The response of Hagafellsjökull Vestari glacier, Iceland, to future climate scenarios computed with a dynamic glacier flowline model coupled to a degree-day mass balance model

A dynamic glacier flowline model is coupled to a degree-day mass balance model with the purpose of modelling the response of Hagafellsjökull vestari glacier to future climate change scenarios. The degree-day mass balance model is calibrated using mass balance measurements for the period 1997-2007. The temperature and precipitation input for the calibration is provided by a combination of ERA-40 reanalysis data and local weather station records. The calibrated model shows good agreement with the measured mass balances (r2 = 0.95, RMSE = 0.68 m w.e.). The flowline model is then calibrated against the 2007 surface profile extracted from a DEM constructed from LiDAR data. During calibration the model is run from 1997 to 2007 with the mass balance input provided by the calibrated degree-day model. A number of changes had to be made to the model in order to achieve a good fit with the reference profile. These included a parameterisation of the basal mechanisms of movement (i.e. sliding and deformation of the bed) which was forced by the calculation of water flux at the base; and the introduction of a uniform basal melt rate. The calibrated model calculates the 2007 ice surface profile with an RMSE of 4.41 m. The need to introduce a basal melt rate of 0.8 m yr-1 suggests the presence under the glacier of a significant source of geothermal energy. A range of climate scenarios are imposed on the finalised model to predict the glacier’s behaviour between 2007 and 2109. In the ‘worst-case’ scenario the glacier will lose almost 80% of the 2007 ice volume over the next century. If there is no future climate change relative to the 1978-2007 30-year averages for temperature and precipitation, by 2109 the glacier will lose 30% of the 2007 ice volume and the glacier front will retreat by just over 5 km from its 2007 position

Flow quality studies of the NASA Lewis Research Center 8- by 6-foot supersonic/9- by 15-foot low speed wind tunnel

A series of studies were conducted to determine the existing flow quality in the NASA Lewis 8 by 6 Foot Supersonic/9 by 15 Foot Low speed Wind Tunnel. The information gathered from these studies was used to determine the types and designs of flow manipulators which can be installed to improve overall tunnel flow quality and efficiency. Such manipulators include honeycomb flow straighteners, turbulence reduction screens, corner turning vanes, and acoustic treatments. The types of measurements, instrumentation, and results obtained from experiments conducted at several locations throughout the tunnel loop are described

Flow quality studies of the NASA Lewis Research Center Icing Research Tunnel diffuser

The purpose was to document the airflow characteristics in the diffuser of the NASA Lewis Research Center Icing Research Tunnel and to determine the effects of vortex generators on the flow quality in the diffuser. The results were used to determine how to improve the flow in this portion of the tunnel so that it can be more effectively used as an icing test section and such that overall tunnel efficiency can be improved. The demand for tunnel test time and the desire to test models that are too large for the test section were two of the drivers behind this diffuser study. For all vortex generator configurations tested, the flow quality was improved

QuikSCAT Satellite Comparisons with Nearshore Buoy Wind Data off the U.S. West Coast

To determine the accuracy of nearshore winds from the QuikSCAT satellite, winds from three satellite datasets (scientifically processed swath, gridded near-real-time, and gridded science datasets) were compared to those from 12 nearshore and 3 offshore U.S. West Coast buoys. Satellite observations from August 1999 to December 2000 that were within 25 km and 30 min of each buoy were used. Comparisons showed that satellite–buoy wind differences near shore were larger than those offshore. Editing the satellite data by discarding observations recorded in rain and those recorded in light winds improved the accuracy of all three datasets. After removing rain-flagged data and wind speeds less than 3 m s21, root-mean-squared differences (satellite minus buoy) for swath data, the best of the three datasets, were 1.4 m s21 and 378 based on 5741 nearshore comparisons. By removing winds less than 6 m s21, these differences were reduced to 1.3 m s21 and 268. At the three offshore buoys, the root-mean-squared differences for the swath data, with both rain and winds less than 6 m s21 removed, were 1.0 m s21 and 158 based on 1920 comparisons. Although the satellite’s scientifically processed swath data near shore do not match buoy observations as closely as those offshore, they are sufficiently accurate for many coastal studies

Could the rise in mortality rates since 2015 be explained by changes in the number of delayed discharges of NHS patients?

Background: 2015 saw the largest annual spike in mortality rates in in England in almost 50 years. We examine whether these changes in mortality rates are associated with an indicator of poor functioning of health and social care – delay in hospital discharges. Methods: ONS monthly data of death counts and mortality rates for the period August 2010- March 2016 were compared to delays in discharges from NHS England data on transfers of care for acute and non-acute patients for England. Autoregressive Integrated Moving Average (ARIMA) regression models were used in analysis. Results: We estimate that each additional day an acute admission was late being discharged was associated with an increase in 0.394 deaths (95% CIs: 0.220-0.569). For each additional acute patient delayed being discharged, we found an increase of 7.322 deaths (95% CIs: 1.754-12.890). Findings for non-acute admissions were mixed. Conclusion: The increased prevalence of patients being delayed in discharge from hospital in 2015 was associated with increases in mortality, as many as 7,322 (CIs 1,754 to 12,890) deaths in a year in England. Our study provides evidence that a lower quality of performance of the NHS and adult social care as a result of austerity may be having an adverse impact on population health

