Publications by authors named "David M Richardson"

Background The majority of those aged 65 and older will visit the emergency department (ED) in the last six months of life. Knowing a patient's goals of care is important, and existing medical records do not always represent them well. We set out to determine the baseline availability of advance directives and goals of treatment in those ED patients at increased risk for mortality.

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Biological invasions are one of the major drivers of biodiversity decline and have been shown to have far-reaching consequences for society and the economy. Preventing the introduction and spread of alien species represents the most effective solution to reducing their impacts on nature and human well-being. However, implementing effective solutions requires a good understanding of where the species are established and how biological invasions develop over time.

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Invasions by nonnative insect species can massively disrupt ecological processes, often leading to serious economic impacts. Previous work has identified propagule pressure as important driver of the trend of increasing numbers of insect invasions worldwide. In the present article, we propose an alternative hypothesis-that insect invasions are being driven by the proliferation of nonnative plants, which create niches for insect specialists and facilitate their establishment outside their native ranges where their hosts are planted or are invasive.

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Article Synopsis
  • Citizen science initiatives, while cost-effective and capable of gathering vast amounts of data, face challenges regarding the quality and reliability of the information collected, particularly due to unverified observations.
  • A study developed a confidence scoring protocol for observations from iNaturalist, focusing on marine species in South Africa, revealing a strong relationship between observation accuracy and confidence scores.
  • The research underscores the need for expert verification of citizen science data, suggesting that the new confidence score can streamline the verification process and help minimize biases in data assessment.
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Unlabelled: Benefits provided by urban trees are increasingly threatened by non-native pests and pathogens. Monitoring of these invasions is critical for the effective management and conservation of urban tree populations. However, a shortage of professionally collected species occurrence data is a major impediment to assessments of biological invasions in urban areas.

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Cassava () is among the most important staple crops globally, with an imperative role in supporting the Sustainable Development Goal of 'Zero hunger'. In sub-Saharan Africa, it is cultivated mainly by millions of subsistence farmers who depend directly on it for their socio-economic welfare. However, its yield in some regions has been threatened by several diseases, especially the cassava brown streak disease (CBSD).

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  • The IPBES invasive alien species assessment is the first comprehensive global review focusing on the threats posed by invasive species to biodiversity and human wellbeing, synthesizing over 13,000 scientific and local knowledge sources.
  • It reveals significant and escalating threats from invasive alien species and outlines practical management strategies for addressing these challenges.
  • The assessment has garnered support from 143 member states, urging immediate action against biological invasions to protect ecosystems and communities worldwide.
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The Anthropocene is characterized by a rapid pace of environmental change and is causing a multitude of biotic responses, including those that affect the spatial distribution of species. Lagged responses are frequent and species distributions and assemblages are consequently pushed into a disequilibrium state. How the characteristics of environmental change-for example, gradual 'press' disturbances such as rising temperatures due to climate change versus infrequent 'pulse' disturbances such as extreme events-affect the magnitude of responses and the relaxation times of biota has been insufficiently explored.

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  • Many species have been introduced to new areas for their benefits, but some can cause harm while others may not.
  • Different strategies exist to manage these species, including banning harmful ones, minimizing damage while keeping benefits, or promoting safe species.
  • This article focuses on the "safe list" approach, which identifies low-risk alien species that can be used without worrying about negative effects, and offers guidance on creating and applying these lists for managing biological invasions.
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  • - The study of invasion ecology focuses on understanding what allows introduced species to transition from scarce to abundant, highlighting the distinction between invasiveness and abundance, which are interconnected but distinct concepts.
  • - A three-pronged framework is proposed that examines traits, environmental context, and propagule pressure to assess a species' invasiveness, which combines various factors to explain its potential growth and impact.
  • - The invasibility of a community is influenced by available niches and the interactions within the community, where predicting a species' success depends on understanding its functional traits and how these interact with environmental conditions and other species.
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  • Grasses (Poaceae) are highly invasive worldwide, with about 19% classified as invasive and nearly 38% as naturalized, indicating significant invasion success across many tribes.
  • The likelihood of a grass species becoming invasive is linked to its evolutionary traits and diversification rates, suggesting that some ancestral characteristics may predispose them to success in new environments.
  • Different biogeographic regions show varying levels of invasive grasses, with the temperate Palearctic having the highest ratio of invasives, highlighting the need for targeted management strategies based on evolutionary patterns.
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  • Plant invasions are increasing due to globalization, leading to significant ecological and economic impacts.
  • The paper focuses on community-level factors influencing plant invasiveness and ecosystem susceptibility, examining both intrinsic plant traits and environmental conditions.
  • It also emphasizes the role of human activities on local and global scales in shaping plant invasion patterns and their potential future trajectories.
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Plant invasions generate massive ecological and economic costs worldwide. Predicting their spatial dynamics is crucial to the design of effective management strategies and the prevention of invasions. Earlier studies highlighted the crucial role of long-distance dispersal in explaining the speed of many invasions.

