258 research outputs found
An exploration of the effectiveness of artificial mini-magnetospheres as a potential solar storm shelter for long term human space missions
If mankind is to explore the solar system beyond the confines of our Earth and Moon the problem of radiation protection must be addressed. Galactic cosmic rays and highly variable energetic solar particles are an ever-present hazard in interplanetary space.
Electric and/or magnetic fields have been suggested as deflection shields in the past, but these treated space as an empty vacuum. In fact it is not empty. Space contains a plasma known as the solar wind; a constant flow of protons and electrons coming from the Sun.
In this paper we explore the effectiveness of a “mini-magnetosphere” acting as a radiation protection shield. We explicitly include the plasma physics necessary to account for the solar wind and its induced effects. We show that, by capturing/containing this plasma, we enhance the effectiveness of the shield. Further evidence to support our conclusions can be obtained from studying naturally occurring “mini-magnetospheres” on the Moon. These magnetic anomalies (related to “lunar swirls”) exhibit many of the effects seen in laboratory experiments and computer simulations. If shown to be feasible, this technology could become the gateway to manned exploration of interplanetary space
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Healthcare utilization among migrants to the UK: cross-sectional analysis of two national surveys
Funder: The Health FoundationObjective: To contribute objective evidence on health care utilization among migrants to the UK to inform policy and service planning. Methods: We analysed data from Understanding Society, a household survey with fieldwork from 2015 to 2017, and the European Health Interview Survey with data collected between 2013 and 2014. We explored health service utilization among migrants to the UK across primary care, inpatient admissions and maternity care, outpatient care, mental health, dental care and physiotherapy. We adjusted for age, sex, long-term health conditions and time since moving to the UK. Results: Health care utilization among migrants to the UK was lower than utilization among the UK-born population for all health care dimensions except inpatient admissions for childbirth; odds ratio (95%CI) range 0.58 (0.50–0.68) for dental care to 0.88 (0.78–0.98) for primary care). After adjusting for differences in age and self-reported health, these differences were no longer observed, except for dental care (odds ratio 0.57, 95%CI 0.49–0.66, P < 0.001). Across primary care, outpatient and inpatient care, utilization was lower among those who had recently migrated, increasing to the levels of the nonmigrant population after 10 years or more since migrating to the UK. Conclusions: This study finds that newly arrived migrants tend to utilize less health care than the UK population and that this pattern was at least partly explained by better health, and younger age. Our findings contribute nationally representative evidence to inform public debate and decision-making on migration and health
A four-helix bundle stores copper for methane oxidation
Methane-oxidising bacteria (methanotrophs) require large quantities of copper for the membrane-bound (particulate) methane monooxygenase (pMMO). Certain methanotrophs are also able to switch to using the iron-containing soluble MMO (sMMO) to catalyse methane oxidation, with this switchover regulated by copper. MMOs are Nature’s primary biological mechanism for suppressing atmospheric levels of methane, a potent greenhouse gas. Furthermore, methanotrophs and MMOs have enormous potential in bioremediation and for biotransformations producing bulk and fine chemicals, and in bioenergy, particularly considering increased methane availability from renewable sources and hydraulic fracturing of shale rock. We have discovered and characterised a novel copper storage protein (Csp1) from the methanotroph Methylosinus trichosporium OB3b that is exported from the cytosol, and stores copper for pMMO. Csp1 is a tetramer of 4-helix bundles with each monomer binding up to 13 Cu(I) ions in a previously unseen manner via mainly Cys residues that point into the core of the bundle. Csp1 is the first example of a protein that stores a metal within an established protein-folding motif. This work provides a detailed insight into how methanotrophs accumulate copper for the oxidation of methane. Understanding this process is essential if the wide-ranging biotechnological applications of methanotrophs are to be realised. Cytosolic homologues of Csp1 are present in diverse bacteria thus challenging the dogma that such organisms do not use copper in this location
A cross-sectional exploratory analysis between pet ownership and sleep, exercise, health and neighborhood perceptions : The Whitehall II cohort study
A cross-sectional exploratory analysis between pet ownership and sleep, exercise, health and neighbourhood perceptions: The Whitehall II cohort study
Gill Mein (corresponding author), Robert Grant. Faculty of Health, Social Care and Education. Kingston University and St George’s University of London
Background: To explore associations between pets, and specifically dog ownership and sleep, health, exercise and neighbourhood.
