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Changes in ecosystems after the removal of stress provide a rich source of information for conservation science. We used a long-term regional data set on the performance of white sucker (Catostomus commersonii) collected before and after the closure of a pulp mill to explore recovery in fish. Physiological indicators, including liver enzymes and plasma steroids, showed some compelling changes after the closure of the mill consistent with reduced exposure to pulp mill effluent but did not unequivocally demonstrate recovery. However, persistent signals in these fish may indicate effects of impoundment or discharge of sewage. We also used quantile regression with environmental covariates and bootstrap iteration to determine if systematic variation remained in relative body weight, liver weight, and gonad weight. In fish formerly exposed to pulp mill effluent, we found evidence of improvements (male gonad weight and liver weight of males and females), degradation (gonad weight of females), and no change (body weight). Although the observed patterns may be associated with closure of the mill, some differences were also found at regional locations, suggesting roles of additional stressors and challenging the clear association of change at the Mattagami River exposure site with the closure of the mill. However, fish captured at this location show responses consistent with regional locations, suggesting no residual impacts and highlights the challenges of identifying changes in fish even after large and known interventions. Environ Toxicol Chem 2021;40:162-176. © 2020 SETAC., (© 2020 SETAC.)

A bleached kraft pulp mill discharging effluent to the Mattagami River in northern Ontario, Canada, closed after almost 90 yr of operation. During its operation, effluent from the mill influenced biota in the downstream areas. To assess shifts in the reliance of biota from mill-derived nutrients, the isotopic composition (δ 13 C and δ 15 N) of white sucker (Catostomus commersoni) muscle and whole mayflies (Hexagenia sp.) were compared before (1990s) and after the pulp mill's closure (2012-2014). To better understand other potential sources of spatial and temporal change, samples from 3 other tributaries in the basin with dams, ongoing pulp mill operations, sites receiving sewage, and at several reference sites were collected and compared. Irrespective of time period, biota collected at sites downstream of both dams and active pulp mills tended to have elevated δ 13 C values, but variable changes in δ 15 N (negligible in most cases) when compared with upstream samples. The isotopic composition of mayflies varied at reference sites over time, with decreasing values of δ 13 C and δ 15 N (mayflies only) with increasing depth, and there was evidence of lower δ 13 C in fish after the pulp mill closure. Overall, these results suggest the importance of long-term, regional-scale measurements for documenting the effects of stressors on nutrient use by aquatic species. Environ Toxicol Chem 2020;39:1207-1218. © 2020 SETAC., (© 2020 SETAC.)

Objective: The purpose of this study was to investigate the effects of hybrid environments (i.e. where part of the patient record is paper-based and part of it is electronic) upon aspects of novice nurse information seeking (i.e. amount of information accessed, choice of key information sources, type of information and use of information seeking tactics)., Methods: A within group, laboratory, experimental study was conducted using two simulated environments (i.e. a paper environment and a hybrid environment). Thirty-five novice nurses participated in the study., Results: Findings revealed significant differences between the paper and hybrid environments in terms of their effects upon aspects of novice nurse information seeking. Subjects accessed: 1) less information in the hybrid environment than the paper environment, 2) more non-electronic sources of information were accessed by novice nurses in the hybrid environment, and 3) novice nurses used more passive information seeking tactics in the hybrid environment than the paper environment. Qualitative findings from the cued recall data revealed subjects experienced increased cognitive load in the hybrid environment., Conclusions: Hybrid environments may affect aspects of novice nurse information seeking. Future research should explore the effects of hybrid environments upon the information seeking of other types of health professionals (e.g. physicians, physiotherapists) with differing levels of expertise (i.e. novice, intermediate and expert).

This qualitative study explored characteristics of a record-keeping log that students would find appealing and be receptive to using. A heterogeneous sample of undergraduate university students aged 18 to 25 years participated. An experienced moderator, using a semistructured interview guide, conducted 13 focus groups (N = 65). All focus groups were audio-recorded and transcribed verbatim. Inductive content analysis was conducted independently by two qualitative researchers. Measures were incorporated throughout the study to ensure data trustworthiness. Four themes illustrated students' suggestions for the log: layout, convenience, maximum distribution, and concerns. In particular, students discussed the use of a computer-based versus a paper-based log, hesitancies in using a log, and the need for: additional health information, multivenue distribution, and low to no cost. Students confirmed that a record-keeping log tailored to their needs and preferences would be attractive and appealing to students.

