Publications by authors named "MacDonald F"

The Snowball Earth hypothesis predicts global ice cover; however, previous descriptions of Cryogenian (720-635 Ma) glacial deposits are limited to continental margins and shallow marine basins. The Tavakaiv (Tava) sandstone injectites and ridges in Colorado, USA, preserve a rare terrestrial record of Cryogenian low-latitude glaciation. Injectites, ridges, and chemically weathered crystalline rock display features characteristic of fluidization and pervasive deformation in a subglacial environment due to glacial loading, fluid overpressure, and repeated sand injection during meltwater events.

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Article Synopsis
  • Vasomotor symptoms (VMS) are common in breast cancer patients and can negatively impact quality of life and treatment adherence if not properly managed.
  • A study was conducted where patients selected from four interventions to manage their VMS, and effectiveness was measured using a validated scale at 6 weeks, with a new weighted score developed to assess change in symptoms.
  • Results indicated that the severity of VMS at the start influenced patients' perception of treatment effectiveness, and those with lower baseline symptoms didn't notice significant changes; thus, targeted interventions should focus on patients with moderate to high baseline symptoms.
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Interferon gamma (IFN) is a potent antiviral cytokine that can be produced by many innate and adaptive immune cells during infection. Currently, our understanding of which cells produce IFN and where they are located at different stages of an infection is limited. We have used reporter mice to investigate expression of mRNA in the lung and secondary lymphoid organs during and following influenza A virus (IAV) infection.

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The ~2,000-km-long Central Range of New Guinea is a hotspot of modern carbon sequestration due to the chemical weathering of igneous rocks with steep topography in the warm wet tropics. These high mountains formed in a collision between the Australian plate and ophiolite-bearing volcanic arc terranes, but poor resolution of the uplift and exhumation history has precluded assessments of the impact on global climate change. Here, we develop a palinspastic reconstruction of the Central Range orogen with existing surface geological constraints and seismic data to generate time-temperature paths and estimate volumes of eroded material.

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The Cryogenian Sturtian and Marinoan Snowball Earth glaciations bracket a nonglacial interval during which Demosponge and green-algal biomarkers first appear. To understand the relationships between environmental perturbations and early animal evolution, we measured sulfur and mercury isotopes from the Datangpo Formation from South China. Hg enrichment with positive ΔHg excursion suggests enhanced volcanism, potentially due to depressurization of terrestrial magma chambers during deglaciation.

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The flooding record of North America has been used to infer patterns of global erosion and sea level in deep time. Here, we utilize the geospatial dimension of the stratigraphic record provided by the Macrostrat database, and patterns of erosion from thermochronology, to resolve local tectonic subsidence from global sea level. We show that the flooding history of North America correlates in space and time with continent-facing subduction along active margins, consistent with subduction-driven dynamic topographic subsidence of the continental interior.

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Aims And Objectives: The purpose of this study was to assess the safety, feasibility and effectiveness of a nurse-led glaucoma assessment clinic service.

Background: Glaucoma is a group of serious, irreversible optic neuropathies that progressively damage the optic nerve resulting in blindness. Over 64.

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Ancient schwannomas are benign tumours arising from the neural sheath of peripheral, cranial and autonomic nerves. They are commonly situated in the inner ear and spine with pelvic manifestations being rare. We present the case of a 30-year-old patient, who presented with an abdominal mass.

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During the Cryogenian (720 to 635 Ma ago) Snowball Earth glaciations, ice extended to sea level near the equator. The cause of this catastrophic failure of Earth's thermostat has been unclear, but previous geochronology has suggested a rough coincidence of glacial onset with one of the largest magmatic episodes in the geological record, the Franklin large igneous province. U-Pb geochronology on zircon and baddeleyite from sills associated with the paleo-equatorial Franklin large igneous province in Arctic Canada record rapid emplacement between 719.

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Dexterous manipulation in robotic hands relies on an accurate sense of artificial touch. Here we investigate neuromorphic tactile sensation with an event-based optical tactile sensor combined with spiking neural networks for edge orientation detection. The sensor incorporates an event-based vision system (mini-eDVS) into a low-form factor artificial fingertip (the NeuroTac).

