While the link between non-standard work schedules and poor health outcomes is established, few studies have examined how resources both in and outside of work can support the well-being of workers ...with non-standard work schedules.
Using a cross-sectional survey, we assessed the association between one facet of well-being, life satisfaction, and job and personal resources. In 2019, an electronic survey was administered to two unionized, public service populations who work non-standard work schedules: transportation maintainers and correctional supervisors. We assessed life satisfaction with a 10-item scale; a broad set of job resources (reward satisfaction, supervisor support, co-worker support, schedule satisfaction, and working hours fit); and a broad set of personal resources (health status, sleep, physical activity, and finances). We used log-binomial regression models to estimate prevalence ratios and 95% confidence intervals among statistically significant univariate predictors.
Of the 316 workers surveyed, the majority were male (86%), White (68%), and reported positive life satisfaction (56%). In multivariate models, the prevalence of positive life satisfaction was higher in workers reporting reward satisfaction (PR:1.35, 95% CI: 1.11, 1.65; p = 0.003), good work schedule fit (PR:1.43, 95% CI: 1.12, 1.83; p = 0.004), good health (PR:2.92, 95% CI: 1.70, 4.99; p < 0.0001), and good finances (PR:1.32, 95% CI: 1.01, 1.72; p = 0.04).
Employers should consider increasing work recognition, as well as improving schedule fit, financial well-being, and overall good health in support of worker life satisfaction and ultimately well-being.
Juvenile salmon traveling northwestward to the Pacific Ocean from the Strait of Georgia migrate through and take residence in both Johnstone and Queen Charlotte Straits. Johnstone Strait is a narrow ...and deep passage that is tidally mixed daily, resulting in a nearly isothermal water column, surface to the bottom (approximately 250 m). The trophic gauntlet hypothesis (McKinnell, Curchitser, Groot, Kaeriyama, & Trudel, ) suggests that Johnstone Strait provides a poor growth environment for fish required to transit this area during their migration, due to the oceanographic conditions found there. Using insulin‐like growth factor‐1 (IGF1), a hormone used to assess short‐term growth (within 5–7 days) in fishes, growth was measured in individual juvenile salmon from five species in the Northern Strait of Georgia, Johnstone Strait, Queen Charlotte Strait, and Queen Charlotte Sound in the summer of 2012, 2013, and 2014. All five juvenile salmon species had significantly lower IGF1 concentration in both Johnstone and Queen Charlotte Straits as compared to the Northern Strait of Georgia. These results are consistent with some aspects of the tropic gauntlet hypothesis as growth of juvenile salmon in both Johnstone and Queen Charlotte Straits were significantly lower than found in the Northern Strait of Georgia across all salmon species and all years. In addition, these results demonstrate the utility of growth indices for assessing the effects of environmental variation on juvenile salmon in the presence of a strong ecological driver.
Abstract
Acoustic telemetry is a widely used method in assessing behavioural dynamics in fishes. Telemetry transmitters (tags) are often surgically implanted in the coelom of the animal with limited ...in situ testing and sometimes only assuming that they have minimal rates of post-release tag shedding and mortality. However, fish are capable of expelling tags and mortalities do occur following release, with the mechanism (s) underlying these effects not well-understood. The purpose of this research was to address causal factors underlying tag expulsion and tagging mortality in fishes. We conducted an empirical assessment of tag retention and post-surgical mortality rates in post-smolt Atlantic salmon (
Salmo salar
) fitted with dummy (non-transmitting) acoustic tags over a 92-day monitoring period. This was complimented with a meta-analysis of factors affecting tag retention and post-surgical mortality rates in the wider literature. Post-smolt salmon had high rates of tag expulsion (54.8%), impaired growth, and a foreign body response evident but exhibited low rates of mortality following tag implantation (≤ 5.1%). The meta-analysis showed that mortality was generally low across all studies (12.4%) and was largely unaffected by model cofactors. Tag retention rates were high among the studies investigated here (86.7%) and had a weak negative relationship with tag:body mass ratios. Our results suggest that while mortality is often low among tagging studies, including this one, caution must be exercised in assessing stationary tag location data as they may represent an expelled tag rather than a mortality event. Our results also indicate that tag dimensions are not nearly as important as the tag:body mass ratio.