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  • The paper introduces GIRAE (Generalised Impact = Range size × Abundance × per-unit Effect) as a method to estimate the total impact of alien species by examining their range, how abundant they are, and their specific effects on the environment.
  • Two approaches to apply GIRAE are proposed: the species-specific method which focuses on individual species at various sites, and the multi-species method which aggregates data across multiple species, making it easier to apply but less precise than the first.
  • Using South African data on plant invasion management costs, the study reveals significant variations in expenditure per area for different species, emphasizing the practical application of GIRAE in managing biological invasions.
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Restoring riparian ecosystems in human-dominated landscapes requires attention to complexity, and consideration of diverse drivers, social actors, and contexts. Addressing a Global North bias, this case study uses a mixed-method approach, integrating historical data, remote sensing techniques and stakeholder perceptions to guide restoration of a river in the Western Cape, South Africa. An analysis of aerial photographs of the riparian zone from 1953 to 2016 revealed that although anthropogenic land conversion happened primarily before the 1950s, several land use and land cover classes showed marked increases in area, including: waterbodies (+ 1074%), urban areas (+ 316%), alien weeds (+ 311%) and terrestrial alien trees (+ 79%).

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Community and invasion ecology have mostly grown independently. There is substantial overlap in the processes captured by different models in the two fields, and various frameworks have been developed to reduce this redundancy and synthesize information content. Despite broad recognition that community and invasion ecology are interconnected, a process-based framework synthesizing models across these two fields is lacking.

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Domestic and captive animals and cultivated plants should be recognised as integral components in contemporary ecosystems. They interact with wild organisms through such mechanisms as hybridization, predation, herbivory, competition and disease transmission and, in many cases, define ecosystem properties. Nevertheless, it is widespread practice for data on domestic, captive and cultivated organisms to be excluded from biodiversity repositories, such as natural history collections.

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Background And Aims: Invasive species may undergo rapid evolution despite very limited standing genetic diversity. This so-called genetic paradox of biological invasions assumes that an invasive species has experienced (and survived) a genetic bottleneck and then underwent local adaptation in the new range. In this study, we test how often Australian acacias (genus Acacia), one of the world's most problematic invasive tree groups, have experienced genetic bottlenecks and inbreeding.

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Article Synopsis
  • The article emphasizes the urgent need to address the biodiversity crisis and its impact on ecosystems.
  • It highlights the financial costs associated with invasive species and the significant consequences they have on native wildlife.
  • The role of human actions in exacerbating these issues is critical and should be a focal point in conservation efforts.
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Introduction: Disseminated tuberculosis (TB) is rare, affects any organ system, and presents mainly in immunocompromised populations. Typical presentation is non-specific, posing a challenge for diagnosis.

Case Report: This case presents an immunocompetent male presenting with severe headaches with meningeal signs.

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Article Synopsis
  • Understanding the future impacts of biological invasions is complex due to various environmental and socio-economic factors, making expert assessments vital in the absence of quantitative models.
  • An evaluation by 36 experts suggests that alien species invasions may rise by 20%-30%, posing significant threats to biodiversity, regardless of socioecological contexts.
  • Key drivers like transport, climate change, and socio-economic shifts will heavily influence these impacts, but proactive measures could lessen the consequences and contribute to global biodiversity goals.
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Article Synopsis
  • Biological invasions are a growing global issue driven by increased human connectivity and population, with invasive alien species spreading widely and negatively impacting ecosystems and livelihoods.
  • These invaders disrupt native species, reduce biodiversity, and alter ecosystem functions, leading to long-term ecological consequences that are often only recognized after they become established.
  • Despite successful biosecurity efforts in some countries, like Australia and New Zealand, many nations inadequately address invasions, highlighting the need for enhanced international collaboration and better implementation of management strategies to mitigate their effects.
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Purpose: We performed an emergency department (ED)-based substance use screening, motivational interview-based intervention, and treatment referral program with the goal of determining sex-specific outcomes. Specifically, in this quality improvement project, we aimed to determine whether there was a difference among sexes in the type of substances used; the frequency of positive screening results for substance use disorder; agreeing to an intervention; the type of follow-up evaluation, participation, and referral; and attempts to change substance use after intervention.

Methods: We prospectively studied a convenience sample of patients at 3 hospitals in Northeastern Pennsylvania from May 2017 through February 2018.

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