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1.
Article in English | MEDLINE | ID: mdl-38916099

ABSTRACT

Despite broad skepticism within the scientific community regarding paranormal phenomena such as ghosts and unidentified flying objects (UFOs), many members of the public believe in these phenomena. Previous studies have argued that viewing paranormal-themed television-including documentary, reality, and news programming-can cultivate such beliefs. In addition, recent research suggests that the online video-sharing platform YouTube may serve as an important source of messages about fringe phenomena. With that in mind, this study builds on theoretical accounts of genre-specific cultivation and social media affordances to examine how YouTube videos present paranormal topics and whether YouTube use predicts belief in the paranormal. A content analysis of 50 highly viewed YouTube videos about paranormal topics (25 about hauntings and 25 about UFOs) showed that a large majority of these videos featured paranormal claims and that a majority included purported footage of paranormal phenomena. Scientific sources appeared in only a quarter of UFO videos and almost no haunting videos, while government sources appeared in most UFO videos, but few haunting videos. An analysis of data from a survey of the U.S. public (n = 1,035), in turn, found that paranormal documentary or reality television viewing, paranormal news use, and YouTube use predicted belief in hauntings, controlling for a range of other media use variables and background factors. These results highlight the potential for video-sharing platforms such as YouTube to reinforce paranormal beliefs among the public.

3.
Anal Chem ; 95(34): 12867-12874, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37581365

ABSTRACT

We have employed a new approach to quantify the amount fraction of nitrous oxide in a synthetic air matrix gas used to prepare high-accuracy reference materials of the same component. Until now, this was the largest contributor to the measurement uncertainty of nitrous oxide in air reference materials at atmospheric amount fractions (∼330 nmol mol-1), as identified in a recent international comparison. A novel preconcentration method has resulted in a measurement of 363 pmol mol-1 of nitrous oxide in a synthetic air matrix gas with an expanded uncertainty of 27 pmol mol-1. This represents a significant breakthrough as using these developments with an optimized dilution hierarchy (to minimize the gravimetric uncertainty) promises to result in SI traceable reference materials with expanded uncertainties as low as 0.032% relative (k = 2). This supports the World Meteorological Organization-Global Atmosphere Watch network compatibility goal for underpinning atmospheric observations.

4.
BMC Med Educ ; 23(1): 21, 2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36631886

ABSTRACT

BACKGROUND: Good clinical examination skills can both increase the quality of patient care and reduce its cost. A previous study by our group demonstrated that face-to-face training is the gold standard for teaching these skills. It is unclear if high quality educational videos can augment this teaching. METHODS: Forty-two Medical Students naïve to large joint examination were recruited and block randomised to two groups. The control group had face-to-face teaching alone. The intervention group had their teaching augmented with a custom educational video accessed via a web portal. Participants were assessed on their examination of a large joint using a previously standardised assessment tool at baseline and 7 days post intervention. Assessors were blinded to intervention type. RESULTS: There was no significant difference in the mean baseline scores. Mean baseline scores were 3.35 (11.2%, SD = 2.2, SE = 0.49) for the face-to-face only group and 2.65 (8.8%, SD = 1.39, SE = 0.31) for the video adjunct group [p = 0.137]. There was a significant difference in the improvement in score after intervention between each group [p = 0.005]. The mean improvement in score was 15.42 (SD = 5.64, SE = 1.29) for the face-to-face only group and 20.68 (SD = 4.33,SE = 0.99) for the video adjunct group. CONCLUSION: When used as an adjunct to more traditional face-to-face teaching methods, a custom-made educational video significantly improves the teaching of clinical examination skills and there is a role for these resources in augmenting traditional teaching methods.


