3,297 research outputs found

    Basin bifurcations, oscillatory instability and rate-induced thresholds for AMOC in a global oceanic box model

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    The Atlantic Meridional Overturning Circulation (AMOC) transports substantial amounts of heat into the North Atlantic sector, and hence is of very high importance in regional climate projections. The AMOC has been observed to show multi-stability across a range of models of different complexity. The simplest models find a bifurcation associated with the AMOC `on' state losing stability that is a saddle node. Here we study a physically derived global oceanic model of Wood {\em et al} with five boxes, that is calibrated to runs of the FAMOUS coupled atmosphere-ocean general circulation model. We find the loss of stability of the `on' state is due to a subcritical Hopf for parameters from both pre-industrial and doubled CO2{}_2 atmospheres. This loss of stability via subcritical Hopf bifurcation has important consequences for the behaviour of the basin of attraction close to bifurcation. We consider various time-dependent profiles of freshwater forcing to the system, and find that rate-induced thresholds for tipping can appear, even for perturbations that do not cross the bifurcation. Understanding how such state transitions occur is important in determining allowable safe climate change mitigation pathways to avoid collapse of the AMOC.Comment: 18 figure

    Spatial and temporal dynamics and value of nature-based recreation, estimated via social media

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    Conserved lands provide multiple ecosystem services, including opportunities for naturebased recreation. Managing this service requires understanding the landscape attributes underpinning its provision, and how changes in land management affect its contribution to human wellbeing over time. However, evidence from both spatially explicit and temporally dynamic analyses is scarce, often due to data limitations. In this study, we investigated nature-based recreation within conserved lands in Vermont, USA.We used geotagged photographs uploaded to the photo-sharingwebsite Flickr to quantify visits by in-state and outof- state visitors, and we multiplied visits by mean trip expenditures to show that conserved lands contributed US 1.8billion(US1.8 billion (US 0.18\u2720.2 at 95% confidence) to Vermont\u27s tourism industry between 2007 and 2014.We found eight landscape attributes explained the pattern of visits to conserved lands; visits were higher in larger conserved lands, with less forest cover, greater trail density and more opportunities for snow sports. Some of these attributes differed from those found in other locations, but all aligned with our understanding of recreation in Vermont.We also found that using temporally static models to informconservation decisions may have perverse outcomes for nature-based recreation. For example, static models suggest conserved land with less forest cover receive more visits, but temporally dynamic models suggest clearing forests decreases, rather than increases, visits to these sites. Our results illustrate the importance of understanding both the spatial and temporal dynamics of ecosystem services for conservation decision-making

    Incubation and Grazing Effects on Spirotrich Ciliate Diversity Inferred from Molecular Analyses of Microcosm Experiments

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    We used an experimental approach of analyzing marine microcosms to evaluate the impact of both predation (top-down) and food resources (bottom-up) on spirotrich ciliate communities. To assess the diversity, we used two molecular methods-denaturing gradient gel electrophoresis (DGGE) and high-throughput sequencing (HTS). We carried out two types of experiments to measure top-down (adult copepods as predators) and bottom-up effects (phytoplankton as food resources) on the spirotrich ciliates. We observed both strong incubation effects (untreated controls departed from initial assessment of diversity) and high variability across replicates within treatments, particularly for the bottom-up experiments. This suggests a rapid community turn-over during incubation and differential susceptibility to the effects of experimental manipulation. Despite the variability, our analyses reveal some broad patterns such as (1) increasing adult copepod predator abundance had a greater impact on spirotrich ciliates than on other microbial eukaryotes; (2) there was no evidence for strong food selection by the dominant spirotrich ciliates

    Rebuilding a foundation of trust: A call to action in creating a safe environment for everyone

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    Well before the COVID-19 pandemic, incivility and physical threats directed toward healthcare employees and often registered nurses was a growing concern by Chief Nurse Executive (CNE) leaders. In 2019, conversations initiated by The Beryl Institute’s Nurse Executive Council (NEC) to consider how best to achieve a much-needed balance between patient/family and staff safety have now become a critical priority to ensure the safety of everyone receiving and providing health care services. The heart of this work was organized around a set of newly developed ethical precepts designed to guide the exploration of key concepts. A call to action grounded in rebuilding a foundation of trust is proposed. In pursuing future steps to deepen this foundation, and to reaffirm the vital role for nurse leaders and of all in healthcare, we must be willing to engage in dialogue, to ask openly, and question respectfully. We believe healthcare systems and nurse leaders both play a vital role in elevating the humanity on which we will find brighter days ahead. Through a sustained commitment to this aim, we seek to strengthen health care delivery environments that shape physically and psychologically safe environments for everyone. Experience Framework This article is associated with the Culture & Leadership lens of The Beryl Institute Experience Framework (https://www.theberylinstitute.org/ExperienceFramework). Access other PXJ articles related to this lens. Access other resources related to this len

    Methicillin-resistant Staphylococcus aureus acquisition in healthcare workers with cystic fibrosis: a retrospective cross-sectional study.

