64 research outputs found

    Engaging Long-Term Care Workers in Research: Recruitment Approaches and Participant Characteristics From a Randomized Controlled Trial to Improve COVID-19 Vaccine Confidence.

    Get PDF
    To describe and compare the recruitment methods employed in a randomized controlled trial targeting long-term care workers, and resulting participant baseline characteristics. We used a multifaceted recruitment process to enroll long-term care workers in our 3-arm randomized controlled trial comparing 2 interventions to enhanced usual practice, for improving COVID-19 vaccine confidence and other outcomes. Adult long-term care workers living in the United States employed within the last 2 years were invited to join the study. Participants also had to meet specific screening criteria related to their degree of worry about the vaccine and/or their vaccination status. We used a participatory approach to engage our long-term care stakeholders in codesigning and executing a combination of recruitment methods, including targeted e-recruitment, paid e-recruitment, and in-person recruitment. Participants were screened, consented, and enrolled online. We implemented a participant verification process to ensure the integrity of our study data, and used a tailored participant management platform to manage enrollment. We enrolled 1930 long-term care workers between May 2022 and January 2023. We met our enrollment target, despite each recruitment method having limitations. Total variable costs of approximately 102,700wereincurredanddifferedonaperenrolledparticipantbasisacrossmethods:102,700 were incurred and differed on a per-enrolled participant basis across methods: 25.73 for targeted e-recruitment, 57.12forpaiderecruitment,and57.12 for paid e-recruitment, and 64.92 for in-person methods. Our sample differed from the national population in age, gender, race/ethnicity, education, and role in long-term care. Differences were also observed between online and in-person recruitment methods. Our results support the feasibility of enrolling a large number of long-term care workers in a randomized controlled trial to increase COVID-19 vaccine confidence. Findings build upon the evidence base for engaging this important population in research, a critical step to improving long-term care resident health and well-being. Results from our trial are anticipated in 2024

    Patchiness and Demographic Noise in Three Ecological Examples

    Full text link
    Understanding the causes and effects of spatial aggregation is one of the most fundamental problems in ecology. Aggregation is an emergent phenomenon arising from the interactions between the individuals of the population, able to sense only -at most- local densities of their cohorts. Thus, taking into account the individual-level interactions and fluctuations is essential to reach a correct description of the population. Classic deterministic equations are suitable to describe some aspects of the population, but leave out features related to the stochasticity inherent to the discreteness of the individuals. Stochastic equations for the population do account for these fluctuation-generated effects by means of demographic noise terms but, owing to their complexity, they can be difficult (or, at times, impossible) to deal with. Even when they can be written in a simple form, they are still difficult to numerically integrate due to the presence of the "square-root" intrinsic noise. In this paper, we discuss a simple way to add the effect of demographic stochasticity to three classic, deterministic ecological examples where aggregation plays an important role. We study the resulting equations using a recently-introduced integration scheme especially devised to integrate numerically stochastic equations with demographic noise. Aimed at scrutinizing the ability of these stochastic examples to show aggregation, we find that the three systems not only show patchy configurations, but also undergo a phase transition belonging to the directed percolation universality class.Comment: 20 pages, 5 figures. To appear in J. Stat. Phy

    Systematic review of time lag between antibiotic use and rise of resistant pathogens among hospitalized adults in Europe