Subject(s)
Students, Medical , Humans , Clinical Competence , Educational Measurement , Learning , Physical Examination , Teaching , Education, Distance
5.
Anal Chem ; 94(44): 15207-15214, 2022 11 08.
Article in English | MEDLINE | ID: mdl-36300991

ABSTRACT

Novel traceable analytical methods and reference gas standards were developed for the detection of trace-level ammonia in biogas and biomethane. This work focused on an ammonia amount fraction at an upper limit level of 10 mg m-3 (corresponding to approximately 14 µmol mol-1) specified in EN 16723-1:2016. The application of spectroscopic analytical methods, such as Fourier transform infrared spectroscopy, cavity ring-down spectroscopy, and optical feedback cavity-enhanced absorption spectroscopy, was investigated. These techniques all exhibited the necessary ammonia sensitivity at the required 14 µmol mol-1 amount fraction. A 29-month stability study of reference gas mixtures of 10 µmol mol-1 ammonia in methane and synthetic biogas is also reported.


Subject(s)
Ammonia , Biofuels , Ammonia/analysis , Biofuels/analysis , Spectroscopy, Fourier Transform Infrared/methods , Feedback , Fourier Analysis
6.
Int J Spine Surg ; 16(1): 202-207, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35273109

ABSTRACT

BACKGROUND: The exact etiology of adolescent idiopathic scoliosis (AIS) is unknown, but recently, vitamin D has been suggested to be of importance in the pathophysiology of AIS. This article sought to (1) highlight the prevalence of vitamin D deficiency in patients undergoing corrective surgery for AIS within the United Kingdom and (2) evaluate the correlation and clinical relevance of preoperative back pain with vitamin D deficiency. METHODS: Data were collected on 201 consecutive patients undergoing corrective surgery for AIS. Baseline data included patient demographics, medical diagnoses, and standing preoperative Cobb angles. All patients had a preoperative 25-hydroxyvitamin D level recorded. One hundred ninety-six patients completed preoperative Scoliosis Research Society-22 outcome scores to quantify preoperative back pain. RESULTS: A total of 177 (89%) patients were young women, and the mean age at time of surgery was 14.9 years (13-18 years). All patients were diagnosed with AIS. The mean Cobb angles at time of surgery was 64°. Only 11 (5.5%) patients had "normal" vitamin D levels (>75 nmol/L), with 147 (74%) patients having deficient levels requiring treatment with supplementation. There was no correlation between vitamin D levels and preoperative Cobb angles (r s = -0.12), and there was a moderate correlation identified between the severity of preoperative vitamin D levels and preoperative back pain scores (r s =0.42). CONCLUSION: Vitamin D deficiency is common in patients with AIS; however, it is comparable to the national prevalence of vitamin D deficiency in healthy adolescent children. There was a strong correlation between preoperative back pain scores and the severity of vitamin D deficiency. These findings suggest that all patients with AIS should be screened for vitamin D deficiency and that supplementation where appropriate may lead to improved pain scores. CLINICAL RELEVANCE: If vitamin D is prevelant and if vitamin D deficiency is found to cause back pain, then there is an easy/cheap/safe treatement with supplementation.

7.
Rapid Commun Mass Spectrom ; 36(13): e9296, 2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35289456

ABSTRACT

RATIONALE: Information on the isotopic composition of nitrous oxide (N2 O) at natural abundance supports the identification of its source and sink processes. In recent years, a number of mass spectrometric and laser spectroscopic techniques have been developed and are increasingly used by the research community. Advances in this active research area, however, critically depend on the availability of suitable N2 O isotope Reference Materials (RMs). METHODS: Within the project Metrology for Stable Isotope Reference Standards (SIRS), seven pure N2 O isotope RMs have been developed and their 15 N/14 N, 18 O/16 O, 17 O/16 O ratios and 15 N site preference (SP) have been analysed by specialised laboratories against isotope reference materials. A particular focus was on the 15 N site-specific isotopic composition, as this measurand is both highly diagnostic for source appointment and challenging to analyse and link to existing scales. RESULTS: The established N2 O isotope RMs offer a wide spread in delta (δ) values: δ15 N: 0 to +104‰, δ18 O: +39 to +155‰, and δ15 NSP : -4 to +20‰. Conversion and uncertainty propagation of δ15 N and δ18 O to the Air-N2 and VSMOW scales, respectively, provides robust estimates for δ15 N(N2 O) and δ18 O(N2 O), with overall uncertainties of about 0.05‰ and 0.15‰, respectively. For δ15 NSP , an offset of >1.5‰ compared with earlier calibration approaches was detected, which should be revisited in the future. CONCLUSIONS: A set of seven N2 O isotope RMs anchored to the international isotope-ratio scales was developed that will promote the implementation of the recommended two-point calibration approach. Particularly, the availability of δ17 O data for N2 O RMs is expected to improve data quality/correction algorithms with respect to δ15 NSP and δ15 N analysis by mass spectrometry. We anticipate that the N2 O isotope RMs will enhance compatibility between laboratories and accelerate research progress in this emerging field.


