9095 research outputs found
Sort by
Thermophilic Carboxylesterases from Hydrothermal Vents of the Volcanic Island of Ischia Active on Synthetic and Biobased Polymers and Mycotoxins
Get PDFHydrothermal vents are geographically widespread and host microorganisms with robust enzymes useful in various industrial applications. We examined microbial communities and carboxylesterases of two terrestrial hydrothermal vents of the volcanic island of Ischia (Italy) predominantly composed of Firmicutes, Proteobacteria, and Bacteroidota. High-temperature enrichment cultures with the polyester plastics polyhydroxybutyrate and polylactic acid (PLA) resulted in an increase of Thermus and Geobacillus species and to some extent Fontimonas and Schleiferia species. The screening at 37 to 70°C of metagenomic fosmid libraries from above enrichment cultures identified three hydrolases (IS10, IS11, and IS12), all derived from yet-uncultured Chloroflexota and showing low sequence identity (33 to 56%) to characterized enzymes. Enzymes expressed in Escherichia coli exhibited maximal esterase activity at 70 to 90°C, with IS11 showing the highest thermostability (90% activity after 20-min incubation at 80°C). IS10 and IS12 were highly substrate promiscuous and hydrolyzed all 51 monoester substrates tested. Enzymes were active with PLA, polyethylene terephthalate model substrate, and mycotoxin T-2 (IS12). IS10 and IS12 had a classical α/β-hydrolase core domain with a serine hydrolase catalytic triad (Ser155, His280, and Asp250) in their hydrophobic active sites. The crystal structure of IS11 resolved at 2.92 Å revealed the presence of a N-terminal β-lactamase-like domain and C-terminal lipocalin domain. The catalytic cleft of IS11 included catalytic Ser68, Lys71, Tyr160, and Asn162, whereas the lipocalin domain enclosed the catalytic cleft like a lid and contributed to substrate binding. Our study identified novel thermotolerant carboxylesterases with a broad substrate range, including polyesters and mycotoxins, for potential applications in biotechnology
Characterizing seabed sediments at contrasting offshore renewable energy sites
Get PDFDue to the impacts of climate change, there is an urgent need to scale up existing, and develop novel, renewable energy technologies. Although there are many types of renewable energy technology, ocean renewable energy, including established offshore wind, and novel wave and tidal energy converters, offers many opportunities due to the abundance of the resource, availability of sea space, and (for tidal) predictability. However, the extraction of energy from the ocean environment will influence sediment dynamics and morphodynamics at various temporal and spatial scales. Detailed knowledge of seabed properties is also important for device installation, affecting foundation design and cabling. In this study, 36 seabed sediment samples were collected across a region of the Irish Sea extending from the west of Anglesey into Liverpool Bay up to a maximum distance of around 35 km offshore – a region where there are many existing and planned ocean renewable energy projects. Particle size analysis at quarter phi intervals was used to calculate the statistical properties of the seabed sediment samples, including Mean grain size, Sorting, Skewness and Kurtosis. These properties were compared against the outputs of wave (SWAN) and tidal (TELEMAC) models of the region to investigate the relationship between environmental variables and sediment characteristics, and to determine the impact and challenges of renewable energy technologies deployed in the region. Most of the sediments in the study area are medium sand, polymodal, very poorly sorted, coarse skewed, and very platykurtic. We found that mean water depth and peak current speed have the largest influence on Median grain size, and Sorting can be affected by tidal range, in addition to water depth and peak current speed. Moreover, minimal influence of wave climate was found on the sediments. A thorough discussion based on a literature review of the environmental issues of various energy converters (tidal energy converter (both individual and arrays), tidal barrage/lagoons, and wind turbines) was used to determine how devices in the study region, and at other sites throughout the world, would interact with sediment dynamics. We make recommendations on ways to minimize environmental impacts of ocean energy technologies
An exploration of the factors that influence admission, inclusion and support for learners with special educational needs in international schools
Get PDFAssessing landscape-scale patterns of activity and habitat-use by fallow deer (Dama dama) in the Elwy Valley region of North Wales, UK
Get PDFVegetated coastal ecosystems in the Southwestern Atlantic Ocean are an unexploited opportunity for climate change mitigation