    Get PDF
    Background: Antimicrobial resistance (AMR) causes substantial health and economic burden to individuals, healthcare systems and societies globally. Understanding the temporal relationship between antibiotic consumption and antibiotic resistance in hospitalized patients can better inform antibiotic stewardship activities and the time frame for their evaluation. Objectives: This systematic review examined the temporal relationship between antibiotic use and development of antibiotic resistance for 42 pre-defined antibiotic and pathogen combinations in hospitalized adults in Europe. Methods: Searches in MEDLINE, Embase, Cochrane Library and NIHR Centre for Reviews and Dissemination were undertaken from 2000 to August 2021. Pathogens of interest were Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, Staphylococcus aureus, Enterococcus faecium, CoNS, Pseudomonas aeruginosa and Acinetobacter baumannii complex. Results: Twenty-eight ecological studies and one individual-level study were included. Ecological studies were predominantly retrospective in design (19 studies) and of reasonable (20 studies) to high (8 studies) methodological quality. Of the eight pathogens of interest, no relevant data were identified for S. pneumoniae and CoNS. Across all pathogens, the time-lag data from the 28 ecological studies showed a similar pattern, with the majority of studies reporting lags ranging from 0 to 6 months. Conclusions: Development of antibiotic resistance for the investigated antibiotic/pathogen combinations tends to occur over 0 to 6 months following exposure within European hospitals. This information could inform planning of antibiotic stewardship activities in hospital settings

    Ecological Invasion, Roughened Fronts, and a Competitor's Extreme Advance: Integrating Stochastic Spatial-Growth Models

    Full text link
    Both community ecology and conservation biology seek further understanding of factors governing the advance of an invasive species. We model biological invasion as an individual-based, stochastic process on a two-dimensional landscape. An ecologically superior invader and a resident species compete for space preemptively. Our general model includes the basic contact process and a variant of the Eden model as special cases. We employ the concept of a "roughened" front to quantify effects of discreteness and stochasticity on invasion; we emphasize the probability distribution of the front-runner's relative position. That is, we analyze the location of the most advanced invader as the extreme deviation about the front's mean position. We find that a class of models with different assumptions about neighborhood interactions exhibit universal characteristics. That is, key features of the invasion dynamics span a class of models, independently of locally detailed demographic rules. Our results integrate theories of invasive spatial growth and generate novel hypotheses linking habitat or landscape size (length of the invading front) to invasion velocity, and to the relative position of the most advanced invader.Comment: The original publication is available at www.springerlink.com/content/8528v8563r7u2742

    Black Hole Spin via Continuum Fitting and the Role of Spin in Powering Transient Jets

    Full text link
    The spins of ten stellar black holes have been measured using the continuum-fitting method. These black holes are located in two distinct classes of X-ray binary systems, one that is persistently X-ray bright and another that is transient. Both the persistent and transient black holes remain for long periods in a state where their spectra are dominated by a thermal accretion disk component. The spin of a black hole of known mass and distance can be measured by fitting this thermal continuum spectrum to the thin-disk model of Novikov and Thorne; the key fit parameter is the radius of the inner edge of the black hole's accretion disk. Strong observational and theoretical evidence links the inner-disk radius to the radius of the innermost stable circular orbit, which is trivially related to the dimensionless spin parameter a_* of the black hole (|a_*| < 1). The ten spins that have so far been measured by this continuum-fitting method range widely from a_* \approx 0 to a_* > 0.95. The robustness of the method is demonstrated by the dozens or hundreds of independent and consistent measurements of spin that have been obtained for several black holes, and through careful consideration of many sources of systematic error. Among the results discussed is a dichotomy between the transient and persistent black holes; the latter have higher spins and larger masses. Also discussed is recently discovered evidence in the transient sources for a correlation between the power of ballistic jets and black hole spin.Comment: 30 pages. Accepted for publication in Space Science Reviews. Also to appear in hard cover in the Space Sciences Series of ISSI "The Physics of Accretion onto Black Holes" (Springer Publisher). Changes to Sections 5.2, 6.1 and 7.4. Section 7.4 responds to Russell et al. 2013 (MNRAS, 431, 405) who find no evidence for a correlation between the power of ballistic jets and black hole spi

    Can forest management based on natural disturbances maintain ecological resilience?