Subject(s)
Nitrous Oxide , Calibration , Mass Spectrometry/methods , Nitrous Oxide/analysis , Oxygen Isotopes/analysis , Reference Standards
8.
Eur J Orthop Surg Traumatol ; 32(7): 1257-1263, 2022 Oct.
Article in English | MEDLINE | ID: mdl-34420150

ABSTRACT

PURPOSE: Intramedullary fixation of lateral malleolar fractures has increased in popularity recently with the introduction of the fibula nail. It has been proposed as an alternative fixation method in fractures to minimise soft tissue injury. The aim of this study was to evaluate the clinical and patient-reported outcomes of those who had an ankle fracture with concurrent significant soft tissue damage, treated with a fibula nail. METHODS: Details of patients who were managed at our institution using a fibula nail were obtained from the trauma database. The Acumed Fibula Rod System (FRS) was used in all cases. Those who were less than 12 months following injury were excluded. Patients attended a follow-up clinic for measurement of range of movement, radiographs, and to complete MOX-FQ and EQ-5D questionnaires. RESULTS: Twenty patients were identified. Eleven attended for review in person, and a further eight completed questionnaires (questionnaire response rate 95%). The mean age was 59 years (range 19-91). Twelve fractures were open, all of which were initially managed using an external fixator. One patient developed deep infection necessitating fusion. The mean MOX-FQ and EQ-5D scores were 53.6 and 0.649, respectively, at a median of 40 months post-injury. The mean EQ-VAS was 70. The range of movement of the affected side was significantly less than the unaffected side (p < 0.001 on paired t-test). CONCLUSION: This study suggests that the FRS offers a reliable and acceptable alternative fixation technique for patients who have significant soft tissue injuries.


Subject(s)
Ankle Fractures , Fracture Fixation, Intramedullary , Soft Tissue Injuries , Tibial Fractures , Adult , Aged , Aged, 80 and over , Ankle Fractures/complications , Ankle Fractures/diagnostic imaging , Ankle Fractures/surgery , Fibula/injuries , Fibula/surgery , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/methods , Fracture Fixation, Intramedullary/adverse effects , Fracture Fixation, Intramedullary/methods , Humans , Middle Aged , Retrospective Studies , Soft Tissue Injuries/surgery , Tibial Fractures/surgery , Treatment Outcome , Young Adult
9.
Anal Chem ; 93(36): 12147-12155, 2021 09 14.
Article in English | MEDLINE | ID: mdl-34464087

ABSTRACT

This Feature highlights the role of metrology, the science of measurement, in maintaining the infrastructure we all rely on for accurate chemical measurements. In particular, the recent change to the definition of the mole, the unit of chemistry, is explained.


Subject(s)
International System of Units
10.
New Phytol ; 225(4): 1470-1475, 2020 02.
Article in English | MEDLINE | ID: mdl-31665818

ABSTRACT

Trees are sources, sinks, and conduits for gas exchange between the atmosphere and soil, and effectively link these terrestrial realms in a soil-plant-atmosphere continuum. We demonstrated that naturally produced radon-222 (222 Rn) gas has the potential to disentangle the biotic and physical processes that regulate gas transfer between soils or plants and the atmosphere in field settings where exogenous tracer applications are challenging. Patterns in stem radon emissions across tree species, seasons, and diurnal periods suggest that plant transport of soil gases is controlled by plant hydraulics, whether by diffusion or mass flow via transpiration. We establish for the first time that trees emit soil gases during the night when transpiration rates are negligible, suggesting that axial diffusion is an important and understudied mechanism of plant and soil gas transmission.


