45 research outputs found

    The spatial distribution and composition of microplastics in Placentia Bay, Newfoundland and Labrador

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    As part of a baseline study for Placentia Bay, one of Newfoundland's prominent fishing regions, I investigated the spatial distribution and characteristics of microplastics. I collected water samples from the surface at nine open-water locations and sediment samples at six locations in the sediment layer. Microplastics were examined under a microscope, and a subset of samples underwent Raman microspectroscopy for chemical identification To tailor methods specifically to the water and sediment samples from Placentia Bay, I conducted method tests. Published methods proved unreliable, as a lack of standardized methodology was evident. Water column samples required an extended digestion time of 24 hours with hydrogen peroxide and acetic acid due to their POC-rich nature. In sediment samples, microplastics were isolated using a sodium tungstate dihydrate solution. . The highest concentrations of microplastics in the water column were identified on the eastern side of the bay, with fibers being the predominant shape and polyethylene as the dominant polymer type. Raman spectroscopy was employed to confirm microplastics and evaluate the reliability of visual identification. 50% of fragments and 21% of fibers were non-plastic, highlighting the limitations of relying solely on visual identification for characterizing microplastics

    Exploring students’ epistemological knowledge of models and modelling in science:results from a teaching/learning experience on climate change

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    The scientific community has been debating climate change for over two decades. In the light of certain arguments put forward by the aforesaid community, the EU has recommended a set of innovative reforms to science teaching such as incorporating environmental issues into the scientific curriculum, thereby helping to make schools a place of civic education. However, despite these European recommendations, relatively little emphasis is still given to climate change within science curricula. Climate change, although potentially engaging for students, is a complex topic that poses conceptual difficulties and emotional barriers, as well as epistemological challenges. Whilst the conceptual and emotional barriers have already been the object of several studies, students\u2019 reactions to the epistemological issues raised by climate changes have so far been rarely explored in science education research and thus are the main focus of this paper. This paper describes a study concerning the implementation of teaching materials designed to focus on the epistemological role of \u2018models and the game of modelling\u2019 in science and particularly when dealing with climate change. The materials were implemented in a course of 15 hours (five 3-hour lessons) for a class of Italian secondary-school students (grade 11; 16\u201317 years old). The purpose of the study is to investigate students\u2019 reactions to the epistemological dimension of the materials, and to explore if and how the material enabled them to develop their epistemological knowledge on models

    The Wicked Problem of microplastics – an interdisciplinary solution

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    WICKED PROBLEMS Traditional university education equips students with deep discipline knowledge and skills. However, our planet faces many challenges and wicked problems that require solutions to span disciplines and need graduates with essential transferable skills such as critical thinking, problem solving, prioritisation, communication and teamwork. Our students require a flexible, open mindset that facilitates interdisciplinary problem solving. One such challenge is the microplastics pollution which has extended into all corners of the globe. This messy, multifaceted problem lacks clear boundaries and defies simple solutions. Such complex problems are best tackled with interdisciplinary approaches to break down boundaries between disciplines and generate new ways of thinking and integrated solutions. AN INTERDISCIPLINARY APPROACH In 2022, academics from the Science Schools within the Faculty of Science, Medicine Health at the University of Wollongong (UOW) partnered with undergraduate students, industry professionals and academics across other faculties to design and deliver a one-day interdisciplinary education event. This extracurricular activity brought together over thirty, mostly third year, undergraduate students across science, law, environmental engineering, public health, and geography and sustainable communities to tackle the issue of microplastics, and their impact on environmental and human health. The students were allocated to teams and provided a schema to identify one critical source or pathway of microplastics waste and to explore solutions to reduce its impact. Students used the strengths of their varying disciplines and considered the role of individuals, local government, Non-Government Organisations (NGOs), industry and/or corporations when developing a solution through a one-slide infographic/poster and three-minute pitch. IMPACTS ON STUDENT DEVELOPMENT Our initiative was purposefully aimed at third-year students to provide further work-integrated learning (WIL) opportunities pre-graduation and to focus on developing skills that may have been impacted during the pandemic and the move to online activities. Student feedback was very positive and highlighted key learnings about the benefits of networking, students putting themselves back out there socially and professionally, alongside combining expertise and developing creativity. Students enjoyed the topic area and gaining experience and confidence in presenting their ideas to others. At the same time student attendees, and our student partners gained recognition of their extracurricular involvement through a UOWx certification, noting key employability skills developed through their involvement. Students were also invited to a field trip to sample microplastics at a local beach in partnership with the Australian Microplastics Assessment Project (AUSMAP). The ongoing challenge is to work towards embedding such opportunities within curricula which involves navigating complex university governance structures, internal funding and staff models, course constraints and timetabling. The presenters welcome discussion

    Ischaemic stroke, haemorrhage and mortality in elderly patients with chronic kidney disease newly started on anticoagulation for atrial fibrillation: a population-based study from UK primary care