Methods: Cross sectional examination of 6575 participants of the Whitehall II study aged between 59-79 years. We used self-assessed measurement scales of the Short Form (SF36), General Health Questionnaire (GHQ), Control, Autonomy, Self-realisation and Pleasure (CASP), Centre for Epidemiologic Studies Depression Scale (CES-D), sleep, exercise, and perceptions of local neighbourhood. In addition the Mini Mental State Examination which is administered to test global cognitive status (MMSE)
Results: We found 2/7 people owned a pet and of those 64% were “very” attached to their pet. Mild exercise in metabolic equivalents (MET-hours) was significantly higher in pet owners than non-owners (median 27.8 (IQR 18.1 to 41.8) vs 25.7 (IQR 16.8 to 38.7), p=0.0001), and in dog owners than other pets (median 32.3 (IQR 20.8 to 46.1) vs 25.6 (IQR 16.8 to 38.5), p<0.0001). Moderate exercise was also significantly higher in pet owners than non pet owners (median 11.8 (IQR 4.2 to 21.9) vs 9.8 (IQR 2.8 to 19.5), p<0.0001), and dog owners than owners of other pets (median 12.3 (IQR 4.2 to 22.2) vs 10.1 (3.1 to 20.0), p=0.0002) but there were no significant differences with vigorous exercise. We found that pet owners were significantly more positive about their neighbourhood than non-owners on 8/9 questions, while dog owners were (significantly) even more positive than owners of other pets on 8/9 questions. Associations with sleep were mixed, although dog owners had less trouble falling asleep than non-dog owners, with borderline statistical significance.
Conclusion: Dog owners feel more positive about their neighbourhood, do more exercise, and fall asleep more easily than non-dog owners. These results suggest that dog owners could be more likely to exercise by walking their dogs and therefore may be more familiar and positive about the area in which they walk their dog
Postdigital Dialogue
This article is a multi-authored experimental postdigital dialogue about postdigital dialogue. Fourteen authors were invited to produce their sections, followed by two author-reviewers who examined the article as a whole. Authors were invited to reflect on Petar Jandric’s book Learning in the age of digital reason (2017) or to produce completely new insights. The article also contains a summary of book symposium on Learning in the age of digital reason held at the 2017 American Educational Research Conference (AERA). The authors are tentatively confident that this article produces more knowledge than the arithmetic sum of its constituent parts. However, they are also very aware of its limits and insist that their conclusions are not consensual or homogenous. As traditional forms of research increasingly fail to describe our current reality, they present this article as an experiment and a possible starting point for developing new dialogical research approaches fit for our postdigital reality
Discovery of a nanodiamond-rich layer in the Greenland ice sheet
We report the discovery in the Greenland ice sheet of a discrete layer of free nanodiamonds (NDs) in very high abundances, implying most likely either an unprecedented influx of extraterrestrial (ET) material or a cosmic impact event that occurred after the last glacial episode. From that layer, we extracted n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5!106 times background levels in adjacent younger and older ice. The NDs in the concentrated layer are rounded, suggesting they most likely formed during a cosmic impact through some process similar to carbon-vapor deposition or high-explosive detonation. This morphology has not been reported previously in cosmic material, but has been observed in terrestrial impact material. This is the first highly enriched, discrete layer of NDs observed in glacial ice anywhere, and its presence indicates that ice caps are important archives of ET events of varying magnitudes. Using a preliminary ice chronology based on oxygen isotopes and dust stratigraphy, the ND-rich layer appears to be coeval with ND abundance peaks reported at numerous North American sites in a sedimentary layer, the Younger Dryas boundary layer (YDB), dating to 12.9 0.1 ka. However, more investigation is needed to confirm this association
Home medicines reviews following acute coronary syndrome: study protocol for a randomized controlled trial
Background: Despite continual improvements in the management of acute coronary syndromes, adherence to guideline-based medications remains suboptimal. We aim to improve adherence with guideline-based therapy following acute coronary syndrome using an existing service that is provided by specifically trained pharmacists, called a Home Medicines Review. We have made two minor adjustments to target the focus of the existing service including an acute coronary syndrome specific referral letter and a training package for the pharmacists providing the service.Methods/Design: We will be conducting a randomized controlled trial to compare the directed home medicines review service to usual care following acute coronary syndromes. All patients aged 18 to 80 years and with a working diagnosis of acute coronary syndrome, who are admitted to two public, acute care hospitals, will be screened for enrolment into the trial. Exclusion criteria will include: not being discharged home, documented cognitive decline, non-Medicare