Subject(s)
Carbon Dioxide/metabolism , Methane/metabolism , Plant Transpiration/physiology , Radon/metabolism , Trees/physiology , Biological Transport , Soil , Wood
11.
Data Brief ; 27: 104729, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31737767

ABSTRACT

We provide a dataset for our research article "Profitability, Efficiency and Inequality in Double Auction Markets with Snipers" [1]. This dataset [2] includes configuration files, raw output data, and replications of calculated metrics for our robot-populated market simulations. The raw data is subdivided into a hierarchy of folders corresponding to simulation treatment variables, in a 2 × 2 × 21 design for 84 treatments in total. Treatments variables include: (i) robot population ordering, either "primary" or "reverse"; (ii) two market schedules of agent's values and costs: equal-expected-profit "market 1" and unequal-expected-profit "market 2"; (iii) 21 robot populations identified by the number of Sniper Bots (0-20) on each side of the market. Each treatment directory contains a simulator input file and outputs for 10,000 periods of market data. The outputs include all acceptable buy and sell orders, all trades, profits for each agent, and market metrics such as efficiency-of-allocation, Gini coefficient, and price statistics. An additional public copy in Google Cloud is available for database query by users of Google BigQuery. The market simulator software is a private product created by Paul Brewer at Economic and Financial Technology Consulting LLC. Free open source modules are available for tech-savvy users at GitHub, NPM, and Docker Hub repositories and are sufficient to repeat the simulations. An easier-to-use paid market simulation product will eventually be available online from Econ1.Net. We provide instructions for repeating individual simulations using the free open source simulator and the free container tool Docker.

13.
Environ Sci Technol ; 53(8): 4088-4098, 2019 04 16.
Article in English | MEDLINE | ID: mdl-30829475

ABSTRACT

Results from the analysis of aqueous and solid-phase V speciation within samples collected from the Hazeltine Creek catchment affected by the August 2014 Mount Polley mine tailings dam failure in British Columbia, Canada, are presented. Electron microprobe and X-ray absorption near-edge structure (XANES) analysis found that V is present as V3+ substituted into magnetite and V3+ and V4+ substituted into titanite, both of which occur in the spilled Mount Polley tailings. Secondary Fe oxyhydroxides forming in inflow waters and on creek beds have V K-edge XANES spectra exhibiting E1/2 positions and pre-edge features consistent with the presence of V5+ species, suggesting sorption of this species on these secondary phases. PHREEQC modeling suggests that the stream waters mostly contain V5+ and the inflow and pore waters contain a mixture of V3+ and V5+. These data, and stream, inflow, and pore water chemical data, suggest that dissolution of V(III)-bearing magnetite, V(III)- and V(IV)-bearing titanite, V(V)-bearing Fe(-Al-Si-Mn) oxhydroxides, and V-bearing Al(OH)3 and/or clay minerals may have occurred. In the circumneutral pH environment of Hazeltine Creek, elevated V concentrations are likely naturally attenuated by formation of V(V)-bearing secondary Fe oxyhydroxide, Al(OH)3, or clay mineral colloids, suggesting that the V is not bioavailable. A conceptual model describing the origin and fate of V in Hazeltine Creek that is applicable to other river systems is presented.


Subject(s)
Vanadium , Water Pollutants, Chemical , British Columbia , Minerals , Rivers
14.
Anal Chem ; 91(8): 5310-5315, 2019 Apr 16.
Article in English | MEDLINE | ID: mdl-30917653

ABSTRACT

We have shown that an exchange dilution preparation method reduces the impact of surface adsorption of the target component in high-pressure gas mixtures used for underpinning measurements of amount-of-substance fraction. Gas mixtures are diluted in the same cylinder by releasing an aliquot of the parent mixture. Additional matrix gas is then added to the cylinder. This differs from conventional methods where dilutions are achieved by transferring the parent mixture to another cylinder, which then stores the final reference material. The benefit of this revolutionary approach is that losses due to adsorption to the walls of the cylinder and the valve are reduced as the parent mixture pacifies the surface with only a negligible relative change in amount-of-substance fraction. This development allows for preparation of gas reference materials with unprecedented uncertainties beyond the existing state of the art. It has significant implications for the preparation of high accuracy gas reference materials which underpin a broad range of requirements, particularly in atmospheric monitoring of carbon dioxide, where understanding the adsorption effects is the major obstacle to advancing the measurement science. It has the potential to remove the reliance on proprietary surface pretreatments as the method provides an in situ and consistent alternative.