Radioactive contamination of the Pacific Ocean following the Fukushima nuclear accident has raised public concern about seafood safety, particularly in coastal Indigenous communities. To address ...this, Health Canada and partners have collected and analyzed a total of 621 samples of commonly consumed salmon, ground fish, and shellfish from the Canadian west coast from 2011 to 2018. While the vast majority of the 137Cs and 134Cs levels were below the Minimum Detectable Concentration (MDC, typically 0.7–1.0 Bq kg−1 fw for a 6 h counting), further examination of 19 fish samples revealed 137Cs concentrations of 0.17–0.53 Bq kg−1 fw with an average value and uncertainty (k = 1) of 0.29 ± 0.02 Bq kg−1 fw. Of these, only two samples were found to have trace levels of 134Cs likely derived from the Fukushima accident. The global fallout contribution from atmospheric nuclear weapons testing to the observed 137Cs in these two samples was determined to be 0.26 ± 0.08 Bq kg−1 fw (49 ± 14%) and 0.12 ± 0.02 Bq kg−1 fw (24 ± 4%) for collection years 2015 and 2016, respectively. The annual average level of 137Cs in fish and shellfish was also determined by spectral summation for collection years 2014–2018. In fish, 137Cs levels determined through spectral summation were relatively constant (0.18–0.25 Bq kg−1 fw) with an average value and uncertainty of 0.21 ± 0.02 Bq kg−1 fw. By contrast, 38 shellfish samples (bivalves) were measured and revealed no radiocesium or other anomalies in either tissue or shell. In all, measurements over eight years showed that the radioactivity in fish and shellfish was dominated by natural radionuclides and that the level of anthropogenic radionuclides, as indicated by the radioactive cesium content, remained small. An upper bound for ingested dose from 137Cs was determined to be approximately 0.26 μSv per year, far below the worldwide average annual effective dose of 2400 μSv from exposure to natural background radiation. We can therefore conclude that fish, such as salmon, ground fish, and shellfish from the Canadian west coast are of no radiological health concern despite the Fukushima Dai-ichi nuclear accident of 2011.
•We screened 621 marine samples from Canada's west coast for radioactivity since the Fukushima accident.•Gamma spectral summation employed to derive average 137Cs content of fish and shellfish.•Average activity concentration of 137Cs in fish ranged from 0.18 to 0.25 Bq kg−1 (fresh weight) between 2014 and 2018.•Cesium-134 was identified in two screened fish samples upon further examination.•No observed anthropogenic radioactivity in either shells or meat of shellfish.•Radioactive content dominated by naturally occurring radionuclides and poses no health risk. .
We measured insulin-like growth factor 1 (IGF1) concentrations (a proxy for growth) from juvenile coho Oncorhynchus kisutch, sockeye O. nerka, chum O. keta, and Chinook salmon O. tshawytscha ...collected in 8 regions of British Columbian coastal waters, in June of 2009, 2010, and 2011. We found annual differences in IGF1 for all 4 species, as well as species-specific regional differences in IGF1 concentrations in coho, chum, and sockeye salmon. Sockeye and chum salmon had consistently higher levels in the northern regions of the Dixon Entrance, Haida Gwaii, Hecate Strait, and lower levels in Queen Charlotte Strait. Regional differences in coho, chum, and sockeye salmon were highly correlated (R² = 0.61–0.75). These results demonstrate that salmon growth responds to local environmental variability on a scale of several hundred kilometers. Thus, IGF1 measures should generate insight into fish production on relatively local regional and temporal scales, and these same measures may allow the assessment of how habitats vary on these same scales.
