The quality of lake ice is of uppermost importance for ice safety and under-ice ecology, but its temporal and spatial variability is largely unknown. Here we conducted a coordinated lake ice quality ...sampling campaign across the Northern Hemisphere during one of the warmest winters since 1880 and show that lake ice during 2020/2021 commonly consisted of unstable white ice, at times contributing up to 100% to the total ice thickness. We observed that white ice increased over the winter season, becoming thickest and constituting the largest proportion of the ice layer towards the end of the ice cover season when fatal winter drownings occur most often and light limits the growth and reproduction of primary producers. We attribute the dominance of white ice before ice-off to air temperatures varying around the freezing point, a condition which occurs more frequently during warmer winters. Thus, under continued global warming, the prevalence of white ice is likely to substantially increase during the critical period before ice-off, for which we adjusted commonly used equations for human ice safety and light transmittance through ice.
Aim: Decision-making for conservation management often involves evaluating risks in the face of environmental uncertainty. Models support decision-making by (1) synthesizing available knowledge in a ...systematic, rational and transparent way and (2) providing a platform for exploring and resolving uncertainty about the consequences of management decisions. Despite their benefits, models are still not used in many conservation decision-making contexts. In this article, we provide evidence of common objections to the use of models in environmental decision-making. In response, we present a series of practical solutions for modellers to help improve the effectiveness and relevance of their work in conservation decision-making. Location: Global review. Methods: We reviewed scientific and grey literature for evidence of common objections to the use of models in conservation decision-making. We present a set of practical solutions based on theory, empirical evidence and best-practice examples to help modellers substantively address these objections. Results: We recommend using a structured decision-making framework to guide good modelling practice in decision-making and highlight a variety of modelling techniques that can be used to support the process. We emphasize the importance of participatory decision-making to improve the knowledge-base and social acceptance of decisions and to facilitate better conservation outcomes. Improving communication and building trust are key to successfully engaging participants, and we suggest some practical solutions to help modellers develop these skills. Main conclusions: If implemented, we believe these practical solutions could help broaden the use of models, forging deeper and more appropriate linkages between science and management for the improvement of conservation decision-making.
Poor marital satisfaction is associated with high-risk sexual behavior and HIV transmission. We tested whether a counselor-led couple education and counseling intervention dubbed Waya (paternal aunt) ...would improve marital satisfaction and reduce HIV risk behavior among married couples in Kisumu County, western Kenya. In a pre–post design, we enrolled 60 heterosexual married couples at high risk for HIV to undergo five 1-h couple education and counseling sessions over 56 days. We collected self-reported data on marital satisfaction, the number of sex partners, and condom use with extramarital partners at pre- and post-intervention visits. We used Wilcoxon and McNemar tests to examine the association of our intervention with marital relationship satisfaction and reduction in HIV risk sexual behavior. The intervention was associated with marital relationship satisfaction score improvement from a median of 5 (interquartile range IQR, 4–5) to 6 (IQR, 6–7) among men and 4 (IQR, 3–5) to 6 (IQR, 5–6) among women (
p
< .01). The intervention was also associated with reducing HIV risk sexual behaviors depicted by a reduction in the number of sex partners in the past one month and an increase in consistent extramarital condom use. The number of sex partners reduced from a median of 2 (IQR, 1–2) to 1 (IQR, 1–2) and consistent extramarital condom use increased from 4% at baseline to 56% among men. Our intervention was associated with improvements in marital relationship satisfaction and reductions in HIV high-risk behaviors necessary for achieving epidemic control in HIV hotspots such as fishing communities in western Kenya.
Most risk assessments assume uncertainty may be decomposed into variability and incertitude. Language is often overlooked as a source of uncertainty, but linguistic uncertainty may be pervasive in ...workshops, committees, and other face‐to‐face language‐based settings where it can result in misunderstanding and arbitrary disagreement. Here we present examples of linguistic uncertainty drawn from qualitative risk analysis undertaken in stakeholder workshops and describe how the uncertainties were treated. We used a process of iterative re‐assessment of likelihoods and consequences, interspersed with facilitated discussion, to assist in the reduction of language‐based uncertainty. The effects of this process were evident as changes in the level of agreement among groups of assessors in the ranking of hazards.