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Rationale: Patient support lines (PSLs) assist in triaging clinical problems, addressing patient queries, and navigating a complex multi-disciplinary oncology team. While providing support and training to the nursing staff who operate these lines is key, there is limited data on their experience and feedback.

Methods: We conducted a cross-sectional study of oncology nurses' (ONs') perspectives on the provision of care via PSLs at a tertiary referral cancer center via an anonymous, descriptive survey.

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Objective: To evaluate mastication in a group of patients with adolescent idiopathic scoliosis (AIS) with a control group, by means of the prevalence of reverse chewing cycles (RCCs).

Material And Methods: This study included a group of patients (N = 32; F = 24; M = 8; mean age ± SD = 14 ± 3 years) with a confirmed diagnosis of AIS and a group of control subjects (N = 32; F = 24; M = 8; mean age ± SD = 13 ± 6 years) without spinal disorders. Mastication was recorded with both a hard and a soft bolus, following a standardized protocol, and the prevalence of RCCs was compared between the groups.

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Purpose: Machine learning (ML) is a powerful tool for interrogating datasets and learning relationships between multiple variables. We utilized a ML model to identify those early breast cancer (EBC) patients at highest risk of developing severe vasomotor symptoms (VMS).

Methods: A gradient boosted decision model utilizing cross-sectional survey data from 360 EBC patients was created.

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Increasing awareness of the extent of preventable harm from healthcare has led to efforts to improve patient safety through a variety of efforts, including legislation. Extending legal privilege to quality and safety reviews leads to further harm for many patients, families and healthcare providers. The intentional isolation, silencing and exclusion after the incident undermines trust, prevents learning and impedes an opportunity to heal and recover for all those directly involved.

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Background: Despite the frequency of vasomotor symptoms (VMS) in patients with early breast cancer (EBC), their optimal management remains unknown. A patient survey was performed to determine perspectives on this important clinical challenge.

Methods: Patients with EBC experiencing VMS participated in an anonymous survey.

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Article Synopsis
  • Inherited conditions can cause cholestasis in newborns, and next-generation sequencing aids in diagnosing these conditions while revealing new gene-disease relationships.
  • The use of sequencing helps identify potential new treatment targets and patient groups that might benefit from specific therapies, but it also introduces challenges in interpreting genetic variants and predicting disease impact.
  • A study from 2010-2013 involving 222 infants with liver disease highlighted the complexities of genetic results, underlining the need for further research on how different traits and variants affect clinical outcomes in pediatric cholestasis.
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The rise of complex macroscopic life occurred during the Ediacaran Period, an interval that witnessed large-scale disturbances to biogeochemical systems. The current Ediacaran chronostratigraphic framework is of insufficient resolution to provide robust global correlation schemes or test hypotheses for the role of biogeochemical cycling in the evolution of complex life. Here, we present new radio-isotopic dates from Ediacaran strata that directly constrain key fossil assemblages and large-magnitude carbon cycle perturbations.

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The evolution of the global carbon and silicon cycles is thought to have contributed to the long-term stability of Earth's climate. Many questions remain, however, regarding the feedback mechanisms at play, and there are limited quantitative constraints on the sources and sinks of these elements in Earth's surface environments. Here we argue that the lithium-isotope record can be used to track the processes controlling the long-term carbon and silicon cycles.

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Purpose: Vasomotor symptoms (VMS) such as hot flashes and night sweats are common in breast cancer patients and can affect both quality of life and treatment adherence. However, there is limited practical data to guide clinicians in the optimal selection of therapeutic strategies. A survey of health care providers was performed to better understand perspectives and prescribing practices for managing this problem.

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Interleukin 9 (IL-9)-producing helper T (Th9) cells are essential for inducing anti-tumor immunity and inflammation in allergic and autoimmune diseases. Although transcription factors that are essential for Th9 cell differentiation have been identified, other signaling pathways that are required for their generation and functions are yet to be explored. Here, we identify that Epidermal Growth Factor Receptor (EGFR) is essential for IL-9 induction in helper T (Th) cells.

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The question of whether orthodontic therapy by means of rapid palatal expansion (RPE) affects the spine during development is important in clinical practice. RPE is an expansive, fixed therapy conducted with heavy forces to separate the midpalatal suture at a rate of 0.2-0.

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