CATASTROPHIC FLANK COLLAPSE ON TA’U ISLAND AND SUBSEQUENT TSUNAMI: HAS THIS OCCURRED DURING THE LAST 170 YEARS?

Ta’u, the easternmost inhabited island in the Samoan Islands archipelago, exhibits a series of down-faulted benches on its southern flank, believed to be the remnant of ~30 km3 catastrophic collapse. A historical map of Ta’u charted in 1839 during the United States Exploring Expedition, which did not show the benches, suggests that the event occurred less than 170 years ago. A collapse event of this magnitude would have generated a locally devastating tsunami, with possible impacts experienced at the regional level. However, no written or oral records of such an event exist. A number of key questions thus emerge, and formed the basis for this study. Did this event actually happen within the last 170 years, and if so, how and why could it have gone unnoticed? Or, is the event much older than the impression obtained from the literature? The catastrophic flank collapse was modeled using 100 m contour-resolution bathymetry data of the Ta’u region, coupled with rational assumptions made on the geometry of the failed mass. This enabled numerical landslide- tsunami simulation in the Cornell Multigrid Coupled Tsunami Model (COMCOT). The results indicate that if an event of this magnitude occurred in the last 170 years, it could not have gone unnoticed by local inhabitants. It thus seems likely that the initial survey conducted during the Exploring Expedition was inaccurate. Nevertheless, the well-preserved nature of the benches indicates collapse relatively recently and raises the possibility of future collapse

Promotion of faster weight gain in infants born small for gestational age - Is there an adverse effect on later blood pressure?

Background - Being born small for gestational age is associated with later risk factors for cardiovascular disease, such as high blood pressure. Promotion of postnatal growth has been proposed to ameliorate these effects. There is evidence in animals and infants born prematurely, however, that promotion of growth by increased postnatal nutrition increases rather than decreases later cardiovascular risk. We report the long-term impact of growth promotion in term infants born small for gestational age ( birth weight < 10th percentile).Methods and Results - Blood pressure was measured at 6 to 8 years in 153 of 299 ( 51%) of a cohort of children born small for gestational age and randomly assigned at birth to receive either a standard or a nutrient-enriched formula. The enriched formula contained 28% more protein than standard formula and promoted weight gain. Diastolic and mean ( but not systolic) blood pressure was significantly lower in children assigned to standard compared with nutrient-enriched formula ( unadjusted mean difference for diastolic blood pressure, - 3.2 mm Hg; 95% CI, - 5.8 to - 0.5; P = 0.02) independent of potential confounding factors ( adjusted difference, - 3.5 mm Hg; P = 0.01). In observational analyses, faster weight gain in infancy was associated with higher later blood pressure.Conclusions - In the present randomized study targeted to investigate the effect of early nutrition on long-term cardiovascular health, we found that a nutrient-enriched diet increased later blood pressure. These findings support an adverse effect of relative "overnutrition" in infancy on long-term cardiovascular disease risk, have implications for the early origins of cardiovascular disease hypothesis, and do not support the promotion of faster weight gain in infants born small for gestational age

Nano-scale reservoir computing

This work describes preliminary steps towards nano-scale reservoir computing using quantum dots. Our research has focused on the development of an accumulator-based sensing system that reacts to changes in the environment, as well as the development of a software simulation. The investigated systems generate nonlinear responses to inputs that make them suitable for a physical implementation of a neural network. This development will enable miniaturisation of the neurons to the molecular level, leading to a range of applications including monitoring of changes in materials or structures. The system is based around the optical properties of quantum dots. The paper will report on experimental work on systems using Cadmium Selenide (CdSe) quantum dots and on the various methods to render the systems sensitive to pH, redox potential or specific ion concentration. Once the quantum dot-based systems are rendered sensitive to these triggers they can provide a distributed array that can monitor and transmit information on changes within the material.Comment: 8 pages, 9 figures, accepted for publication in Nano Communication Networks, http://www.journals.elsevier.com/nano-communication-networks/. An earlier version was presented at the 3rd IEEE International Workshop on Molecular and Nanoscale Communications (IEEE MoNaCom 2013