    Get PDF
    Given the increasingly global stresses on forests, many ecologists argue that managers must maintain ecological resilience: the capacity of ecosystems to absorb disturbances without undergoing fundamental change. In this review we ask: Can the emerging paradigm of natural-disturbance-based management (NDBM) maintain ecological resilience in managed forests? Applying resilience theory requires careful articulation of the ecosystem state under consideration, the disturbances and stresses that affect the persistence of possible alternative states, and the spatial and temporal scales of management relevance. Implementing NDBM while maintaining resilience means recognizing that (i) biodiversity is important for long-term ecosystem persistence, (ii) natural disturbances play a critical role as a generator of structural and compositional heterogeneity at multiple scales, and (iii) traditional management tends to produce forests more homogeneous than those disturbed naturally and increases the likelihood of unexpected catastrophic change by constraining variation of key environmental processes. NDBM may maintain resilience if silvicultural strategies retain the structures and processes that perpetuate desired states while reducing those that enhance resilience of undesirable states. Such strategies require an understanding of harvesting impacts on slow ecosystem processes, such as seed-bank or nutrient dynamics, which in the long term can lead to ecological surprises by altering the forest's capacity to reorganize after disturbance

    On a free boundary problem for a two-species weak competition system

    Get PDF
    [[abstract]]We study a Lotka–Volterra type weak competition model with a free boundary in a one-dimensional habitat. The main objective is to understand the asymptotic behavior of two competing species spreading via a free boundary. We also provide some sufficient conditions for spreading success and spreading failure, respectively. Finally, when spreading successfully, we provide an estimate to show that the spreading speed (if exists) cannot be faster than the minimal speed of traveling wavefront solutions for the competition model on the whole real line without a free boundary.[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子

    NRF2 activation reprogrammes defects in oxidative metabolism to restore macrophage function in COPD

    Get PDF
    Rationale: Chronic obstructive pulmonary disease (COPD) is a disease characterized by persistent airway inflammation and disordered macrophage function. The extent to which alterations in macrophage bioenergetics contribute to impaired antioxidant responses and disease pathogenesis has yet to be fully delineated. Objectives: Through the study of COPD alveolar macrophages (AMs) and peripheral monocyte-derived macrophages (MDMs), we sought to establish if intrinsic defects in core metabolic processes drive macrophage dysfunction and redox imbalance. Methods: AMs and MDMs from donors with COPD and healthy donors underwent functional, metabolic, and transcriptional profiling. Measurements and Main Results: We observed that AMs and MDMs from donors with COPD display a critical depletion in glycolytic- and mitochondrial respiration–derived energy reserves and an overreliance on glycolysis as a source for ATP, resulting in reduced energy status. Defects in oxidative metabolism extend to an impaired redox balance associated with defective expression of the NADPH-generating enzyme, ME1 (malic enzyme 1), a known target of the antioxidant transcription factor NRF2 (nuclear factor erythroid 2–related factor 2). Consequently, selective activation of NRF2 resets the COPD transcriptome, resulting in increased generation of TCA cycle intermediaries, improved energetic status, favorable redox balance, and recovery of macrophage function. Conclusions: In COPD, an inherent loss of metabolic plasticity leads to metabolic exhaustion and reduced redox capacity, which can be rescued by activation of the NRF2 pathway. Targeting these defects, via NRF2 augmentation, may therefore present an attractive therapeutic strategy for the treatment of the aberrant airway inflammation described in COPD

    Diversity of Agaricales (Basidiomycota) in the Reserva Biológica Walter Egler, Amazonas, Brazil

