Publications by authors named "Danielle Beckett"

Purpose: Canadian radiation oncology professionals have a strong history of involvement in global oncology initiatives worldwide. This pan-Canadian survey-based study was conducted to determine the current level of engagement of Canadian radiation oncologists (ROs) and medical physicists (MPs) in global oncology initiatives and broaden the development of these activities.

Materials And Methods: This was a cross-sectional study.

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Photosynthesis fuels primary production at the base of marine food webs. Yet, in many surface ocean ecosystems, diel-driven primary production is tightly coupled to daily loss. This tight coupling raises the question: which top-down drivers predominate in maintaining persistently stable picocyanobacterial populations over longer time scales? Motivated by high-frequency surface water measurements taken in the North Pacific Subtropical Gyre (NPSG), we developed multitrophic models to investigate bottom-up and top-down mechanisms underlying the balanced control of Prochlorococcus populations.

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The history of the British Isles and Ireland is characterized by multiple periods of major cultural change, including the influential transformation after the end of Roman rule, which precipitated shifts in language, settlement patterns and material culture. The extent to which migration from continental Europe mediated these transitions is a matter of long-standing debate. Here we study genome-wide ancient DNA from 460 medieval northwestern Europeans-including 278 individuals from England-alongside archaeological data, to infer contemporary population dynamics.

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The objective of these studies was to determine the effects of feeding a novel rumen-protected Lys (RP-Lys) product on plasma AA, lactational performance, and Lys bioavailability. To evaluate RP-Lys on lactation performance a corn-based diet (42.5% of corn silage and 21.

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Complex assemblages of microbes in the surface ocean are responsible for approximately half of global carbon fixation. The persistence of high taxonomic diversity despite competition for a small suite of relatively homogeneously distributed nutrients, that is, 'the paradox of the plankton', represents a long-standing challenge for ecological theory. Here we find evidence consistent with temporal niche partitioning of nitrogen assimilation processes over a diel cycle in the North Pacific Subtropical Gyre.

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This study aimed to develop empirically grounded recommendations and a coherent model of psychological care derived from the experiences and psychological care needs of COVID-19 frontline doctors, using semi-structured interviews and thematic analysis. Participants were UK frontline doctors specialising in Emergency Medicine, Anaesthetics, or Intensive Care ( = 31) purposively sampled for maximum variation on gender, specialty, ethnicity, and trauma-related distress; most worked in ICU during the pandemic (71%). Four themes were derived: (1) 'coping strategies', participants used many, including exercise, mindfulness, and "wait until it gets really bad"; (2) 'sources of support', participants valued embedded psychological support, digital services, and informal conversations with colleagues or family, though there was little opportunity; (3) 'organisational influences on wellbeing', participants reported a love-hate relationship for concepts like 'wellbeing', seen as important but insulting when basic workplace needs were unmet; (4) 'improving engagement with support', analysis suggests we must reduce physical and psychological barriers to access and encourage leaders to model psychologically supportive behaviours.

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The objective of this work was to characterize rumen volatile fatty acid (VFA) concentrations, rumen epithelial gene expression, and blood metabolite responses to diets with different starch and fiber sources. Six ruminally cannulated yearling Holstein heifers (body weight = 330 ± 11.3 kg) were arranged in a partially replicated Latin square experiment with 4 treatments consisting of different starch [barley (BAR) or corn (CRN)] and fiber [timothy hay (TH) or beet pulp (BP)] sources.

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The objective of this study was to investigate the effect of short-term elevated ambient temperature on ruminal volatile fatty acid (VFA) dynamics and rumen epithelium gene expression associated with the transport and metabolism of VFA. Eight ruminally cannulated Holstein heifers (200 kg) were used in a factorial, repeated measures experiment with two treatments and two periods. During the first period, animals were provided with feed ad libitum and housed at 20 °C.

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The West Africa Ebola virus disease outbreak of 2014-2016 demonstrated that responses to viral hemorrhagic fever epidemics must go beyond emergency stopgap measures and should incorporate high-quality medical care and clinical research. Optimal patient management is essential to improving outcomes, and it must be implemented regardless of geographical location or patient socioeconomic status. Coupling clinical research with improved care has a significant added benefit: Improved data quality and management can guide the development of more effective supportive care algorithms and can support regulatory approvals of investigational medical countermeasures (MCMs), which can alter the cycle of emergency response to reemerging pathogens.

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The rapid evolution of super-resolution light microscopy has narrowed the gap between light and electron microscopy, allowing the imaging of molecules and cellular structures at high resolution within their normal cellular and tissue context. Multimodal imaging approaches such as correlative light electron microscopy (CLEM) combine these techniques to create a tool with unique imaging capacity. However, these approaches are typically reserved for specialists, and their application to the analysis of neural tissue is challenging.

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The development of a novel database interrogating the patient management system in the Acute Medical Unit at Forth Valley Royal Hospital, Scotland, has allowed, for the first time, acquisition of reliable individual consultant-level process and outcome data over a 2-year period. These data have a number of uses, including understanding the level of variation between consultant physicians in AMU across key indicators, such as direct discharge percentage (67.5-44.

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Recent studies have revealed the importance of Ki-67 and the chromosome periphery in chromosome structure and segregation, but little is known about this elusive chromosome compartment. Here we used correlative light and serial block-face scanning electron microscopy, which we term 3D-CLEM, to model the entire mitotic chromosome complement at ultra-structural resolution. Prophase chromosomes exhibit a highly irregular surface appearance with a volume smaller than metaphase chromosomes.

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The Alzheimer's Disease Neuroimaging Initiative (ADNI) is an ongoing, longitudinal, multicenter study designed to develop clinical, imaging, genetic, and biochemical biomarkers for the early detection and tracking of Alzheimer's disease (AD). The initial study, ADNI-1, enrolled 400 subjects with early mild cognitive impairment (MCI), 200 with early AD, and 200 cognitively normal elderly controls. ADNI-1 was extended by a 2-year Grand Opportunities grant in 2009 and by a competitive renewal, ADNI-2, which enrolled an additional 550 participants and will run until 2015.

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Biotin protein ligases constitute a family of enzymes that catalyze the linkage of biotin to biotin-dependent carboxylases. In bacteria, these enzymes are functionally divided into two classes: the monofunctional enzymes that catalyze only biotin addition and the bifunctional enzymes that also bind to DNA to regulate transcription initiation. Biochemical and biophysical studies of the bifunctional Escherichia coli ligase suggest that several properties of the enzyme have evolved to support its additional regulatory role.

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Background: Trajectories of cognitive decline among elderly individuals are heterogeneous, and markers that have high reliability for predicting cognitive trajectories across a broad spectrum of the elderly population have yet to be identified.

Method: This study examined the utility of a variety of MRI-based brain measures, obtained at baseline, as predictors of subsequent declines in domain-specific measures of cognitive function in a cohort of 307 community-dwelling elderly individuals with varying degrees of cognitive impairment who were diverse across several relevant demographic variables and were evaluated yearly. Psychometrically matched measures of cognition were used to assess episodic memory, semantic memory, and executive function.

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We describe four patients with impaired platelet aggregation and 14C-serotonin secretion during stimulation with adenosine diphosphate (ADP), epinephrine, collagen, and platelet-activating factor. The response to arachidonic acid was normal in all patients with regard to aggregation and in three of the four with regard to 14C-serotonin secretion. The total platelet adenosine triphosphate (ATP) and ADP content and the ATP to ADP ratio was normal in all patients, thereby excluding storage pool deficiency as the cause of the secretion defect.

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