further explored with stepwise multiple regression and bipartial regression. 96.7% of year-to-year variance in the goose data was explained by the selected climatic data. The first four orthogonal axes out of seven possible axes explained 92.2% of the total variance. Date of last snow on the ground and mean daily temperature from 6 to 20 May formed the lowest and highest predictor scores, respectively. Initiation date and hatching date at the low end and total clutch size and clutch size at hatch at the high end were associated with these extremes, particularly in certain years. Days of freezing rain in May and total rainfall were correlated with nest failure. Bivariate correlation/regression showed that the most parsimonious model for nest initiation day was based on four climatic predictors, for hatching day four predictors, and for clutch size at hatch, nine predictors. Both the multiple regression analyses and the redundancy analyses confirm the high degree of predictability of goose... [ABSTRACT FROM AUTHOR]

The article discusses the foundation of the Canadian Meteorological and Oceanographic Society in Canada. The institution is open to those who have the interest in meteorology and/or oceanography and the name Atmosphere, the principal publication of the Society, was expanded into a new title Atmosphere-Ocean. The changes made on the society was unanimously approved by the members in congress. The merger of scientific interest was done by members of the executive and by members of the Oceanographic Division in 1975 to discuss the responsibilities, purpose and future of the organization.