Imposed faster and slower walking speeds influence gait stability differently in Parkinson fallers

Objective To evaluate the effect of imposed faster and slower walking speeds on postural stability in people with Parkinson disease (PD). Design Cross-sectional cohort study. Setting General community. Participants Patients with PD (n=84; 51 with a falls history; 33 without) and age-matched controls (n=82) were invited to participate via neurology clinics and preexisting databases. Of those contacted, 99 did not respond (PD=36; controls=63) and 27 were not interested (PD=18; controls=9). After screening, a further 10 patients were excluded; 5 had deep brain stimulation surgery and 5 could not accommodate to the treadmill. The remaining patients (N=30) completed all assessments and were subdivided into PD fallers (n=10), PD nonfallers (n=10), and age-matched controls (n=10) based on falls history. Interventions Not applicable. Main Outcome Measures Three-dimensional accelerometers assessed head and trunk accelerations and allowed calculation of harmonic ratios and root mean square (RMS) accelerations to assess segment control and movement amplitude. Results Symptom severity, balance confidence, and medical history were established before participants walked on a treadmill at 70%, 100%, and 130% of their preferred speed. Head and trunk control was lower for PD fallers than PD nonfallers and older adults. Significant interactions indicated head and trunk control increased with speed for PD nonfallers and older adults, but did not improve at faster speeds for PD fallers. Vertical head and trunk accelerations increased with walking speed for PD nonfallers and older adults, while the PD fallers demonstrated greater anteroposterior RMS accelerations compared with both other groups. Conclusions The results suggest that improved gait dynamics do not necessarily represent improved walking stability, and this must be respected when rehabilitating gait in patients with PD

Is arterial stiffening associated with adiposity, severity of obesity and other contemporary cardiometabolic markers in a community sample of adolescents with obesity in the UK?

BACKGROUND: Cardiovascular disease (CVD) prediction is problematic within groups of obese adolescents as measures such as adiposity and metabolic markers lack validation. Pulse wave velocity (PWV), a proxy for arterial stiffening, is a potential way to contemporaneously capture adolescents at greater risk of CVD. OBJECTIVES: To investigate associations between PWV and 1) adiposity and 2) other conventional metabolic factors in a community sample of (>95th centile body mass index (BMI)). DESIGN AND SETTING: Cross-sectional measurement and analysis in a hospital-based research centre drawn from a community sample of adolescents recruited to an obesity intervention at baseline. PATIENTS: 174 adolescents (12-19 years) with obesity (>95th centile BMI). 37% were male, while 66 (38%) were white, 53 (30%) black, 36 (21%) South Asian, 19 (11%) mixed/other. Participants with endocrine, genetic causes of obesity and chronic medical conditions (excluding asthma) were excluded. MEASURES: BMI z-score (zBMI), waist z-score, fat mass index (FMI: measured using bioimpedance), sagittal abdominal dimension (SAD), cardiometabolic blood tests and resting blood pressure (BP) were collected. Carotid-radial PWV was measured by a single operator. RESULTS: PWV was associated with age but not pubertal stage. PWV was positively associated with adiposity (zBMI: coefficient 0.44 (95% CI 0.08 to 0.79); FMI: coefficient 0.05 (95% CI 0.00 to 0.10); waist z-score: coefficient 0.27 (95% CI 0.00 to 0.53); SAD: coefficient 0.06 (95% CI: 0.00 to 0.12)). There was no association between PWV and BP, and few associations with cardiometabolic bloods. Associations between PWV and adiposity measures were robust to adjustment in multivariable models except for SAD. Participants with zBMI >2.5 SD and >3.5 SD had greater average PWV but overlap between groups was large. CONCLUSIONS: In our sample, increasing adiposity was positively associated with arterial stiffness, however partitioning by severity was not reliable. Lack of associations between BP, cardiometabolic bloods and arterial stiffness questions the reliability of these factors for predicting CVD risk in adolescents with obesity