Get PDFVegetated coastal ecosystems (mangroves, seagrasses, and saltmarshes, often called Blue Carbon ecosystems) store large carbon stocks. However, their regional carbon inventories, sequestration rates, and potential as natural climate change mitigation strategies are poorly constrained. Here, we systematically review organic carbon storage and accumulation rates in vegetated coastal ecosystems across the Central and Southwestern Atlantic, extending from Guyana (08.28°N) to Argentina (55.14°S). We estimate that 0.4 Pg organic carbon is stored in the region, which is approximately 2-5% of global carbon stores in coastal vegetated systems, and that they accumulate 0.5 to 3.9 Tg carbon annually. By ecosystem type, mangroves have the largest areal extent and contribute 70-80% of annual organic carbon accumulation, with Brazil hosting roughly 95% of mangrove stocks. Our findings suggest that organic carbon accumulation in the region is equivalent to 0.7 to 13% of global rates in vegetated coastal ecosystems, indicating the importance of conserving these ecosystems as a nature-based approach for mitigating and adapting to climate change
Diffusion in undoped and Cr-doped amorphous UO2
Get PDFUO2 fuel pellets are often doped with chromium oxide to obtain favourable properties such as higher density, improved thermal stability, large grain sizes, improved pellet-clad interaction margins, and increased fission gas retention during transients. Chromium has a low solubility limit in UO2, with past experimental work reporting solubility limits ranging between 0.004 to 0.06 wt.% Cr. Due to its low solubility, segregation of Cr ions to the grain boundary may occur. Further, the complexity of these boundaries may be high as observed in other ceramics resulting in disordered or amorphous regions along the boundary, affecting a range of material and operational properties of the fuel pellet. To assess these disordered regions, in this work we study amorphous undoped and Cr doped UO2 systems (containing 10–50 at.% Cr3+) that have been modelled using classical molecular dynamics methods incorporating Cr3+ into the well-used CRG potential library. Diffusion coefficients, pre-exponential factors, and activation energies for diffusion were computed for oxygen ions, assessing the impact of structure and extrinsic species on migration. Oxygen diffusion was observed to be much faster in the undoped amorphous system compared to its crystalline counterpart. Oxygen diffusion in doped systems decreased with increasing Cr concentration, highlighting the importance of additives to retain fission products and other migratory species
Protocol for a realist and social return on investment evaluation of the use of patient-reported outcomes in four value-based healthcare programmes
Get PDFINTRODUCTION: There is growing recognition that in order to remain sustainable, the UK's National Health Service must deliver the best patient outcomes within available resources. This focus on outcomes relative to cost is the basis of value-based healthcare (VBHC) and has led to interest in the recording of patient-reported outcome measures (PROMs) to measure patient perspectives on the impact of a health condition on their lives. Every health board in Wales is now required to collect PROMS as part of routine care. We will evaluate the VBHC programme implemented in a lead health board. The study aim is to understand what works about PROMs collection, for whom, in what contexts and why in a VBHC context. In addition, we will assess the social value of integrating PROMs collection into routine care.METHODS AND ANALYSIS: A three-stage mixed-methods study comprising a realist evaluation integrated with social return on investment (SROI) analysis across four conditions; Parkinson's disease, epilepsy, heart failure and cataract surgery. Workstream 1: Development of logic models, informed by a scoping review, documentary analysis, patient and public involvement (PPI), staff and key stakeholder engagement. Workstream 2: Realist evaluation building on multiple data sources from stages 1 to 3 to test and refine the programme theories that arise from the logic model development. Workstream 3: SROI analysis using interview data with patients, staff and carers, stakeholder and PPI engagement, anonymised routinely collected data, and questionnaires to populate a model that will explore the social value generated by the implementation of PROMs. Findings across stages will be validated with key stakeholders.ETHICS AND DISSEMINATION: The study is approved by Wales Research Ethics Committee #5 (22/WA/0044). Outcomes will be shared with key stakeholders, published in peer-reviewed journals and presented at national and international conferences.This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) licence, which permits others to distribute, remix, adapt, build on this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial.</p
