GPS and PSI integration for monitoring urban land motion

Urban ground motion due to natural or man-made geological processes is an issue of major importance for local authorities, property developers, planners and buyers. Increased knowledge of this phenomena would benefit all involved but the measurement techniques in common use have either spatial or temporal inadequacies. A technique known as Persistent Scatterer Interferometry (PSI) has been developed which can map ground motion to high precision over large areas with a temporal scale measured in years. PSI takes advantage of the high number of Synthetic Aperture Radar (SAR) images available to mitigate the atmospheric effects that inhibit standard Interferometric SAR (InSAR) techniques. This however involves assumptions about the nature of atmospheric variability, such as its randomness over time, or its spatial extent. In addition, little is known about the Persistent Scatterers (PS) themselves and PSI is only able to provide results relative to a reference PS. The reference PS point is often arbitrarily chosen and may itself be in an area undergoing ground motion, thus adding a degree of ambiguity to any relatively derived motion. The purpose of this work is to investigate possible solutions to these shortfalls and quantify any improvements made. A corner reflector network is established in the Nottingham area of the UK. A data archive is collated over three years containing Global Positioning System (GPS) data at the corner reflector sites, data from surrounding Continuous GPS (CGPS) sites and levelling data. Due to conflicts with the European Space Agency (ESA) Environmental Satellite (ENVISAT), there were insufficient SAR images to com- pute a fully integrated corner reflector PSI study. Instead, the project focussed on atmospheric correction of PSI results using absolute ZWD estimates. Zenith Wet Delay (ZWD) estimates are derived from a Precise Point Positioning (PPP) GPS processing method which does not rely on a network of ground stations and therefore produces absolute ZWD estimates which are less prone to biases and noise. These are interpolated across a PSI study area and used to mitigate the long wavelength effects of atmopheric water vapour in the PSI differential interferograms. The corrected PSI results are then compared to uncorrected results, GPS derived motion and levelling data. Results between the ZWD corrected PSI study and the uncorrected study show statistical improvements in some areas and reductions in others. Correlation factors between double-differenced levelling observations and double-differenced PSI results improve from 0.67 to 0.81. PSI deformation rates also show improvement when compared to GPS deformation rates, although some results do not satisfy statistical tests

The associations between self-reported depression, self-reported chronic inflammatory conditions and cognitive abilities in UK Biobank

Background: Depression and chronic inflammatory medical conditions have been linked to impaired cognitive ability. However despite frequent comorbidity, their combined association with cognitive ability has rarely been examined. Methods: This study examined associations between self-reported depression and chronic inflammatory diseases and their interaction with cognitive performance in 456,748 participants of the UK Biobank, adjusting for sociodemographic and lifestyle factors. Numbers with available data ranged from 94,899 to 453,208 depending on the cognitive test. Results: Self-reported depression was associated with poorer performance compared to controls in several cognitive tests (fully adjusted models, reaction time: B = 6.08, 95% CI = 5.09, 7.07; pairs matching: incidence rate ratio = 1.02, 95% CI = 1.02, 1.03; Trail Making Test B: B = 1.37, 95% CI = 0.88, 1.87; Digit Symbol Substitution Test (DSST): B = −0.35, 95% CI = −0.44, −0.27). Self-reported chronic inflammatory conditions were associated with slower reaction time (B = 3.79, 95% CI = 2.81, 4.78) and lower DSST scores (B = −0.21, 95% CI = −0.30, −0.13). No interaction effects were observed. Discussion: In this large, population-based study we provide evidence of lower cognitive performance in both depression and a comprehensive category of chronic inflammatory conditions. Results are consistent with additive effects of both types of disorder on cognitive ability. Clinicians should be aware of such effects, particularly as cognitive impairment is linked to poorer disease outcomes and quality of life

Survey and online discussion groups to develop a patient-rated outcome measure on acceptability of treatment response in vitiligo