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    Background People with cystic fibrosis (CF) may work in healthcare settings risking nosocomial pathogen acquisition. The aim of this study was to determine the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infection in adult healthcare workers with CF (HCWcf). Methods Data was collected in this observational study on MRSA acquisition from 405 CF patients attending an adult CF centre in Australia between 2001–2012. Demographic and clinical characteristics were compared between HCWcf and non-HCWcf. A sub-analysis was subsequently performed to compare demographic and clinical characteristics between those patients (HCWcf versus non-HCWcf) that acquired MRSA. We also investigated rates of chronic MRSA infection and the outcome of eradication treatment in HCWcf. Results A higher proportion of HCWcf acquired MRSA [n = 10/21] compared to non-HCWcf [n = 40/255] (P <0.001). The odds of MRSA acquisition were 8.4 (95 % CI, 3.0 – 23.4) times greater in HCWcf than non-HCWcf. HCWcf with MRSA were older (P = 0.02) and had better lung function (P = 0.009), yet hospitalisation rates were similar compared to non-HCWcf with MRSA. Chronic MRSA infection developed in 36/50 CF patients (HCWcf, n = 6; non-HCWcf, n = 30), with eradication therapy achieved in 5/6 (83 %) HCWcf. Conclusions The rate of MRSA incidence was highest in HCWcf and the workplace is a possible source of acquisition. Vocational guidance should include the potential for MRSA acquisition for CF patients considering healthcare professions

    The Power of Community: The Role of Community-Based Organizations in Mitigating COVID-19-Related Impacts on Well-Being Among South Florida's Minoritized Populations

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    The rapid closure of schools and businesses during the COVID-19 pandemic has had a significant impact in South Florida, highlighting diverse challenges to community well-being. Community-based organizations (CBOs) have served as a source of support for community members, particularly in stressful times. Using a combination of quantitative and qualitative methods, and in collaboration with Breakthrough Miami, a CBO committed to addressing the educational opportunity gap in Miami-Dade County, we conducted a study to assess challenges to the well-being of systematically minoritized families during the heart of the COVID-19 pandemic. The study included longitudinal survey data collected via ecological momentary assessment and in-depth interviews with Breakthrough Miami families to gather richer and nuanced data regarding indicators of well-being and CBO engagement. Quantitative results indicated that as perceived stress increased over time, so too did emotional and informational support. Follow-up qualitative interviews indicated that 100% of families identified Breakthrough Miami as a source of academic support during the pandemic. Additionally, families cited the important role Breakthrough Miami played beyond their standard academic programs and services in coping with the most significant sources of stress reported through the pandemic: meeting basic needs and threats to socioemotional well-being. Implications for CBOs are addressed

    The Power of Community: The Role of Community-Based Organizations in Mitigating COVID-19-Related Impacts on Well-Being Among South Florida's Minoritized Populations

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    The rapid closure of schools and businesses during the COVID-19 pandemic has had a significant impact in South Florida, highlighting diverse challenges to community well-being. Community-based organizations (CBOs) have served as a source of support for community members, particularly in stressful times. Using a combination of quantitative and qualitative methods, and in collaboration with Breakthrough Miami, a CBO committed to addressing the educational opportunity gap in Miami-Dade County, we conducted a study to assess challenges to the well-being of systematically minoritized families during the heart of the COVID-19 pandemic. The study included longitudinal survey data collected via ecological momentary assessment and in-depth interviews with Breakthrough Miami families to gather richer and nuanced data regarding indicators of well-being and CBO engagement. Quantitative results indicated that as perceived stress increased over time, so too did emotional and informational support. Follow-up qualitative interviews indicated that 100% of families identified Breakthrough Miami as a source of academic support during the pandemic. Additionally, families cited the important role Breakthrough Miami played beyond their standard academic programs and services in coping with the most significant sources of stress reported through the pandemic: meeting basic needs and threats to socioemotional well-being. Implications for CBOs are addressed