15.
Mol Ther Methods Clin Dev ; 13: 145-153, 2019 Jun 14.
Article in English | MEDLINE | ID: mdl-30788383

ABSTRACT

Duchenne muscular dystrophy (DMD) is a devastating disease caused by mutations in the dystrophin gene that result in the complete absence of dystrophin protein. We have shown previously that recombinant mouse Galectin-1 treatment improves physiological and histological outcome measures in the mdx mouse model of DMD. Because recombinant human Galectin-1 (rHsGal1) will be used to treat DMD patients, we performed a dose-ranging study and intraperitoneal or intravenous delivery to determine the efficacy of rHsGal1 to improve preclinical outcome measures in mdx mice. Our studies showed that the optimal dose of rHsGal1 delivered intraperitoneally was 20 mg/kg and that this treatment improved muscle strength, sarcolemma stability, and capillary density in skeletal muscle. We next examined the efficacy of intravenous delivery and found that a dose of 2.5 mg/kg rHsGal1 was well tolerated and improved outcome measures in the mdx mouse model. Our studies identified that intravenous doses of rHsGal1 exceeding 2.5 mg/kg resulted in toxicity, indicating that dosing using this delivery mechanism will need to be carefully monitored. Our results support the idea that rHsGal1 treatment can improve outcome measures in the mdx mouse model and support further development as a potential therapeutic agent for DMD.

16.
Sensors (Basel) ; 19(4)2019 Feb 13.
Article in English | MEDLINE | ID: mdl-30781812

ABSTRACT

Technological advances in hyperspectral remote sensing have been widely applied in heavy metal soil contamination studies, as they are able to provide assessments in a rapid and cost-effective way. The present work investigates the potential role of combining field and laboratory spectroradiometry with geochemical data of lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) in quantifying and modelling heavy metal soil contamination (HMSC) for a floodplain site located in Wales, United Kingdom. The study objectives were to: (i) collect field- and lab-based spectra from contaminated soils by using ASD FieldSpec® 3, where the spectrum varies between 350 and 2500 nm; (ii) build field- and lab-based spectral libraries; (iii) conduct geochemical analyses of Pb, Zn, Cu and Cd using atomic absorption spectrometer; (iv) identify the specific spectral regions associated to the modelling of HMSC; and (v) develop and validate heavy metal prediction models (HMPM) for the aforementioned contaminants, by considering their spectral features and concentrations in the soil. Herein, the field- and lab-based spectral features derived from 85 soil samples were used successfully to develop two spectral libraries, which along with the concentrations of Pb, Zn, Cu and Cd were combined to build eight HMPMs using stepwise multiple linear regression. The results showed, for the first time, the feasibility to predict HMSC in a highly contaminated floodplain site by combining soil geochemistry analyses and field spectroradiometry. The generated models help for mapping heavy metal concentrations over a huge area by using space-borne hyperspectral sensors. The results further demonstrated the feasibility of combining geochemistry analyses with filed spectroradiometric data to generate models that can predict heavy metal concentrations.

17.
Article in English | MEDLINE | ID: mdl-32118079

ABSTRACT

Measurements of volatile organic compounds (VOCs) have been ongoing for decades to track growth rates and assist in curbing emissions of these compounds into the atmosphere. To accurately establish mole fraction trends and assess the role of these gas-phase compounds in atmospheric chemistry it is essential to have good calibration standards. A necessity and precursor to accurate VOC gas standards are the gas cylinders and the internal wall treatments that aid in maintaining the stability of the mixtures over long periods of time, measured in years. This paper will discuss the stability of VOC gas mixtures in different types of gas cylinders and internal wall treatments. Stability data will be given for 85 VOCs studied in gas mixtures by National Metrology Institutes and other agency laboratories. This evaluation of cylinder treatment materials is the outcome of an activity of the VOC Expert Group within the framework of the World Meteorological Organization (WMO) Global Atmospheric Watch (GAW) program.