eligibility, and presence of a terminal malignancy. Randomization concealment and sequence generation will occur through a centrally-monitored computer program. Patients randomized to the control group will receive usual post-discharge care. Patients randomized to receive the intervention will be offered usual post-discharge care and a directed home medicines review at two months post-discharge. The study endpoints will be six and twelve months post-discharge. The primary outcome will be the proportion of patients who are adherent to a complete, guideline-based medication regimen. Secondary outcomes will include hospital readmission rates, length of hospital stays, changes in quality of life, smoking cessation rates, cardiac rehabilitation completion rates, and mortality.Discussion: As the trial is closely based on an existing service, any improvements observed should be highly translatable into regular practice. Possible limitations to the success of the trial intervention include general practitioner approval of the intervention, general practitioner acceptance of pharmacists' recommendations, and pharmacists' ability to make appropriate recommendations. A detailed monitoring process will detect any barriers to the success of the trial. Given that poor medication persistence following acute coronary syndrome is a worldwide problem, the findings of our study may have international implications for the care of this patient group.Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12611000452998. © 2012 Bernal et al; licensee BioMed Central Ltd
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Identifying ancient water availability through phytolith analysis: An experimental approach.
Water management was critical to the development of complex societies but such systems are often difficult, if not impossible, to recognise in the archaeological record, particularly in prehistoric communities when water management began. This is because early irrigation systems are likely to have been ephemeral and as such would no longer be visible in the archaeological record. We conducted a three year crop growing experiment in Jordan to test the hypothesis that phytoliths (opaline silica bodies formed in plants) can be used to detect the level of past water availability and hence be used as a source of information for inferring past water management. Over a three year period we grew native land races of six-row barley (Hordeum vulgare) and durum wheat (Triticum durum) at three crop growing stations in Jordan with the crops being subjected to different irrigation regimes. Seeds were sown in the autumn and the crops harvested in the spring. The plants were then exported to the University of Reading for phytolith processing. Our results show that while there were unknown factors that influenced phytolith production between years, at the higher levels, the ratio of ‘fixed’ form phytoliths (those formed as a result of genetically determined Silicon uptake) to ‘sensitive’ form phytoliths (those whose Silicon uptake is environmentally controlled) can be used to assess past water availability. Our study is the first large scale experimental project to test this method and take into account multiple variables that can affect phytolith production such as soil composition and chemistry, location, climate and evapotranspiration rates. Results from the cereals grown at two of the crop growing stations, Deir ‘Alla and Ramtha, which received between 100 millimetres and 250 millimetres rainfall per annum, demonstrate that if the ratio of fixed to sensitive phytolith forms is >1, the level of past water availability can be predicted with 80% confidence. Results from the crops grown at the other growing station, Kherbet as-Samra, which received less than 100 millimetres of rainfall per year show that if the ratio of fixed to sensitive forms is >0.5, the level of past water availability can be predicted with 99% confidence. This demonstrates that phytolith analysis can be used as a method to identify past water availability
The Influence of Dormitory Architecture On Resident Behavior
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66943/2/10.1177_001391657300500402.pd
The Role of Recombination for the Coevolutionary Dynamics of HIV and the Immune Response
The evolutionary implications of recombination in HIV remain not fully understood. A plausible effect could be an enhancement of immune escape from cytotoxic T lymphocytes (CTLs). In order to test this hypothesis, we constructed a population dynamic model of immune escape in HIV and examined the viral-immune dynamics with and without recombination. Our model shows that recombination (i) increases the genetic diversity of the viral population, (ii) accelerates the emergence of escape mutations with and without compensatory mutations, and (iii) accelerates the acquisition of immune escape mutations in the early stage of viral infection. We see a particularly strong impact of recombination in systems with broad, non-immunodominant CTL responses. Overall, our study argues for the importance of recombination in HIV in allowing the virus to adapt to changing selective pressures as imposed by the immune system and shows that the effect of recombination depends on the immunodominance pattern of effector T cell responses
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