Rehabilitation of memory following brain injury (ReMemBrIn): study protocol for a randomised controlled trial

Background Impairments of memory are commonly reported by people with traumatic brain injuries (TBI). Such deficits are persistent, debilitating, and can severely impact quality of life. Currently, many do not routinely receive follow-up appointments for residual memory problems following discharge. Methods/Design This is a multi-centre, randomised controlled trial investigating the clinical and cost-effectiveness of a group-based memory rehabilitation programme. Three hundred and twelve people with a traumatic brain injury will be randomised from four centres. Participants will be eligible if they had a traumatic brain injury more than 3 months prior to recruitment, have memory problems, are 18 to 69 years of age, are able to travel to one of our centres and attend group sessions, and are able to give informed consent. Participants will be randomised in clusters of 4 to 6 to the group rehabilitation intervention or to usual care. Intervention groups will receive 10 weekly sessions of a manualised memory rehabilitation programme, which has been developed in previous pilot studies. The intervention will include restitution strategies to retrain impaired memory functions and compensation strategies to enable participants to cope with their memory problems. All participants will receive a follow-up postal questionnaire and an assessment by a research assistant at 6 and 12 months post-randomisation. The primary outcome is the Everyday Memory Questionnaire at 6 months. Secondary outcomes include the Rivermead Behavioural Memory Test-3, General Health Questionnaire-30, health related quality of life, cost-effectiveness analysis determined by the EQ-5D and a service use questionnaire, individual goal attainment, European Brain Injury Questionnaire (patient and relative versions), and the Everyday Memory Questionnaire-relative version. The primary analysis will be based on intention to treat. A mixed-model regression analysis of the Everyday Memory Questionnaire at 6 months will be used to estimate the effect of the group memory rehabilitation programme. Discussion The study will hopefully provide robust evidence regarding the clinical and cost-effectiveness of a group-based memory rehabilitation intervention for civilians and military personnel following TBI. We discuss our decision-making regarding choice of outcome measures and control group, and the unique challenges to recruiting people with memory problems to trials

Satellite confirmation of the dominance of chlorofluorocarbons in the global stratospheric chlorine budget

OBSERVED increases in concentrations of chlorine in the stratosphere1-7 have been widely implicated in the depletion of lower-stratospheric ozone over the past two decades8-14. The present concentration of stratospheric chlorine is more than five times that expected from known natural 'background' emissions from the oceans and biomass burning15-18, and the balance has been estimated to be dominantly anthropogenic in origin, primarily due to the breakdown products of chlorofluorocarbons (CFCs)19,20. But despite the wealth of scientific data linking chlorofluorocarbon emissions to the observed chlorine increases, the political sensitivity of the ozone-depletion issue has generated a re-examination of the evidence21,22. Here we report a four-year global time series of satellite observations of hydrogen chloride (HCl) and hydrogen fluoride (HF) in the stratosphere, which shows conclusively that chlorofluorocarbon releases - rather than other anthropogenic or natural emissions - are responsible for the recent global increases in stratospheric chlorine concentrations. Moreover, all but a few per cent of observed stratospheric chlorine amounts can be accounted for by known natural and anthropogenic tropospheric emissions. Altogether, these results implicate the chlorofluorocarbon s beyond reasonable doubt as dominating ozone depletion in the lower stratosphere

Surface and Temporal Biosignatures

Recent discoveries of potentially habitable exoplanets have ignited the prospect of spectroscopic investigations of exoplanet surfaces and atmospheres for signs of life. This chapter provides an overview of potential surface and temporal exoplanet biosignatures, reviewing Earth analogues and proposed applications based on observations and models. The vegetation red-edge (VRE) remains the most well-studied surface biosignature. Extensions of the VRE, spectral "edges" produced in part by photosynthetic or nonphotosynthetic pigments, may likewise present potential evidence of life. Polarization signatures have the capacity to discriminate between biotic and abiotic "edge" features in the face of false positives from band-gap generating material. Temporal biosignatures -- modulations in measurable quantities such as gas abundances (e.g., CO2), surface features, or emission of light (e.g., fluorescence, bioluminescence) that can be directly linked to the actions of a biosphere -- are in general less well studied than surface or gaseous biosignatures. However, remote observations of Earth's biosphere nonetheless provide proofs of concept for these techniques and are reviewed here. Surface and temporal biosignatures provide complementary information to gaseous biosignatures, and while likely more challenging to observe, would contribute information inaccessible from study of the time-averaged atmospheric composition alone.Comment: 26 pages, 9 figures, review to appear in Handbook of Exoplanets. Fixed figure conversion error

Cognitive and cognitive-motor interventions affecting physical functioning: A systematic review