BackgroundVitiligo is a chronic depigmenting skin disorder which affects around 0.5-1% of the world’s population. The outcome measures used most commonly in trials to judge treatment success focus on repigmentation. Patient-reported outcome measures of treatment success are rarely used, although recommendations have been made for their inclusion in vitiligo trials. This study aimed to evaluate the face validity of a new patient-reported outcome measure of treatment response, for use in future trials and clinical practice. MethodAn online survey to gather initial views on what constitutes treatment success for people with vitiligo or their parents/carers, followed by online discussion groups with patients to reach consensus on what constitutes treatment success for individuals with vitiligo, and how this can be assessed in the context of trials. Participants were recruited from an existing database of vitiligo patients and through posts on the social network sites Facebook and Twitter. ResultsA total of 202 survey responses were received, of which 37 were excluded and 165 analysed. Three main themes emerged as important in assessing treatment response: a) the match between vitiligo and normal skin (how well it blends in); b) how noticeable the vitiligo is and c) a reduction in the size of the white patches. The majority of respondents said they would consider 80% or more repigmentation to be a worthwhile treatment response after 9 months of treatment. Three online discussion groups involving 12 participants led to consensus that treatment success is best measured by asking patients how noticeable their vitiligo is after treatment. This was judged to be best answered using a 5-point Likert scale, on which a score of 4 or 5 represents treatment success. ConclusionsThis study represents the first step in developing a patient reported measure of treatment success in vitiligo trials. Further work is now needed to assess its construct validity and responsiveness to change.<br/

Amplification of simian retroviral sequences from human recipients of baboon liver transplants

Investigations into the use of baboons as organ donors for human transplant recipients, a procedure called xenotransplantation, have raised the specter of transmitting baboon viruses to humans and possibly establishing new human infectious diseases. Retrospective analysis of tissues from two human transplant recipients with end-stage hepatic disease who died 70 and 27 days after the transplantation of baboon livers revealed the presence of two simian retroviruses of baboon origin, simian foamy virus (SFV) and baboon endogenous virus (BaEV), in multiple tissue compartments. The presence of baboon mitochondrial DNA was also detected in these same tissues, suggesting that xenogeneic 'passenger leukocytes' harboring latent or active viral infections had migrated from the xenografts to distant sites within the human recipients. The persistence of SFV and BaEV in human recipients throughout the posttransplant period underscores the potential infectious risks associated with xenotransplantation

Using the Vitiligo Noticeability Scale in clinical trials: construct validity, interpretability, reliability and acceptability

Background: Validated outcome measures are needed for vitiligo trials. Objectives: To assess construct validity, interpretability, reliability and acceptability of the Vitiligo Noticeability Scale (VNS). Methods: We used images of vitiligo before and after treatment, plus outcome data, from the HI-Light Vitiligo trial. We compared outcome assessments made by trial participants with assessments of images by clinicians and people with vitiligo who were not trial participants [Patient and Public Involvement (PPI) panel]. Hypothesis testing assessed psychometric properties of the VNS, with κ statistics to assess agreement between outcomes. Three focus groups and two online discussion groups provided insight into the use of VNS by people with vitiligo. Results: Our hypothesis of a positive association between VNS and participant-reported global treatment success was supported for trial participants (κ = 0·41 if VNS success was defined as ≥ 4; κ = 0·71 if VNS success was defined as ≥ 3), but not for the blinded PPI panel (κ = 0·28). As hypothesized, the association with participant-reported global success was higher for VNS (κ = 0·41) than for clinician-reported percentage repigmentation (κ = 0·17). Seventy-five per cent of trial participants valued a VNS of 3 (partial response) as a treatment success. Test–retest reliability was good: κ = 0·69 (95% confidence interval 0·63–0·74). Age and skin phototype did not influence interpretation of the VNS scores. To people with vitiligo, the VNS is an acceptable and meaningful patient-reported outcome measure. Conclusions: Trial participants may assess their vitiligo differently compared with blinded assessors. A VNS score of 3 may be more highly valued by people undergoing vitiligo treatment than was previously thought. What is already known about this topic? Vitiligo is a common condition, and can have a considerable psychological impact. A Vitiligo Core Outcome Set is being developed, to enable the results of vitiligo trials to be compared and combined more easily. The Vitiligo Noticeability Scale (VNS) is a patient-reported outcome measure (PROM) developed in partnership with people with vitiligo; initial validation studies have been promising. What does this study add? The VNS shows good construct validity, reliability and acceptability; it can be used in all ages and skin phototypes. All five levels of the VNS scale should be reported for transparency, to aid interpretation of trial findings, and to facilitate meta-analysis in systematic reviews. VNS assessments made by trial participants and independent observers are likely to be qualitatively different, making blinded assessment of VNS by independent observers difficult to interpret. Blinding of participants to trial interventions is recommended whenever possible. What are the clinical implications of the work? The VNS can be used as a PROM to assess the cosmetic acceptability of repigmentation at individual patches of vitiligo. A VNS score of 3 or more is likely to be valued by patients as a treatment success