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    Objective To assess the association between anticoagulation, ischaemic stroke, gastrointestinal and cerebral haemorrhage, and all cause mortality in older people with atrial fibrillation and chronic kidney disease. Design Propensity matched, population based, retrospective cohort analysis from January 2006 through December 2016. Setting The Royal College of General Practitioners Research and Surveillance Centre database population of almost 2.73 million patients from 110 general practices across England and Wales. Participants Patients aged 65 years and over with a new diagnosis of atrial fibrillation and estimated glomerular filtration rate (eGFR) of <50 mL/min/1.73m2, calculated using the chronic kidney disease epidemiology collaboration creatinine equation. Patients with a previous diagnosis of atrial fibrillation or receiving anticoagulation in the preceding 120 days were excluded, as were patients requiring dialysis and recipients of renal transplants. Intervention Receipt of an anticoagulant prescription within 60 days of atrial fibrillation diagnosis. Main outcome measures Ischaemic stroke, cerebral or gastrointestinal haemorrhage, and all cause mortality. Results 6977 patients with chronic kidney disease and newly diagnosed atrial fibrillation were identified, of whom 2434 were on anticoagulants within 60 days of diagnosis and 4543 were not. 2434 pairs were matched using propensity scores by exposure to anticoagulant or none and followed for a median of 506 days. The crude rates for ischaemic stroke and haemorrhage were 4.6 and 1.2 after taking anticoagulants and 1.5 and 0.4 in patients who were not taking anticoagulant per 100 person years, respectively. The hazard ratios for ischaemic stroke, haemorrhage, and all cause mortality for those on anticoagulants were 2.60 (95% confidence interval 2.00 to 3.38), 2.42 (1.44 to 4.05), and 0.82 (0.74 to 0.91) compared with those who received no anticoagulation. Conclusion Giving anticoagulants to older people with concomitant atrial fibrillation and chronic kidney disease was associated with an increased rate of ischaemic stroke and haemorrhage but a paradoxical lowered rate of all cause mortality. Careful consideration should be given before starting anticoagulants in older people with chronic kidney disease who develop atrial fibrillation. There remains an urgent need for adequately powered randomised trials in this population to explore these findings and to provide clarity on correct clinical management

    A cholinergic neuroskeletal interface promotes bone formation during postnatal growth and exercise.

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    The autonomic nervous system is a master regulator of homeostatic processes and stress responses. Sympathetic noradrenergic nerve fibers decrease bone mass, but the role of cholinergic signaling in bone has remained largely unknown. Here, we describe that early postnatally, a subset of sympathetic nerve fibers undergoes an interleukin-6 (IL-6)-induced cholinergic switch upon contacting the bone. A neurotrophic dependency mediated through GDNF-family receptor-α2 (GFRα2) and its ligand, neurturin (NRTN), is established between sympathetic cholinergic fibers and bone-embedded osteocytes, which require cholinergic innervation for their survival and connectivity. Bone-lining osteoprogenitors amplify and propagate cholinergic signals in the bone marrow (BM). Moderate exercise augments trabecular bone partly through an IL-6-dependent expansion of sympathetic cholinergic nerve fibers. Consequently, loss of cholinergic skeletal innervation reduces osteocyte survival and function, causing osteopenia and impaired skeletal adaptation to moderate exercise. These results uncover a cholinergic neuro-osteocyte interface that regulates skeletogenesis and skeletal turnover through bone-anabolic effects

    Venous access devices for the delivery of long-term chemotherapy: the CAVA three-arm RCT