Background Several types of cognitive or combined cognitive-motor intervention types that might influence physical functions have been proposed in the past: training of dual-tasking abilities, and improving cognitive function through behavioral interventions or the use of computer games. The objective of this systematic review was to examine the literature regarding the use of cognitive and cognitive-motor interventions to improve physical functioning in older adults or people with neurological impairments that are similar to cognitive impairments seen in aging. The aim was to identify potentially promising methods that might be used in future intervention type studies for older adults. Methods A systematic search was conducted for the Medline/Premedline, PsycINFO, CINAHL and EMBASE databases. The search was focused on older adults over the age of 65. To increase the number of articles for review, we also included those discussing adult patients with neurological impairments due to trauma, as these cognitive impairments are similar to those seen in the aging population. The search was restricted to English, German and French language literature without any limitation of publication date or restriction by study design. Cognitive or cognitive-motor interventions were defined as dual-tasking, virtual reality exercise, cognitive exercise, or a combination of these. Results 28 articles met our inclusion criteria. Three articles used an isolated cognitive rehabilitation intervention, seven articles used a dual-task intervention and 19 applied a computerized intervention. There is evidence to suggest that cognitive or motor-cognitive methods positively affects physical functioning, such as postural control, walking abilities and general functions of the upper and lower extremities, respectively. The majority of the included studies resulted in improvements of the assessed functional outcome measures. Conclusions The current evidence on the effectiveness of cognitive or motor-cognitive interventions to improve physical functioning in older adults or people with neurological impairments is limited. The heterogeneity of the studies published so far does not allow defining the training methodology with the greatest effectiveness. This review nevertheless provides important foundational information in order to encourage further development of novel cognitive or cognitive-motor interventions, preferably with a randomized control design. Future research that aims to examine the relation between improvements in cognitive skills and the translation to better performance on selected physical tasks should explicitly take the relation between the cognitive and physical skills into account.ISSN:1471-231

Ethylene and methane in the upper water column of the subtropical Atlantic

The vertical distributions of ethylene and methane in the upper water column ofthe subtropical Atlantic were measured along a transect from Madeira to the Caribbean andcompared with temperature, salinity, oxygen, nutrients, chlorophyll-a, and dissolved organiccarbon (DOC).Methane concentrations between 41.6 and 60.7 nL L−1 were found in the upper 20 m ofthe water column giving a calculated average flux of methane into the atmosphere of 0.82 µgm−2 h−1. Methane profiles reveal several distinct maxima in the upper 500 m of the watercolumn and short-time variations which are presumably partly related to the vertical migrationof zooplankton.Ethylene concentrations in near surface waters varied in the range of 1.8 to 8.2 nL L−1.Calculated flux rates for ethylene into the atmosphere were in the range of 0.41 to 1.35 µgm−2 h−1 with a mean of 0.83 µg m−2 h−1. Maximum concentrations of up to 39.2 nL L−1were detected directly below the pycnocline in the western Atlantic. The vertical distributionsof ethylene generally showed one maximum at the pycnocline (about 100 m depth) whereelevated concentrations of chlorophyll-a, dissolved oxygen, and nutrients were also found;no ethylene was detected below 270 m depth. This suggests that ethylene release is mainlyrelated to one, probably phytoplankton associated, source, while for methane, enhanced netproduction occurs at various depth horizons. For surface waters, a simple correlation betweenethylene and chlorophyll-a or DOC concentrations could not be observed. No considerablediurnal variation was observed for the distribution and concentration of ethylene in the upperwater column

Invasive alien plants increase CH₄ emissions from a subtropical tidal estuarine wetland

Methane (CH4) is an important greenhouse gas whose emission from the largest source, wetlands is controlled by a number of environmental variables amongst which temperature, water-table, the availability of substrates and the CH4 transport properties of plants are most prominent and well characterised. Coastal wetland ecosystems are vulnerable to invasion by alien plant species which can make a significant local contribution to altering their species composition. However the effect of these changes in species composition on CH4 flux is rarely examined and so is poorly understood. Spartina alterniflora, a perennial grass native to North America, has spread rapidly along the south-east coast of China since its introduction in 1979. From 2002, this rapid invasion has extended to the tidal marshes of the Min River estuary, an area that, prior to invasion was dominated by the native plant Cyperus malaccensis. Here, we compare CH4 flux from the exotic invasive plant S. alterniflora with measurements from the aggressive native species Phragmites australis and the native species C. malaccensis following 3-years of monitoring. CH4 emissions were measured over entire tidal cycles. Soil CH4 production potentials were estimated for stands of each of above plants both in situ and in laboratory incubations. Mean annual CH4 fluxes from S. alterniflora, P. australis and C. malaccensis dominated stands over the three years were 95.7 (±18.7), 38.9 (±3.26) and 10.9 (±5.26) g m-2year-1, respectively. Our results demonstrate that recent invasion of the exotic species S. alterniflora and the increasing presence of the native plant P. australis has significantly increased CH4 emission from marshes that were previously dominated by the native species C. malaccensis. We also conclude that higher above ground biomass, higher CH4 production and more effective plant CH4 transport of S. alterniflora collectively contribute to its higher CH4 emission in the Min River estuary