In the early 1990s, many Canadian pulp and paper mills implemented process changes to comply with new regulations that came into effect in 1993. These regulations placed stricter guidelines on a number of parameters in effluent discharges, including limits on acute toxicity, on the discharges of suspended solids, and on biochemical oxygen demand. To meet these new regulations, many of the older Canadian pulp and paper mills had to install secondary treatment systems. The investment by the Canadian pulp and paper industry was in excess of $5 billion, and the implementation of the new regulations and the process changes took several years. The new regulations were an extension of regulations designed in the early 1970s and were not designed specifically to address the reproductive responses recently reported in fish collected downstream of mills in Scandinavia and North America. This report describes a series of projects conducted between 1991 and 1996 to evaluate the effectiveness of the new regulations to address the issue of reproductive responses in fish associated with exposure to pulp-mill effluents. These studies have shown that the existing short-term bioassays do not adequately predict the potential of effluents to affect reproduction in wild fish. Laboratory testing using fathead minnows exposed over a full life cycle confirmed depression in sex steroid production, delay in sexual maturity, reduced egg production, and changes in secondary sex characteristics documented at some sites. Our studies demonstrated that both steroid hormone changes and induction of liver detoxification enzymes take place quickly. While short-term exposures can predict the potential of some effluents to impact steroid hormone production, there is no readily available assay that can be widely applied. In the absence of a usable and transferable laboratory bioassay, field collections were conducted at a number of sites. Generalizations are not possible at this time, but impacts have been seen at a variety of sites, and partial recovery has been documented at five sites in North America following various process and waste treatment changes. Data gaps and critical research areas are identified.

Exposure of feral fish populations to bleached kraft pulp mill effluent (BKME) results in a variety of negative impacts on reproductive fitness including reduced ovarian development, reduced egg size, decreased fecundity with age, delayed sexual maturation, and alterations in reproductive endocrine homeostasis at multiple sites along the pituitary-gonadal axis. The present study provides evidence of elevated apoptotic DNA fragmentation and increased expression of the 70-kDa heat shock protein (HSP70) in ovarian follicular cells from prespawning white sucker (Catostomus commersoni) exposed to BKME. Apoptosis is the molecular mechanism responsible for ovarian follicular atresia which is involved in various stages of vertebrate ovarian development such as follicular recruitment, growth, differentiation, and regression. In mammals, induction of HSP70 is associated with inhibition of hormone-sensitive steroidogenesis and mediation of luteal regression. The 3'-end labeling of isolated ovarian follicular cell DNA revealed a 10-fold increase in the extent of apoptosis in BKME-exposed white sucker in comparison to follicles collected from a nearby reference site. Western blotting for ovarian follicular HSP70 levels showed increased expression of this protein in fish exposed to BKME. The elevated ovarian cell apoptosis and increased HSP70 expression in BKME-exposed fish were associated with reduced ovary size, decreased plasma testosterone, and increased plasma 17 beta-estradiol concentrations, but not induction of hepatic ethoxyresorufin O-deethylase activity. It is not known whether increased ovarian HSP70 expression in BKME-exposed fish is related to elevated apoptosis or represents a general response to environmental stress. Since apoptosis is regulated by several hormonal factors and conserved gene products, these data suggest that certain components of BKME increase ovarian cell apoptosis in fish via stimulation of cell death signaling. However, it is unclear whether BKME stimulates ovarian cell apoptosis directly or if this response occurs secondarily as a result of altered reproductive endocrine homeostasis.

Objective: To describe the authors' first year's experience with a picture archiving and communication system (PACS) for the management and storage of ultrasound images and to discuss the financial impact of the system in terms of costs of purchase, installation and operation., Materials and Methods: The Toronto Hospital, General Division, performs more than 30000 ultrasound studies each year. On June 27, 1994, an Ultra PACS (ALI Technology Incorporated, Richmond, BC) was introduced as the only method of image storage and archiving in the Ultrasound Division., Results: After structural renovations and a detailed work flow analysis, the Ultrasound Division converted from film to the PACS over a single weekend with no back-up. The advantages to date include consistently high-quality images; rapid image retrieval (images from the same day [online], 0 to 45 seconds; archived images [online], 3 to 5 minutes; images in storage [offline], 3 minutes); no loss of images; more efficient patient through-put, which allows the division to handle the same number of patients in 20% less operational time (change from a 10-hour day to an 8-hour day, over a 5-day week); less end-of-day overtime; and an improved work environment. There has been no change in the division's complement of full-time equivalent technologists, the number of film librarians has been reduced by 1, and physician service time has decreased by 20%. There has been no significant impact on overall operational financial status., Conclusion: The PACS has proved an efficient method for managing large numbers of ultrasound images in a cost-effective and technically sound manner. Its installation provides the basis for meeting the Ultrasound Division's next objective, to eliminate paper as the primary method of managing patient information and reports.