Time-lapse imaging of CO2 migration within near-surface sediments during a controlled sub-seabed release experiment

The ability to detect and monitor any escape of carbon dioxide (CO2) from sub-seafloor CO2 storage reservoirs is essential for public acceptance of carbon capture and storage (CCS) as a climate change mitigation strategy. Here, we use repeated high-resolution seismic reflection surveys acquired using a chirp profiler mounted on an autonomous underwater vehicle (AUV), to image CO2 gas released into shallow sub-surface sediments above a potential CCS storage site at 120 m water depth in the North Sea. Observations of temporal changes in seismic reflectivity, attenuation, unit thickness and the bulk permeability of sediment were used to develop a four-stage model of the evolution of gas migration in shallow marine sediments: Proto-migration, Immature Migration, Mature Migration, and Pathway Closure. Bubble flow was initially enabled through the propagation of stable fractures but, over time, transitioned to dynamic fractures with an associated step change in permeability. Once the gas injection rate exceeded the rate at which gas could escape the coarser sediments overlying the injection point, gas began to pool along a grain size boundary. This enhanced understanding of the migration of free gas in near-surface sediments will help improve methods of detection and quantification of gas in subsurface marine sediments

Deranged sodium to sudden death

In February 2014, a group of scientists convened as part of the University of California Davis Cardiovascular Symposium to bring together experimental and mathematical modelling perspectives and discuss points of consensus and controversy on the topic of sodium in the heart. This paper summarizes the topics of presentation and discussion from the symposium, with a focus on the role of aberrant sodium channels and abnormal sodium homeostasis in cardiac arrhythmias and pharmacotherapy from the subcellular scale to the whole heart. Two following papers focus on Na⁺ channel structure, function and regulation, and Na⁺/Ca²⁺ exchange and Na⁺/K⁺ ATPase. The UC Davis Cardiovascular Symposium is a biannual event that aims to bring together leading experts in subfields of cardiovascular biomedicine to focus on topics of importance to the field. The focus on Na⁺ in the 2014 symposium stemmed from the multitude of recent studies that point to the importance of maintaining Na⁺ homeostasis in the heart, as disruption of homeostatic processes are increasingly identified in cardiac disease states. Understanding how disruption in cardiac Na⁺-based processes leads to derangement in multiple cardiac components at the level of the cell and to then connect these perturbations to emergent behaviour in the heart to cause disease is a critical area of research. The ubiquity of disruption of Na⁺ channels and Na⁺ homeostasis in cardiac disorders of excitability and mechanics emphasizes the importance of a fundamental understanding of the associated mechanisms and disease processes to ultimately reveal new targets for human therapy.Centro de Investigaciones Cardiovasculare

Home-based narrowband UVB, topical corticosteroid or combination for children and adults with vitiligo: HI-Light Vitiligo three-arm RCT

