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Introduced mammalian predators are responsible for the decline and extinction of many native species, with rats (genus Rattus) being among the most widespread and damaging invaders worldwide. In a naturally fragmented landscape, we demonstrate the multi-year effectiveness of snap traps in the removal of Rattus rattus and Rattus exulans from lava-surrounded forest fragments ranging in size from <0.1 to >10 ha. Relative to other studies, we observed low levels of fragment recolonization. Larger rats were the first to be trapped, with the average size of trapped rats decreasing over time. Rat removal led to distinct shifts in the foraging height and location of mongooses and mice, emphasizing the need to focus control efforts on multiple invasive species at once. Furthermore, because of a specially designed trap casing, we observed low non-target capture rates, suggesting that on Hawai‘i and similar islands lacking native rodents the risk of killing non-target species in snap traps may be lower than the application of rodenticides, which have the potential to contaminate food webs. These efforts demonstrate that targeted snap-trapping is an effective removal method for invasive rats in fragmented habitats and that, where used, monitoring of recolonization should be included as part of a comprehensive biodiversity management strategy.
Healthcare personnel with severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection were interviewed to describe activities and practices in and outside the workplace. Among 2,625 healthcare personnel, workplace-related factors that may increase infection risk were more common among nursing-home personnel than hospital personnel, whereas selected factors outside the workplace were more common among hospital personnel.
A single spray application of a continuously active disinfectant on portable equipment resulted in significant reductions in aerobic colony counts over 7 days and in recovery of Staphylococcus aureus and enterococci: 3 of 93 cultures (3%) versus 11 of 97 (11%) and 20 of 97 (21%) in quaternary ammonium disinfectant and untreated control groups, respectively.
Algorithmic graph theory has been expanding at an extremely rapid rate since the middle of the twentieth century, in parallel with the growth of computer science and the accompanying utilization of computers, where efficient algorithms have been a prime goal. This book presents material on developments on graph algorithms and related concepts that will be of value to both mathematicians and computer scientists, at a level suitable for graduate students, researchers and instructors. The fifteen expository chapters, written by acknowledged international experts on their subjects, focus on the application of algorithms to solve particular problems. All chapters were carefully edited to enhance readability and standardize the chapter structure as well as the terminology and notation. The editors provide basic background material in graph theory, and a chapter written by the book's Academic Consultant, Martin Charles Golumbic (University of Haifa, Israel), provides background material on algorithms as connected with graph theory.
To assess the potential for contamination of personnel, patients, and the environment during use of contaminated N95 respirators and to compare the effectiveness of interventions to reduce contamination.
Simulation study of patient care interactions using N95 respirators contaminated with a higher and lower inocula of the benign virus bacteriophage MS2.
In total, 12 healthcare personnel performed 3 standardized examinations of mannequins including (1) control with suboptimal respirator handling technique, (2) improved technique with glove change after each N95 contact, and (3) control with 1-minute ultraviolet-C light (UV-C) treatment prior to donning. The order of the examinations was randomized within each subject. The frequencies of contamination were compared among groups. Observations and simulations with fluorescent lotion were used to assess routes of transfer leading to contamination.
With suboptimal respirator handling technique, bacteriophage MS2 was frequently transferred to the participants, mannequin, and environmental surfaces and fomites. Improved technique resulted in significantly reduced transfer of MS2 in the higher inoculum simulations (P < .01), whereas UV-C treatment reduced transfer in both the higher- and lower-inoculum simulations (P < .01). Observations and simulations with fluorescent lotion demonstrated multiple potential routes of transfer to participants, mannequin, and surfaces, including both direct contact with the contaminated respirator and indirect contact via contaminated gloves.
Reuse of contaminated N95 respirators can result in contamination of personnel and the environment even when correct technique is used. Decontamination technologies, such as UV-C, could reduce the risk for transmission.
To prioritise and refine a set of evidence-informed statements into advice messages to promote vegetable liking in early childhood, and to determine applicability for dissemination of advice to relevant audiences.
A nominal group technique (NGT) workshop and a Delphi survey were conducted to prioritise and achieve consensus (≥70% agreement) on 30 evidence-informed maternal (perinatal and lactation stage), infant (complementary feeding stage) and early years (family diet stage) vegetable-related advice messages. Messages were validated via triangulation analysis against the strength of evidence from an Umbrella review of strategies to increase children’s vegetable liking, and gaps in advice from a Desktop review of vegetable feeding advice.