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    Background: Venous access devices are used for patients receiving long-term chemotherapy. These include centrally inserted tunnelled catheters or Hickman-type devices (Hickman), peripherally inserted central catheters (PICCs) and centrally inserted totally implantable venous access devices (PORTs). Objectives: To evaluate the clinical effectiveness, safety, cost-effectiveness and acceptability of these devices for the central delivery of chemotherapy. Design: An open, multicentre, randomised controlled trial to inform three comparisons: (1) peripherally inserted central catheters versus Hickman, (2) PORTs versus Hickman and (3) PORTs versus peripherally inserted central catheters. Pre-trial and post-trial qualitative research and economic evaluation were also conducted. Setting: This took place in 18 UK oncology centres. Participants: Adult patients (aged ≥ 18 years) receiving chemotherapy (≥ 12 weeks) for either a solid or a haematological malignancy were randomised via minimisation. Interventions: Hickman, peripherally inserted central catheters and PORTs. Primary outcome: A composite of infection (laboratory confirmed, suspected catheter related and exit site infection), mechanical failure, venous thrombosis, pulmonary embolism, inability to aspirate blood and other complications in the intention-to-treat population. Results: Overall, 1061 participants were recruited to inform three comparisons. First, for the comparison of peripherally inserted central catheters (n = 212) with Hickman (n = 212), it could not be concluded that peripherally inserted central catheters were significantly non-inferior to Hickman in terms of complication rate (odds ratio 1.15, 95% confidence interval 0.78 to 1.71). The use of peripherally inserted central catheters compared with Hickman was associated with a substantially lower cost (–£1553) and a small decrement in quality-adjusted life-years gained (–0.009). Second, for the comparison of PORTs (n = 253) with Hickman (n = 303), PORTs were found to be statistically significantly superior to Hickman in terms of complication rate (odds ratio 0.54, 95% confidence interval 0.37 to 0.77). PORTs were found to dominate Hickman with lower costs (–£45) and greater quality-adjusted life-years gained (0.004). This was alongside a lower complications rate (difference of 14%); the incremental cost per complication averted was £1.36. Third, for the comparison of PORTs (n = 147) with peripherally inserted central catheters (n = 199), PORTs were found to be statistically significantly superior to peripherally inserted central catheters in terms of complication rate (odds ratio 0.52, 95% confidence interval 0.33 to 0.83). PORTs were associated with an incremental cost of £2706 when compared with peripherally inserted central catheters and a decrement in quality-adjusted life-years gained (–0.018) PORTs are dominated by peripherally inserted central catheters: alongside a lower complications rate (difference of 15%), the incremental cost per complication averted was £104. The qualitative work showed that attitudes towards all three devices were positive, with patients viewing their central venous access device as part of their treatment and recovery. PORTs were perceived to offer unique psychological benefits, including a greater sense of freedom and less intrusion in the context of personal relationships. The main limitation was the lack of adequate power (54%) in the non-inferiority comparison between peripherally inserted central catheters and Hickman. Conclusions: In the delivery of long-term chemotherapy, peripherally inserted central catheters should be considered a cost-effective option when compared with Hickman. There were significant clinical benefits when comparing PORTs with Hickman and with peripherally inserted central catheters. The health economic benefits were less clear from the perspective of incremental cost per quality-adjusted life-years gained. However, dependent on the willingness to pay, PORTs may be considered to be cost-effective from the perspective of complications averted. Future work: The deliverability of a PORTs service merits further study to understand the barriers to and methods of improving the service. Trial registration: This trial is registered as ISRCTN44504648. Funding: This project was funded by the National Institute for Health Research (NHIR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 47. See the NIHR Journals Library website for further project information

    The need for laboratory work to aid in the understanding of exoplanetary atmospheres

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    Advancements in our understanding of exoplanetary atmospheres, from massive gas giants down to rocky worlds, depend on the constructive challenges between observations and models. We are now on a clear trajectory for improvements in exoplanet observations that will revolutionize our ability to characterize the atmospheric structure, composition, and circulation of these worlds. These improvements stem from significant investments in new missions and facilities, such as JWST and the several planned ground-based extremely large telescopes. However, while exoplanet science currently has a wide range of sophisticated models that can be applied to the tide of forthcoming observations, the trajectory for preparing these models for the upcoming observational challenges is unclear. Thus, our ability to maximize the insights gained from the next generation of observatories is not certain. In many cases, uncertainties in a path towards model advancement stems from insufficiencies in the laboratory data that serve as critical inputs to atmospheric physical and chemical tools. We outline a number of areas where laboratory or ab initio investigations could fill critical gaps in our ability to model exoplanet atmospheric opacities, clouds, and chemistry. Specifically highlighted are needs for: (1) molecular opacity linelists with parameters for a diversity of broadening gases, (2) extended databases for collision-induced absorption and dimer opacities, (3) high spectral resolution opacity data for relevant molecular species, (4) laboratory studies of haze and condensate formation and optical properties, (5) significantly expanded databases of chemical reaction rates, and (6) measurements of gas photo-absorption cross sections at high temperatures. We hope that by meeting these needs, we can make the next two decades of exoplanet science as productive and insightful as the previous two decades.Publisher PD

    The Developing Human Connectome Project neonatal data release

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    The Developing Human Connectome Project has created a large open science resource which provides researchers with data for investigating typical and atypical brain development across the perinatal period. It has collected 1228 multimodal magnetic resonance imaging (MRI) brain datasets from 1173 fetal and/or neonatal participants, together with collateral demographic, clinical, family, neurocognitive and genomic data from 1173 participants, together with collateral demographic, clinical, family, neurocognitive and genomic data. All subjects were studied in utero and/or soon after birth on a single MRI scanner using specially developed scanning sequences which included novel motion-tolerant imaging methods. Imaging data are complemented by rich demographic, clinical, neurodevelopmental, and genomic information. The project is now releasing a large set of neonatal data; fetal data will be described and released separately. This release includes scans from 783 infants of whom: 583 were healthy infants born at term; as well as preterm infants; and infants at high risk of atypical neurocognitive development. Many infants were imaged more than once to provide longitudinal data, and the total number of datasets being released is 887. We now describe the dHCP image acquisition and processing protocols, summarize the available imaging and collateral data, and provide information on how the data can be accessed
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