BACKGROUND: Systematic reviews suggest that narrowband ultraviolet B light combined with treatments such as topical corticosteroids may be more effective than monotherapy for vitiligo. OBJECTIVE: To explore the clinical effectiveness and cost-effectiveness of topical corticosteroid monotherapy compared with (1) hand-held narrowband ultraviolet B light monotherapy and (2) hand-held narrowband ultraviolet B light/topical corticosteroid combination treatment for localised vitiligo. DESIGN: Pragmatic, three-arm, randomised controlled trial with 9 months of treatment and a 12-month follow-up. SETTING: Sixteen UK hospitals - participants were recruited from primary and secondary care and the community. PARTICIPANTS: Adults and children (aged ≥ 5 years) with active non-segmental vitiligo affecting ≤ 10% of their body area. INTERVENTIONS: Topical corticosteroids [mometasone furoate 0.1% (Elocon®, Merck Sharp & Dohme Corp., Merck & Co., Inc., Whitehouse Station, NJ, USA) plus dummy narrowband ultraviolet B light]; narrowband ultraviolet B light (narrowband ultraviolet B light plus placebo topical corticosteroids); or combination (topical corticosteroids plus narrowband ultraviolet B light). Topical corticosteroids were applied once daily on alternate weeks and narrowband ultraviolet B light was administered every other day in escalating doses, with a dose adjustment for erythema. All treatments were home based. MAIN OUTCOME MEASURES: The primary outcome was self-assessed treatment success for a chosen target patch after 9 months of treatment ('a lot less noticeable' or 'no longer noticeable' on the Vitiligo Noticeability Scale). Secondary outcomes included blinded assessment of primary outcome and percentage repigmentation, onset and maintenance of treatment response, quality of life, side effects, treatment burden and cost-effectiveness (cost per additional successful treatment). RESULTS: In total, 517 participants were randomised (adults, n = 398; and children, n =  119; 52% male; 57% paler skin types I-III, 43% darker skin types IV-VI). At the end of 9 months of treatment, 370 (72%) participants provided primary outcome data. The median percentage of narrowband ultraviolet B light treatment-days (actual/allocated) was 81% for topical corticosteroids, 77% for narrowband ultraviolet B light and 74% for combination groups; and for ointment was 79% for topical corticosteroids, 83% for narrowband ultraviolet B light and 77% for combination. Target patch location was head and neck (31%), hands and feet (32%), and rest of the body (37%). Target patch treatment 'success' was 20 out of 119 (17%) for topical corticosteroids, 27 out of 123 (22%) for narrowband ultraviolet B light and 34 out of 128 (27%) for combination. Combination treatment was superior to topical corticosteroids (adjusted risk difference 10.9%, 95% confidence interval 1.0% to 20.9%; p = 0.032; number needed to treat = 10). Narrowband ultraviolet B light was not superior to topical corticosteroids (adjusted risk difference 5.2%, 95% confidence interval -4.4% to 14.9%; p = 0.290; number needed to treat = 19). The secondary outcomes supported the primary analysis. Quality of life did not differ between the groups. Participants who adhered to the interventions for > 75% of the expected treatment protocol were more likely to achieve treatment success. Over 40% of participants had lost treatment response after 1 year with no treatment. Grade 3 or 4 erythema was experienced by 62 participants (12%) (three of whom were using the dummy) and transient skin thinning by 13 participants (2.5%) (two of whom were using the placebo). We observed no serious adverse treatment effects. For combination treatment compared with topical corticosteroids, the unadjusted incremental cost-effectiveness ratio was £2328.56 (adjusted £1932) per additional successful treatment (from an NHS perspective). LIMITATIONS: Relatively high loss to follow-up limits the interpretation of the trial findings, especially during the post-intervention follow-up phase. CONCLUSION: Hand-held narrowband ultraviolet B light plus topical corticosteroid combination treatment is superior to topical corticosteroids alone for treatment of localised vitiligo. Combination treatment was relatively safe and well tolerated, but was effective in around one-quarter of participants only. Whether or not combination treatment is cost-effective depends on how much decision-makers are willing to pay for the benefits observed. FUTURE WORK: Development and testing of new vitiligo treatments with a greater treatment response and longer-lasting effects are needed. TRIAL REGISTRATION: Current Controlled Trials ISRCTN17160087. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 64. See the NIHR Journals Library website for further project information