The literature on children born prematurely has consistently shown that full-term babies outperform preterm babies by about 12 IQ points, even when tested as adolescents, and this advantage for ...full-term infants extends to the language and motor domains as well. The results of comprehensive meta-analyses suggest that the degree of prematurity greatly influences later test performance, but these inferences are based on data from an array of separate studies with no control of potential confounding variables such as age. This study analyzed Bayley-4 data for 66 extremely premature infants and toddlers (<32 weeks), 70 moderately premature children (32–36 weeks), and 133 full-term children. All groups were carefully matched on key background variables by the test publisher during the standardization of the Bayley-4. This investigation analyzed data on the five subtests: cognitive, expressive communication, receptive communication, fine motor, and gross motor. A multivariate analysis of covariance (MANCOVA) assessed for group mean differences across the three subsamples, while controlling for the children’s age. Extremely premature children scored significantly lower than moderately premature children on all subtests, and both preterm groups were significantly outscored by the full-term sample across all domains. In each set of comparisons, the cognitive and motor subtests yielded the largest differences, whereas language development, both expressive and receptive, appeared the least impacted by prematurity. A follow-up MANOVA was conducted to examine full-term versus preterm discrepancies on the five subtests for infants (2–17 months) vs. toddlers (18–42 months). For that analysis, the two preterm groups were combined into a single preterm sample, and a significant interaction between the age level and group (full-term vs. preterm) was found. Premature infants scored lower than premature toddlers on receptive communication, fine motor, and cognitive. Neither expressive communication nor gross motor produced significant discrepancies between age groups The findings of this study enrich the preterm literature on the degree of prematurity; the age-based interactions have implications for which abilities are most likely to improve as infants grow into toddlerhood.
Trophic interactions within and among species vary widely across spatial scales and species’ ontogeny. However, the drivers and implications of this variability are not well understood. Juvenile ...Chinook salmon Oncorhynchus tshawytscha have a wide distribution, ranging from northern California to the eastern Bering Sea in North America, but it is largely unknown how their feeding ecology varies and changes with ontogeny across this range. We collected juvenile Chinook salmon and zooplankton using standardized protocols along the coastal Northeast Pacific Ocean. Using a combination of stomach contents and stable isotopes of nitrogen (δ15N) and carbon (δ13C) to characterize feeding ecology, we found regional differences in prey utilization by juvenile Chinook salmon. With growth and ontogeny, juvenile salmon in all regions became equilibrated with oceanic isotopic values. There were regional differences in the δ13C values of juvenile Chinook salmon that may correspond to regional differences in sea surface temperature. There were also regional differences in stable isotope-derived trophic level, and these estimates differed from those derived from stomach contents, possibly due to the different periods over which these metrics integrate. Dietary niche width, as indicated by stable isotopes, corresponded to the expected dietary diversity from stomach contents, combined with the isotopic variability seen in baseline values. Our results indicate strong geographic and ontogenetic differences in feeding ecology of juvenile Chinook salmon. These differences are likely influenced by a combination of ocean-entry date, ocean-entry size, ontogeny, growth rates and regional conditions.
Recruitment variability in many fish populations is postulated to be influenced by climatic and oceanographic variability. However, a mechanistic understanding of the influence of specific variables ...on recruitment is generally lacking. Feeding ecology is one possible mechanism that more directly links ocean conditions and recruitment. We test this mechanism using juvenile Chinook Salmon (Oncorhynchus tshawytscha) collected off the west coast of Vancouver Island, British Columbia, Canada, in 2000–2009. Stable isotopes of carbon (δ13C), an indicator of temperature or primary productivity, and nitrogen (δ15N), an indicator of trophic position, were taken from muscle tissues of genetically stock‐identified salmon. We also collated large‐scale climate indices (e.g., Pacific Decadal Oscillation, North Pacific Gyre Oscillation), local climate variables (e.g., sea surface temperature) and copepod community composition across these years. We used a Bayesian network to determine how ocean conditions influenced feeding ecology, and subsequent survival rates. We found that smolt survival of Chinook Salmon is predicted by their δ13C value, but not their δ15N. In turn, large‐scale climate variability determined the δ13C values of salmon, thus linking climate to survival through feeding ecology, likely through qualities propagated from the base of the food chain.
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