    Conceptual Links between Landscape Diversity and Diet Diversity:A Roadmap for Transdisciplinary Research

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    Malnutrition linked to poor quality diets affects at least 2 billion people. Forests, as well as agricultural systems linked to trees, are key sources of dietary diversity in rural settings. In the present article, we develop conceptual links between diet diversity and forested landscape mosaics within the rural tropics. First, we summarize the state of knowledge regarding diets obtained from forests, trees, and agroforests. We then hypothesize how disturbed secondary forests, edge habitats, forest access, and landscape diversity can function in bolstering dietary diversity. Taken together, these ideas help us build a framework illuminating four pathways (direct, agroecological, energy, and market pathways) connecting forested landscapes to diet diversity. Finally, we offer recommendations to fill remaining knowledge gaps related to diet and forest cover monitoring. We argue that better evaluation of the role of land cover complexity will help avoid overly simplistic views of food security and, instead, uncover nutritional synergies with forest conservation and restoration

    MiR-219a-5p Enriched Extracellular Vesicles Induce OPC Differentiation and EAE Improvement More Efficiently Than Liposomes and Polymeric Nanoparticles

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    Remyelination is a key aspect in multiple sclerosis pathology and a special effort is being made to promote it. However, there is still no available treatment to regenerate myelin and several strategies are being scrutinized. Myelination is naturally performed by oligodendrocytes and microRNAs have been postulated as a promising tool to induce oligodendrocyte precursor cell differentiation and therefore remyelination. Herein, DSPC liposomes and PLGA nanoparticles were studied for miR-219a-5p encapsulation, release and remyelination promotion. In parallel, they were compared with biologically engineered extracellular vesicles overexpressing miR-219a-5p. Interestingly, extracellular vesicles showed the highest oligodendrocyte precursor cell differentiation levels and were more effective than liposomes and polymeric nanoparticles crossing the blood–brain barrier. Finally, extracellular vesicles were able to improve EAE animal model clinical evolution. Our results indicate that the use of extracellular vesicles as miR-219a-5p delivery system can be a feasible and promising strategy to induce remyelination in multiple sclerosis patients.This work was supported by Carlos III Institute, (PI17/00189 and DTS15/00069), by Fondo Europeo de Desarrollo Regional—FEDER, by the Gipuzkoa Regional Council (DFG 15/006), by grant from the Basque Government (RIS3/DTS/2018222025), by the Department of Industry of the Basque Country (ELKARTEK 16/014), and the Spanish State Research Agency (SAF2017-87670-R) and Maria de Maeztu Units of Excellence Program Grant MDM-2017-0720). I.O.-Q., A.A. and L.I. were supported by the Department of Education of the Basque Government. IOQ and LAN were supported by EMBO short Term Fellowship Programme. LAN was supported by a Canadian graduate scholarship from the Canadian Institutes of Health Research (CGS-D CIHR).PRC was supported by Ikerbasque, the Basque Foundation for Science

    Primary cutaneous aggressive epidermotropic cytotoxic T-cell lymphomas: reappraisal of a provisional entity in the 2016 WHO classification of cutaneous lymphomas.

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    Primary cutaneous CD8-positive aggressive epidermotropic T-cell lymphoma is a rare and poorly characterized variant of cutaneous lymphoma still considered a provisional entity in the latest 2016 World Health Organization Classification of Cutaneous lymphomas. We sought to better characterize and provide diagnostic and therapeutic guidance of this rare cutaneous lymphoma. Thirty-four patients with a median age of 77 years (range 19-89 years) presented primarily with extensive annular necrotic plaques or tumor lesions with frequent mucous membrane involvement. The 5-year survival was 32% with a median survival of 12 months. A subset of 17 patients had a prodrome of chronic patches prior to the development of aggressive ulcerative lesions. We identified cases with lack of CD8 or αβ T-cell receptor expression yet with similar clinical and pathological presentation. Allogeneic stem cell transplantation provided partial or complete remissions in 5/6 patients. We recommend the term primary cutaneous aggressive epidermotropic cytotoxic T-cell lymphoma as this more broad designation better describes this clinical-pathologic presentation, which allows the inclusion of cases with CD8 negative and/or αβ/γδ T-cell receptor chain double-positive or double-negative expression. We have identified early skin signs of chronic patch/plaque lesions that are often misdiagnosed as eczema, psoriasis, or mycosis fungoides. Our experience confirms the poor prognosis of this entity and highlights the inefficacy of our standard therapies with the exception of allogeneic stem cell transplantation in selected cases
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