Publications by authors named "Christopher Stephens"

Modus Darwin redux.

Stud Hist Philos Sci

December 2024

How should we evaluate Darwin and Wallace's arguments for common ancestry over separate ancestry? Elliott Sober defends a likelihood reconstruction of Darwin's reasoning that he dubs modus Darwin: similarity, therefore common ancestry. One assumption of Sober's approach is that separate ancestors have traits that are probabilistically independent. I motivate an objection to this assumption by appeal to 19th century naturalist alternatives such as those of Geoffroy and Owen.

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Ornithologic study skins are specimens of avian skins that have been preserved by drying after removing the viscera and muscle. Because of the high value of study skins for scientific studies, specimens are shared among researchers. There is concern that study skins might be contaminated with high-consequence diseases such as highly pathogenic avian influenza virus (HPAIV) or Newcastle disease virus (NDV).

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Background: Non-narcotic intravenous medications may be a beneficial adjunct to oral multimodal pain regimens (MMPRs) which reduce but do not eliminate opioid exposure and prescribing after trauma. We hypothesized that the addition of a subdissociative ketamine infusion (KI) to a standardized oral MMPR reduces inpatient opioid exposure.

Methods: Eligible adult trauma patients admitted to the intermediate or intensive care unit were randomized upon admission to our institutional MMPR per usual care (UC) or UC plus subdissociative KI for 24 hours to 72 hours after arrival.

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Introduction: The inhaled anesthetic sevoflurane is an uncommon etiology of diffuse alveolar hemorrhage (DAH). As DAH typically presents in the inpatient, postoperative setting, it has been infrequently reported in the anesthesiology literature and, to our knowledge, has not been reported in the emergency medicine literature to date.

Case Report: We describe the presentation of a young, healthy male in respiratory distress to a busy urban emergency department (ED) after an outpatient surgical procedure.

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This article, the result of an Action Research project, describes the process of creating and testing a resource for assessing the contribution of chaplaincy in a British university setting, and the resultant insights and outcomes: organisational and individual learning, changes in chaplains' attitudes to monitoring and evaluation, and a resource which is perceived as having benefits and limitations. This article considers the evaluation process as applied to chaplaincy and offers a model for further testing.

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This article reports findings from an action research project in which a university chaplaincy team explored the desirability and viability of assessing their impact. It uncovers a complexity in chaplains' understandings about their role and - chief amongst their fears - belief that quantitative measures can be harmful to pastoral and spiritual work. It also reveals a sense of institutional accountability and a desire to engage with processes for determining and articulating chaplaincy's value.

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Drivers for wildlife infection are multiple and complex, particularly for vector-borne diseases. Here, we studied the role of host competence, geographic area provenance, and diversity of vector-host interactions as drivers of wild mammal infection risk to Trypanosoma cruzi, the aetiological agent of Chagas disease. We performed a systematic sampling of wild mammals in 11 states of Mexico, from 2017 to 2018.

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Obesity is a result of a long-term energy imbalance due to decisions associated with energy intake and expenditure. Those decisions fit the definition of heuristics: cognitive processes with a rapid and effortless implementation which can be very effective in dealing with scenarios that threaten an organism's viability. We study the implementation and evaluation of heuristics, and their associated actions, using agent-based simulations in environments where the distribution and degree of richness of energetic resources is varied in space and time.

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Until the late nineteenth century, denture baseplates and removable orthodontic appliances were usually made of gold. Though now largely forgotten, the discovery of vulcanised rubber was instrumental in making these forms of dental treatment widely available to the general public. While Charles Goodyear is recognised for his role in the development of vulcanite in America, that of Thomas Hancock in the UK is less well-known.

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(1) Background: Chagas disease is the main neglected tropical disease in America. It is estimated that around 6 million people are currently infected with the parasite in Latin America, and 25 million live in endemic areas with active transmission. The disease causes an estimated economic loss of USD 24 billion dollars annually, with a loss of 75,200 working years per year of life; it is responsible for around ~12,000 deaths annually.

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Although the utility of Ecological Niche Models (ENM) and Species Distribution Models (SDM) has been demonstrated in many ecological applications, their suitability for modelling epidemics or pandemics, such as SARS-Cov-2, has been questioned. In this paper, contrary to this viewpoint, we show that ENMs and SDMs can be created that can describe the evolution of pandemics, both in space and time. As an illustrative use case, we create models for predicting confirmed cases of COVID-19, viewed as our target "species", in Mexico through 2020 and 2021, showing that the models are predictive in both space and time.

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Introduction: The use of Y-90 radioembolization techniques has become a standard tool for the treatment of liver cancer and metastatic diseases that result in liver lesions. As there are only two approved forms of radioembolization therapy, the procedures for use are also fairly standardized even though exact international and interdepartmental procedures can vary. What has been less published over the years are the nuanced differences in delivery techniques and handling of the two available Y90 radioembolization therapies.