Social and Economic Costs of Gambling Problems and Related Harm among UK Military Veterans
Get PDFIntroduction: Military veterans are at heightened risk of problem gambling. Little is known about the costs of problem gambling and related harm among United Kingdom (UK) Armed Forces (AF) veterans. We investigated the social and economic costs of gambling among a large sample of veterans through differences in healthcare and social service resource use compared with age-matched and gender-matched non-veterans from the UK AF Veterans’ Health and Gambling Study. Methods: An online survey measured sociodemographic characteristics, gambling experience and problem severity, mental health and healthcare resource utilisation. Healthcare provider, personal social service and societal costs were estimated as total adjusted mean costs and utility, with cost-consequence analysis of a single timepoint. Results: Veterans in our sample had higher healthcare, social service and societal costs and lower utility. Veterans had greater contacts with the criminal justice system, received more social service benefits, had more lost work hours and greater accrued debt. A cost difference of £590 (95% CI −£1016 to −£163) was evident between veterans with scores indicating problem gambling and those reporting no problems. Costs varied by problem gambling status. Conclusions: Our sample of UK AF veterans has higher healthcare, social service and societal costs than non-veterans. Veterans experiencing problem gambling are more costly but have no reduction in quality of life
How an Interest in Mindfulness Influences Linguistic Markers in Online Microblogging Discourse
Get PDFObjectivesThis study aimed to investigate the linguistic markers of an interest in mindfulness. Specifically, it examined whether individuals who follow mindfulness experts on Twitter use different language in their tweets compared to a random sample of Twitter users. This is a first step which may complement commonly used self-report measures of mindfulness with quantifiable behavioural metrics.MethodA linguistic analysis examined the association between an interest in mindfulness and linguistic markers in 1.87 million Twitter entries across 19,732 users from two groups, (1) a mindfulness interest group (n = 10,347) comprising followers of five mindfulness experts and (2) a control group (n = 9385) of a random selection of Twitter users. Text analysis software (Linguistic Inquiry and Word Count) was used to analyse linguistic markers associated with the categories and subcategories of mindfulness, affective processes, social orientation, and “being” mode of mind.ResultsAnalyses revealed an association between an interest in mindfulness and lexical choice. Specifically, tweets from the mindfulness interest group contained a significantly higher frequency of markers associated with mindfulness, positive emotion, happiness, and social orientation, and a significantly lower frequency of markers associated with negative emotion, past focus, present focus, future focus, family orientation, and friend orientation.ConclusionsResults from this study suggest that an interest in mindfulness is associated with more frequent use of certain language markers on Twitter. The analysis opens possible pathways towards developing more naturalistic methods of understanding and assessing mindfulness which may complement self-reporting methods
Focusing light with a metal film coated patchy particle
Get PDFMicrosphere-assisted super-resolution imaging is a promising technique that can significantly enhance the resolution of conventional optical microscopes. The focus of a classical microsphere is called photonic nanojet, which is a symmetric high-intensity electromagnetic field. Recently, patchy microspheres have been reported to have superior imaging performance than pristine microspheres, and coating microspheres with metal films leads to the formation of photonic hooks, which can enhance the imaging contrast of microspheres. Understanding the influence of metal patches on the near-field focusing of patchy particles is important for the rational design of a nanostructured microlens. In this work, we theoretically and experimentally showed that the light waves can be focused and engineered using patchy particles. When coating dielectric particles with Ag films, light beams with a hook-like structure or S-shaped structure can be generated. Simulation results show that the waveguide ability of metal films and the geometric asymmetry of patchy particles cause the formation of S-shaped light beams. Compared with classical photonic hooks, S-shaped photonic hooks have a longer effective length and a smaller beam waist at far-field region. Experiments were also carried out to demonstrate the generation of classical and S-shaped photonic hooks from patchy microspheres