    Get PDF
    A study of the order Agaricales Clements (Hymenomycetes, Basidiomycotina), occurring in the Reserva Biológica Walter Egler was carried out from December 2000 to June 2001. The area of study is situated at Road AM-010, Manaus-Itacoatiara, km 64, Latitude 02° 43' S and Longitude 59° 47' W, Rio Preto da Eva, in the State of Amazonas, with a total area of 709 ha of terra firme rain forest. The fungi collected were identified based on traditional methodology for identification of Agaricales. A total of 39 species were studied, distributed in 13 genera and six families: Polyporaceae: Pleurotus sp.; Hygrophoraceae: Hygrocybe cf. megistospora, Hygrocybe aff. miniceps, Hygrocybe occidentalis var. scarletina and eight indeterminate species of Hygrocybe; Tricholomataceae: Clitocybe sp., Hydropus sp.1 and Hydropus sp.2, Macrocystidia sp., Marasmiellus sp., Marasmius bellus, Marasmius haedinus var. haedinus, Marasmius cf. leoninus, Marasmius cf. mazatecus, Marasmius cf. ruber, Marasmius cf. setulosifolius, Marasmius tageticolor, Marasmius cf. variabiliceps var. variabiliceps, Marasmius sp.1, Marasmius sp.2, Marasmius sp.3 and Marasmius sp.4, Tricholoma sp.; Agaricaceae: Agaricus sp.1 and Agaricus sp.2, Lepiota sp., Cystoderma sp.; Entolomataceae: Entoloma cf. azureoviride, Entoloma cf. cystidiophorum, Entoloma strigosissima, Entoloma sp.; Russulaceae: Lactarius panuoides. Entoloma azureoviride, Hygrocybe miniceps, Lactarius panuoides, Marasmius cf. mazatecus, Marasmius cf. setulosifolius and Marasmius variabiliceps var. variabiliceps, apparently are here cited for the first time from Brazil. With exception of Marasmius tageticolor, all species are cited here for the first time as occurring in Egler Forest. The tables with the species occurrence, in accordance with the topographical gradient (sand bank, incline, plateau) and its respective habitat, are supplied.", 'enFoi realizado um estudo dos representantes da Ordem Agaricales Clements (Hymenomycetes, Basidiomycotina), ocorrentes na Reserva Biológica Walter Egler, situada na Estrada AM-010, Manaus-Itacoatiara, Km 64, Latitude 02° 43' S e Longitude 59° 47' W, Rio Preto da Eva, Amazonas. A área abrange 709 ha de floresta de terra firme primária. As coletas foram realizadas no período de dezembro de 2000 a junho de 2001 e seguiu-se a metodologia usual para identificação de Agaricales. Foram estudadas um total de 39 espécies, distribuídas em 13 gêneros e seis famíliasPolyporaceaePleurotus sp.; HygrophoraceaeHygrocybe cf. megistospora, Hygrocybe aff. miniceps, Hygrocybe occidentalis var. scarletina, e mais oito espécies de Hygrocybe indeterminadas; TricholomataceaeClitocybe sp., Hydropus sp.1 e Hydropus sp.2, Macrocystidia sp., Marasmiellus sp., Marasmius bellus, Marasmius haedinus var. haedinus,Marasmius cf. leoninus, Marasmius cf. mazatecus, Marasmius cf. ruber,Marasmius cf. setulosifolius, Marasmius tageticolor, Marasmius cf. variabiliceps var. variabiliceps, Marasmius sp.1, Marasmius sp.2, Marasmius sp.3 e Marasmius sp.4, Tricholoma sp.; AgaricaceaeAgaricus sp.1 e Agaricus sp.2, Lepiota sp., Cystoderma sp.; EntolomataceaeEntoloma cf. azureoviride, Entoloma cf. cystidiophorum, Entoloma strigosissima, Entoloma sp.; RussulaceaeLactarius panuoides. Destas, Entoloma azureoviride, Hygrocybe miniceps, Lactarius panuoides, Marasmius cf. mazatecus, Marasmius cf. setulosifolius e Marasmius variabiliceps var. variabiliceps, provavelmente, estão sendo aqui citadas pela primeira vez, para o Brasil. Com exceção de Marasmius tageticolor, as demais espécies são citadas pela primeira vez, para a Reserva Egler. São fornecidas tabelas com a ocorrência das espécies de acordo com o gradiente topográfico (baixio, vertente, platô) e seus respectivos habitats
    corecore