18.
New Phytol ; 222(1): 18-28, 2019 04.
Article in English | MEDLINE | ID: mdl-30394559

ABSTRACT

Tree stems from wetland, floodplain and upland forests can produce and emit methane (CH4 ). Tree CH4 stem emissions have high spatial and temporal variability, but there is no consensus on the biophysical mechanisms that drive stem CH4 production and emissions. Here, we summarize up to 30 opportunities and challenges for stem CH4 emissions research, which, when addressed, will improve estimates of the magnitudes, patterns and drivers of CH4 emissions and trace their potential origin. We identified the need: (1) for both long-term, high-frequency measurements of stem CH4 emissions to understand the fine-scale processes, alongside rapid large-scale measurements designed to understand the variability across individuals, species and ecosystems; (2) to identify microorganisms and biogeochemical pathways associated with CH4 production; and (3) to develop a mechanistic model including passive and active transport of CH4 from the soil-tree-atmosphere continuum. Addressing these challenges will help to constrain the magnitudes and patterns of CH4 emissions, and allow for the integration of pathways and mechanisms of CH4 production and emissions into process-based models. These advances will facilitate the upscaling of stem CH4 emissions to the ecosystem level and quantify the role of stem CH4 emissions for the local to global CH4 budget.


Subject(s)
Carbon Cycle , Methane/metabolism , Plant Stems/metabolism , Trees/metabolism , Models, Biological , Water
19.
Glob Chang Biol ; 25(2): 373-385, 2019 02.
Article in English | MEDLINE | ID: mdl-30412646

ABSTRACT

Soil-atmosphere exchange significantly influences the global atmospheric abundances of carbon dioxide (CO2 ), methane (CH4 ), and nitrous oxide (N2 O). These greenhouse gases (GHGs) have been extensively studied at the soil profile level and extrapolated to coarser scales (regional and global). However, finer scale studies of soil aggregation have not received much attention, even though elucidating the GHG activities at the full spectrum of scales rather than just coarse levels is essential for reducing the large uncertainties in the current atmospheric budgets of these gases. Through synthesizing relevant studies, we propose that aggregates, as relatively separate micro-environments embedded in a complex soil matrix, can be viewed as biogeochemical reactors of GHGs. Aggregate reactivity is determined by both aggregate size (which determines the reactor size) and the bulk soil environment including both biotic and abiotic factors (which further influence the reaction conditions). With a systematic, dynamic view of the soil system, implications of aggregate reactors for soil-atmosphere GHG exchange are determined by both an individual reactor's reactivity and dynamics in aggregate size distributions. Emerging evidence supports the contention that aggregate reactors significantly influence soil-atmosphere GHG exchange and may have global implications for carbon and nitrogen cycling. In the context of increasingly frequent and severe disturbances, we advocate more analyses of GHG activities at the aggregate scale. To complement data on aggregate reactors, we suggest developing bottom-up aggregate-based models (ABMs) that apply a trait-based approach and incorporate soil system heterogeneity.


Subject(s)
Atmosphere/chemistry , Greenhouse Gases/analysis , Soil/chemistry
20.
Anal Chem ; 91(3): 1974-1979, 2019 Feb 05.
Article in English | MEDLINE | ID: mdl-30569711

ABSTRACT

The purity analysis of zero air is a significant contributor to the uncertainty in preparing reference materials of high impact greenhouse gases, limiting progress toward coherent and comparable measurements required to assess climate trends. We have produced a commutable synthetic zero air reference material with an oxygen, nitrogen, and argon matrix closely matching atmospheric composition. This is the critical step in preventing systematic biases from pressure broadening effects when using these reference materials to calibrate instruments based on optical spectroscopy. The amount fractions of carbon dioxide, methane, and carbon monoxide, which are present as minor impurities in the zero air reference material, have been accurately quantified using a novel dilution device that can generate gas mixtures of these components at trace amount fractions. These developments will have a significant impact on advancing the state of the art in high accuracy reference materials and for baseline calibration of spectroscopic instrumentation.

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