A purposeful sample of key stakeholders (NGT workshop, n=8 experts; Delphi survey, n=23 end-users).
Participant consensus identified the most highly ranked priority messages associated with the strategies of: ‘in-utero exposure’ (perinatal and lactation, n=56 points); and ‘vegetable variety’ (complementary feeding, n=97 points; family diet, n=139 points). Triangulation revealed two strategies (‘repeated exposure’ and ‘variety’) and their associated advice messages suitable for policy and practice, 12 for research and four for food industry.
Supported by national and state feeding guideline documents and resources, the advice messages relating to ‘repeated exposure’ and ‘variety’ to increase vegetable liking can be communicated to families and caregivers by healthcare practitioners. The food industry provides a vehicle for advice promotion and product development. Further research, where stronger evidence is needed, could further inform strategies for policy and practice, and food industry application.
The work of Ed Zigler spans decades of research all singularly dedicated to using science to improve the lives of children facing different challenges. The focus of this article is on one of Zigler's numerous lines of work: advocating for the practice of mental age (MA) matching in empirical research, wherein groups of individuals are matched on the basis of developmental level, rather than chronological age. While MA matching practices represented a paradigm shift that provided the seeds from which the developmental approach to developmental disability sprouted, it is not without its own limits. Here, we examine and test the underlying assumption of linearity inherent in MA matching using three commonly used IQ measures. Results provide practical constraints of using MA matching, a solution which we hope refines future clinical and empirical practices, furthering Zigler's legacy of continued commitment to compassionate, meaningful, and rigorous science in the service of children.
Recent estimates of global salt marsh area sit at 5.5 million hectares (Mcowen et al. 2017). Conservatively, this translates to $1 trillion of ecosystem services per annum, potentially as much as $5 trillion (De Groot et al. 2012, Mehvar et al. 2018), equivalent to the entire US federal budget for 2019. There can be little debate as to the value of salt marshes, both in terms of the ecosystem services they provide and the key part they play in helping us understand past climate and sea level trends. This chapter summarizes the preceding work and draws together some key observations and notable knowledge gaps highlighted in the previous chapters. We provide a focus on the expected response of salt marshes to the stresses created by a changing climate.
Salt marshes are considered some of the most biologically diverse and ecologically important regions on Earth, containing thousands of species of robust salt-tolerant plants, crabs, fish, mollusks, zooplankton, algae, and bacteria. Isolated between topographic headlands, laterally continuous behind protective barriers, or associated with extensive delta landscapes, salt marshes are regulated by a variety of physical forces such as waves, tides, rivers, and storm surges, but they are also impacted by climatic variations in temperature and precipitation, riverine flooding, local tectonics, and subsidence (i.e., a deltaic process that describes the lowering of the land surface). Biological forces also play important roles in controlling salt marsh landscapes as many species shape geomorphic development. As these landscapes form and evolve, there exist significant interactions between biology, hydrology, and geology; thus it is impossible to consider salt marsh geomorphology – i.e., how the landscape changes over time – without taking into account these principal interactions.
Having access and skills to use social technology, i.e. social internet use, social media and social applications, are considered as being vital to online social connection. Whilst evidence exists around facilitators and barriers to general technology use, evidence is limited with regards to the motivators, skills and tangible offline benefits older technology users experience with social technology. Therefore, this study used a qualitative, exploratory method to understand older adults’ experiences of using social technology to connect with others. Semi-structured interviews were conducted with 20 older adults (65+ years) across England, Scotland and Wales. Despite having access to social technology for social connection, and using this technology regularly, multiple barriers impacted motivators and skills for use, namely perceived self-efficacy and fear, the culture of online communication, absence of social capital and physical functioning. Some of these barriers of social technology use are reminiscent of barriers of wider technology use and emphasise the importance of addressing these barriers for digital exclusion, as well as social connection. However, some of these barriers were specific to social technology use and should be considered when providing guidance or interventions to increase older adults’ online social connection. Social connection was a clear tangible outcome to social technology use, and individuals discussed the benefits of using social technology, particularly visual communication tools, for online connection.