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Due to its central role in cell biology, the cytoskeleton is a key regulator of viral infection, influencing nearly every step of the viral life cycle. In this review, we will discuss the role of two key components of the cytoskeleton, namely the actin and microtubule networks in early HIV-1 infection. We will discuss key contributions to processes ranging from the attachment and entry of viral particles at the cell surface to their arrival and import into the nucleus and identify areas where further research into this complex relationship may yield new insights into HIV-1 pathogenesis.

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The potential benefits of incorporating biotic, as well as abiotic, predictors in niche and species distribution models (SDMs), as well as how to achieve this, is still debated, with their interpretability and explanatory potential being particularly questioned. It is therefore important to stress test modelling methodologies that include biotic factors against use cases where there is ample knowledge of the potential biotic component of the niche. Relatively well studied and important vector-borne diseases offer just such an opportunity, where knowledge of the agents involved in the transmission cycle -vectors and hosts- can serve to calibrate and test the niche model and corresponding SDM.

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Chagas disease, caused by the protozoa , is an important yet neglected disease that represents a severe public health problem in the Americas. Although the alteration of natural habitats and climate change can favor the establishment of new transmission cycles for the compound effect of human-modified landscapes and current climate change on the transmission dynamics of has until now received little attention. A better understanding of the relationship between these factors and presence is an important step towards finding ways to mitigate the future impact of this disease on human communities.

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Background: Evidence for effective pain management and opioid minimization of intravenous ketamine in elective surgery has been extrapolated to acutely injured patients, despite limited supporting evidence in this population. This trial seeks to determine the effectiveness of the addition of sub-dissociative ketamine to a pill-based, opioid-minimizing multi-modal pain regimen (MMPR) for post traumatic pain.

Methods: This is a single-center, parallel-group, randomized, controlled comparative effectiveness trial comparing a MMPR to a MMPR plus a sub-dissociative ketamine infusion.

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Sanitary disposal of contaminated organic material during recovery from an animal disease outbreak is costly and laborious. Characterizing the thermal stability of avian paramyxovirus type 1 (APMV-1; virulent APMV-1 strains cause Newcastle disease in poultry) will help inform risk assessments on the presence of viable virus on infected premises or in organic waste from infected premises. In some environments and housing types, heat may also be used as a decontamination method.

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Viral respiratory diseases, such as avian influenza, Newcastle disease, infectious bronchitis and infectious laryngotracheitis, have considerable negative economic implications for poultry. Ensuring the virus-free status of premises by environmental sampling after cleaning and disinfection is essential for lifting a quarantine and/or safely restocking the premises following an outbreak. The objectives of this study were to identify optimal sample collection devices and to determine the locations in poultry housing which are best for poultry respiratory virus sample collection.

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Although Lyme disease is currently classified as exotic in Mexico, recent studies have suggested that it might be endemic there. We assessed the potential risk for the establishment of transmission in Mexico. To identify the potential routes of spread, Complex Inference Networks were used initially to identify potential vector-host interactions between hard ticks () and migratory birds in the U.

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AbstractAirway management competency extends beyond technical skills to encompass a comprehensive approach to optimize patient outcomes. Initial and continuing education for airway management must therefore extend beyond a narrow focus on psychomotor skills and task completion to include appreciation of underlying pathophysiology, clinical judgment, and higher-order decision making. NAEMSP recommends:Active engagement in deliberate practice should be the guiding approach for developing and maintaining competence in airway management.

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Definitive management of trauma is not possible in the out-of-hospital environment. Rapid treatment and transport of trauma casualties to a trauma center are vital to improve survival and outcomes. Prioritization and management of airway, oxygenation, ventilation, protection from gross aspiration, and physiologic optimization must be balanced against timely patient delivery to definitive care.

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With the requirement to breed more productive crop plants in order to feed a growing global population, compounded by increasingly widespread resistance to pesticides exhibited by pathogens, plant immunity is becoming an increasingly important area of research. Of the genes that contribute to disease resistance, the wall-associated receptor-like kinases (WAKs) are increasingly shown to play a major role, in addition to their contribution to plant growth and development or tolerance to abiotic stresses. Being transmembrane proteins, WAKs form a central pillar of a plant cell's ability to monitor and interact with the extracellular environment.

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Five vaccines, including four inactivated, whole-virus water-in-oil adjuvanted vaccines and a commercial nonreplicating alphavirus-vectored RNA particle (RP) vaccine were evaluated in chickens for their ability to provide protection against challenge with a recent H7 highly pathogenic avian influenza virus (AIV) from the United States (A/turkey/IN/1403-1/2016 H7N8). One of the inactivated vaccines and the RP vaccine were prepared with A/turkey/IN/16-01571-6/2016 H7N8 low pathogenic AIV (LPAIV; TK/IN/16), which is identical to the challenge virus, except for the proteolytic cleavage site of the hemagglutinin protein. The remaining three inactivated vaccines were prepared with other North American H7 LPAIVs.

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Septoria tritici blotch (STB), caused by the fungus Zymoseptoria tritici, is one of the most economically important diseases of wheat. Recently, both factors of a gene-for-gene interaction between Z. tritici and wheat, the wheat receptor-like kinase Stb6 and the Z.

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