Electronic Structure of Superconducting Ba6c60

We report the results of first-principles electronic-structure calculations for superconducting Ba6C60. Unlike the A3C60 superconductors, this new compound shows strong Ba-C hybridization in the valence and conduction regions, mixed covalent/ionic bonding character, partial charge transfer, and insulating zero-gap band structure.Comment: 11 pages + 4 figures (1 appended, others on request), LaTeX with REVTE

Extensive and Intimate Association of the Cytoskeleton with Forming Silica in Diatoms: Control over Patterning on the Meso- and Micro-Scale

BACKGROUND: The diatom cell wall, called the frustule, is predominantly made out of silica, in many cases with highly ordered nano- and micro-scale features. Frustules are built intracellularly inside a special compartment, the silica deposition vesicle, or SDV. Molecules such as proteins (silaffins and silacidins) and long chain polyamines have been isolated from the silica and shown to be involved in the control of the silica polymerization. However, we are still unable to explain or reproduce in vitro the complexity of structures formed by diatoms. METHODS/PRINCIPAL FINDING: In this study, using fluorescence microscopy, scanning electron microscopy, and atomic force microscopy, we were able to compare and correlate microtubules and microfilaments with silica structure formed in diversely structured diatom species. The high degree of correlation between silica structure and actin indicates that actin is a major element in the control of the silica morphogenesis at the meso and microscale. Microtubules appear to be involved in the spatial positioning on the mesoscale and strengthening of the SDV. CONCLUSIONS/SIGNIFICANCE: These results reveal the importance of top down control over positioning of and within the SDV during diatom wall formation and open a new perspective for the study of the mechanism of frustule patterning as well as for the understanding of the control of membrane dynamics by the cytoskeleton

Blending of nanoscale and microscale in uniform large-area sculptured thin-film architectures

The combination of large thickness ($>3$ $\mu$m), large--area uniformity (75 mm diameter), high growth rate (up to 0.4 $\mu$m/min) in assemblies of complex--shaped nanowires on lithographically defined patterns has been achieved for the first time. The nanoscale and the microscale have thus been blended together in sculptured thin films with transverse architectures. SiO$_x$ ($x\approx 2$) nanowires were grown by electron--beam evaporation onto silicon substrates both with and without photoresist lines (1--D arrays) and checkerboard (2--D arrays) patterns. Atomic self--shadowing due to oblique--angle deposition enables the nanowires to grow continuously, to change direction abruptly, and to maintain constant cross--sectional diameter. The selective growth of nanowire assemblies on the top surfaces of both 1--D and 2--D arrays can be understood and predicted using simple geometrical shadowing equations.Comment: 17 pages, 9 figure

Human telomeres that contain (CTAGGG)n repeats show replication dependent instability in somatic cells and the male germline

A number of different processes that impact on telomere length dynamics have been identified but factors that affect the turnover of repeats located proximally within the telomeric DNA are poorly defined. We have identified a particular repeat type (CTAGGG) that is associated with an extraordinarily high mutation rate (20% per gamete) in the male germline. The mutation rate is affected by the length and sequence homogeneity of the (CTAGGG)n array. This level of instability was not seen with other sequence-variant repeats, including the TCAGGG repeat type that has the same composition. Telomeres carrying a (CTAGGG)n array are also highly unstable in somatic cells with the mutation process resulting in small gains or losses of repeats that also occasionally result in the deletion of the whole (CTAGGG)n array. These sequences are prone to quadruplex formation in vitro but adopt a different topology from (TTAGGG)n (see accompanying article). Interestingly, short (CTAGGG)2 oligonucleotides induce a DNA damage response (γH2AX foci) as efficiently as (TTAGGG)2 oligos in normal fibroblast cells, suggesting they recruit POT1 from the telomere. Moreover, in vitro assays show that (CTAGGG)n repeats bind POT1 more efficiently than (TTAGGG)n or (TCAGGG)n. We estimate that 7% of human telomeres contain (CTAGGG)n repeats and when present, they create additional problems that probably arise during telomere replication

Evolution of the nucleus

Under a Creative Commons license.The nucleus represents a major evolutionary transition. As a consequence of separating translation from transcription many new functions arose, which likely contributed to the remarkable success of eukaryotic cells. Here we will consider what has recently emerged on the evolutionary histories of several key aspects of nuclear biology; the nuclear pore complex, the lamina, centrosomes and evidence for prokaryotic origins of relevant players.Work in our laboratories was supported by the following agencies, and which is gratefully acknowledged; MRC and Wellcome Trust (MR/K008749/1 and 090007/Z/09/Z respectively, to MCF), C2A Junta de Andalucia to DPD and DFG GR1642/4-1 to RG.Open Access funded by Wellcome Trust.Peer Reviewe