Vitamin D deficiency is associated with an increased risk of falls and fractures. Assuming this association is causal, we aimed to identify the number and proportion of hospitalisations for falls and hip fractures attributable to vitamin D deficiency (25 hydroxy D (25(OH)D) <50 nmol/l) in Australians aged ≥65 years. We used 25(OH)D data from the 2011/12 Australian Health Survey and relative risks from published meta-analyses to calculate population-attributable fractions for falls and hip fracture. We applied these to data published by the Australian Institute of Health and Welfare to calculate the number of events each year attributable to vitamin D deficiency. In men and women combined, 8·3 % of hospitalisations for falls (7991 events) and almost 8 % of hospitalisations for hip fractures (1315 events) were attributable to vitamin D deficiency. These findings suggest that, even in a sunny country such as Australia, vitamin D deficiency contributes to a considerable number of hospitalisations as a consequence of falls and for treatment of hip fracture in older Australians; in countries where the prevalence of vitamin D deficiency is higher, the impact will be even greater. It is important to mitigate vitamin D deficiency, but whether this should occur through supplementation or increased sun exposure needs consideration of the benefits, harms, practicalities and costs of both approaches.
To investigate the timing and routes of contamination of the rooms of patients newly admitted to the hospital.
Observational cohort study and simulations of pathogen transfer.
A Veterans’ Affairs hospital.
Patients newly admitted to the hospital with no known carriage of healthcare-associated pathogens.
Interactions between the participants and personnel or portable equipment were observed, and cultures of high-touch surfaces, floors, bedding, and patients’ socks and skin were collected for up to 4 days. Cultures were processed for Clostridioides difﬁcile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE). Simulations were conducted with bacteriophage MS2 to assess plausibility of transfer from contaminated floors to high-touch surfaces and to assess the effectiveness of wearing slippers in reducing transfer.
Environmental cultures became positive for at least 1 pathogen in 10 (59%) of the 17 rooms, with cultures positive for MRSA, C. difficile, and VRE in the rooms of 10 (59%), 2 (12%), and 2 (12%) participants, respectively. For all 14 instances of pathogen detection, the initial site of recovery was the floor followed in a subset of patients by detection on sock bottoms, bedding, and high-touch surfaces. In simulations, wearing slippers over hospital socks dramatically reduced transfer of bacteriophage MS2 from the floor to hands and to high-touch surfaces.
Floors may be an underappreciated source of pathogen dissemination in healthcare facilities. Simple interventions such as having patients wear slippers could potentially reduce the risk for transfer of pathogens from floors to hands and high-touch surfaces.
Across the social sciences, scholars regularly pool effects over substantial periods of time, a practice that produces faulty inferences if the underlying data generating process is dynamic. To help researchers better perform principled analyses of time-varying processes, we develop a two-stage procedure based upon techniques for permutation testing and statistical process monitoring. Given time series cross-sectional data, we break the role of time through permutation inference and produce a null distribution that reflects a time-invariant data generating process. The null distribution then serves as a stable reference point, enabling the detection of effect changepoints. In Monte Carlo simulations, our randomization technique outperforms alternatives for changepoint analysis. A particular benefit of our method is that, by establishing the bounds for time-invariant effects before interacting with actual estimates, it is able to differentiate stochastic fluctuations from genuine changes. We demonstrate the method’s utility by applying it to a popular study on the relationship between alliances and the initiation of militarized interstate disputes. The example illustrates how the technique can help researchers make inferences about where changes occur in dynamic relationships and ask important questions about such changes.
There is a growing literature in support of the effectiveness of task-shared mental health interventions in resource-limited settings globally. However, despite evidence that effect sizes are greater in research studies than actual care, the literature is sparse on the impact of such interventions as delivered in routine care. In this paper, we examine the clinical outcomes of routine depression care in a task-shared mental health system established in rural Haiti by the international health care organization Partners In Health, in collaboration with the Haitian Ministry of Health, following the 2010 earthquake.
For patients seeking depression care betw|een January 2016 and December 2019, we conducted mixed-effects longitudinal regression to quantify the effect of depression visit dose on symptoms, incorporating interaction effects to examine the relationship between baseline severity and dose.
306 patients attended 2052 visits. Each visit was associated with an average reduction of 1.11 in depression score (range 0–39), controlling for sex, age, and days in treatment (95% CI −1.478 to −0.91; p < 0.001). Patients with more severe symptoms experienced greater improvement as a function of visits (p = 0.04). Psychotherapy was provided less frequently and medication more often than expected for patients with moderate symptoms.
Our findings support the potential positive impact of scaling up routine mental health services in low- and middle-income countries, despite greater than expected variability in service provision, as well as the importance of understanding potential barriers and facilitators to care as they occur in resource-limited settings.