The skeleton is frequently affected in individuals with neurofibromatosis type 1, and some of these bone manifestations can result in significant morbidity. The natural history and pathogenesis of ...the skeletal abnormalities of this disorder are poorly understood and consequently therapeutic options for these manifestations are currently limited. The Children's Tumor Foundation convened an International Neurofibromatosis Type 1 Bone Abnormalities Consortium to address future directions for clinical trials in skeletal abnormalities associated with this disorder. This report reviews the clinical skeletal manifestations and available preclinical mouse models and summarizes key issues that present barriers to optimal clinical management of skeletal abnormalities in neurofibromatosis type 1. These concepts should help advance optimal clinical management of the skeletal abnormalities in this disease and address major difficulties encountered for the design of clinical trials.
Pseudomonas aeruginosa is an important cause of nosocomial infections and is frequently present in the airways of cystic fibrosis patients. Quorum sensing mediates P. aeruginosa's virulence and ...biofilm formation through density-dependent interbacterial signaling with autoinducers. N-3-oxododecanoyl homoserine lactone (3OC12-HSL) is the major autoinducer in P. aeruginosa. We have previously shown that human airway epithelia and paraoxonases (PONs) degrade 3OC12-HSL. This study investigated the role of PON1, PON2, and PON3 in airway epithelial cell inactivation of 3OC12-HSL. All three PONs were present in murine tracheal epithelial cells, with PON2 and PON3 expressed at the highest levels. Lysates of tracheal epithelial cells from PON2, but not PON1 or PON3, knockout mice had impaired 3OC12-HSL inactivation compared with wild-type mice. In contrast, PON1-, PON2-, or PON3-targeted deletions did not affect 3OC12-HSL degradation by intact epithelia. Overexpression of PON2 enhanced 3OC12-HSL degradation by human airway epithelial cell lysates but not by intact epithelia. Finally, using a quorum-sensing reporter strain of P. aeruginosa, we found that quorum sensing was enhanced in PON2-deficient airway epithelia. In summary, these results show that loss of PON2 impairs 3OC12-HSL degradation by airway epithelial cells and suggests that diffusion of 3OC12-HSL into the airway cells can be the rate-limiting step for degradation of the molecule.
We sought to determine the outcomes of initiating long-term dialysis of neonates and children aged > 1 to 24 months with end-stage renal disease.
By querying the North American Pediatric Renal Trials ...and Collaborative Studies database, we obtained information on 193 neonates (< or = 1 month of age) and 505 children (> 1-24 months of age) with a presumptive diagnosis of end-stage renal disease who initiated long-term dialysis. Dialysis characteristics and likelihood of hospitalization were compared using the chi2 test, and duration of hospitalization was compared using the Wilcoxon 2-sample test. Product limit methods were implemented, and the log rank test was used to compare time-to-event analyses. Multivariate analyses were performed using Cox proportional hazards models.
Neonates with end-stage renal disease were more likely to receive peritoneal dialysis versus hemodialysis than older children with end-stage renal disease. Moreover, neonates who initiated dialysis during the first month of life were just as likely to terminate dialysis as were the older children. Rates of renal transplantation were significantly lower in the neonates compared with the older children, but neonates were more likely to recover function of the native kidney. Although neonates were more often hospitalized, their overall risk of mortality was similar to that observed in older children.
Neonates with a presumptive diagnosis of end-stage renal disease may initiate long-term dialysis during the first month of life with outcomes comparable to those of patients who initiate dialysis later in infancy.
The role played by bacteria during the pioneering stages of colonisation on marine coatings was investigated over three distinct seasons in both tropical and temperate environments. Novel methods ...were developed to facilitate the study of the adhered bacterial population on the test coatings in their native, hydrated state. The approach eliminated destructive sample preparation techniques, including sample dehydration and/or removal from the substratum surface prior to analysis. Bacterial colonisation during initial biofilm formation was evaluated on two antifouling paints, Intersmooth 360® and Super Yacht 800®, and a fouling release coating, Intersleek 700®. Bacterial colonisation was quantified on all three coating surfaces. Intersleek 700 displayed the quickest colonisation by bacteria, resulting in major modification of the substratum surface within 2-4 days following immersion in the ocean. Whilst fouling accumulated more quickly on Intersleek 700, by 16 days all three coatings were fouled significantly. Bacterial fouling was correlated to both location and season, with fouling occurring at a more rapid rate at the Cairns location, as well as during the summer months, when higher water temperatures were recorded. Successful colonisation of all coatings by bacteria soon after immersion modifies the characteristics of the surfaces at the hull/water interface, and subsequent settlement by higher biofouling organisms must be moderated by these modified surfaces.
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