Rethinking human responses to sea-level rise : the Mesolithic occupation of the Channel Islands

This work provides new insights into human responses to and perceptions of sea-level rise at a time when the landscapes of north-west Europe were radically changing. These issues are investigated through a case study focused on the Channel Islands. We report on the excavation of two sites, Canal du Squez in Jersey and Lihou (GU582) in Guernsey, and the study of museum collections across the Channel Islands. We argue that people were drawn to this area as a result of the dynamic environmental processes occurring and the opportunities these created. The evidence suggests that the area was a particular focus during the Middle Mesolithic, when Guernsey and Alderney were already islands and while Jersey was a peninsula of northern France. Insularisation does not appear to have created a barrier to occupation during either the Middle or Final Mesolithic, indicating the appearance of lifeways increasingly focused on maritime voyaging and marine resources from the second half of the 9th millennium BC onwards.PostprintPeer reviewe

A combined geochemical and hydrological approach for understanding macronutrient sources

This study employed complementary geochemical techniques and distributed hydrological modelling to investigate multiple sources of catchment macronutrients and characterise their changes in contrasting storm and baseflow conditions. This approach was demonstrated for the Beult catchment in the county of Kent (England), a designated Site of Special Scientific Interest (SSSI) indentified as failing to meet water quality standards for key nutrients under the Water Framework Directive. Significant changes in nutrient stoichiometry and bioavailability are observed for surface waters under contrasting flow regimes. Soluble reactive phosphorus (SRP) concentrations are approximately twice as high during baseflow compared to high flow, while the inverse is true for particulate, colloidal and dissolved hydrolysable phosphorus, dissolved organic carbon and nitrate. Nitrogen (N):phosphorus (P) ratios are lower during baseflow for most surface waters impacted by diffuse sources of pollution. Fluorescence indices of dissolved organic matter (DOM) show that waste water inputs may be locally important sources of more complex low molecular weight DOM, particularly during baseflow. Nitrate N and O isotope signatures, combined with other dissolved chemical tracers, confirm the dominance of wastewater N inputs at sites downsteam of sewerage treatment works during baseflow, with a shift towards the soil N pool in surface waters across the catchment during high flow. Distributed hydrological modelling using the Grid-to-Grid model reveal areas with the greatest runoff also export higher N and P concentrations, and hence deliver a greater flux of macronutrients, while forested areas with low nutrient concentrations reduce runoff and nutrient fluxes. During periods of high runoff, nested sampling indicates that nutrient fluxes scale with catchment area. This combined approach enables a more thorough assessment of the macronutrient sources and dynamics, better informing management options in nutrient impacted catchments

After the RCT: who comes to a family-based intervention for childhood overweight or obesity when it is implemented at scale in the community?

Background: When implemented at scale, the impact on health and health inequalities of public health interventions depends on who receives them in addition to intervention effectiveness. Methods: The MEND 7–13 (Mind, Exercise, Nutrition…Do it!) programme is a family-based weight management intervention for childhood overweight and obesity implemented at scale in the community. We compare the characteristics of children referred to the MEND programme (N=18 289 referred to 1940 programmes) with those of the population eligible for the intervention, and assess what predicts completion of the intervention. Results: Compared to the MEND-eligible population, proportionally more children who started MEND were: obese rather than overweight excluding obese; girls; Asian; from families with a lone parent; living in less favourable socioeconomic circumstances; and living in urban rather than rural or suburban areas. Having started the programme, children were relatively less likely to complete it if they: reported ‘abnormal’ compared to ‘normal’ levels of psychological distress; were boys; were from lone parent families; lived in less favourable socioeconomic circumstances; and had participated in a relatively large MEND programme group; or where managers had run more programmes. Conclusions: The provision and/or uptake of MEND did not appear to compromise and, if anything, promoted participation of those from disadvantaged circumstances and ethnic minority groups. However, this tendency was diminished because programme completion was less likely for those living in less favourable socioeconomic circumstances. Further research should explore how completion rates of this intervention could be improved for particular groups