1,837 research outputs found
Development of design allowable data for Celion 6000/LARC-160, graphite/polyimide composite laminates
A design allowables test program was conducted on Celion 6000/LARC-160 graphite polyimide composite to establish material performance over a 116 K (-250 F) to 589 K (600 F) temperature range. Tension, compression, in-plane shear and short beam shear properties were determined for uniaxial, quasi-isotropic and + or - 45 deg laminates. Effects of thermal aging and moisture saturation on mechanical properties were also evaluated. Celion 6000/LARC-160 graphite/polyimide can be considered an acceptable material system for structural applications to 589 K (600 F)
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UK life science company formation: patterns of growth in UK regions and the role of biotechnology incubators
This study examines the regional distribution of new life science company formation and highlights 'hotspots' of where new activity is relatively intense. The analysis indicates that there are generally two types of region, the first type contains life science clusters that were established during the early 2000s and the second type displayed little or no significant life science activity during this period. This study analyses survey data (n=580) and evidences new patterns of life science company activity within peripheral UK regions. The study shows that new life science activity is occurring away from the traditional 'Golden Triangle' of London, Cambridge and Oxford. New life science company activity can be found in peripheral regions such as the East Midlands, Yorkshire and Humberside, the North West and in Scotland. The evidence contained in this study suggests that new UK life science company activity is supported by the presence of UK biotechnology incubators. During the early 2000s there were only a handful of biotechnology incubators in the UK, by 2012 there over twenty-five. This study provides evidence to suggest that UK biotechnology incubators play an important role in supporting new life science companies. Since the early 2000s, biotechnology incubators have appeared in the same regions that display significant levels of new life science company activity. Furthermore, significant proportions of new life science companies are located in biotechnology incubators within regions that displayed little or no significant life science activity during the early 2000s. This study demonstrates that biotechnology incubators have an important role to play in supporting regional innovation systems, especially within peripheral regions in the UK
Observation of coasting beam at the HERA Proton--Ring
We present data collected with the HERA-B wire target which prove the
existence of coasting beam at the HERA proton storage ring. The coasting beam
is inherently produced by the proton machine operation and is not dominated by
target effects.Comment: 17 pages (Latex), 12 figures (Enc. Postscript
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Developing adaptive capability: the case of Nottinghamâs nascent biotechnology sector
A regionâs adaptive capability describes its ability to respond positively to changes and shocks that affect the regional economy over time and take advantage of new and emerging market opportunities from wherever they arise. Central to this idea is the manner in which historic economic strengths or capabilities can be turned to new purposes. This paper provides a case study that uses the concept of adaptive capability as a lens through which to explore the emergence of a notable bioscience based industrial cluster in a city region of the UK and the part that it played in helping to restructure the economic base of the city. The local economy of Nottingham faced major structural changes in the late 1990s. These changes saw not only the demise of what had at one time been a key industrial sector, but also the departure of two of the cityâs three principal employers, and the closure of a major research facility owned by a third. The case explores the manner in which capabilities linked to this constellation of firms were redeployed in order to take advantage of new market opportunities. The case places particular emphasis on the contribution of firms, the restructuring of industry sectors and institutional changes that occurred at this time, to the cityâs adaptive capability. In the process the case study reveals a notable example of adaptation as the local economy moved away from a previous path of regional and sectoral development, towards a new and yet related trajectory. Central to this process was the purposive re-tasking of physical assets and the mobilization of knowledge assets that were the legacy of one of the cityâs historic industrial strengths. The paper concludes with a brief consideration of the wider relevance and applicability of this model of bioscience based regional development
Enhanced relativistic-electron beam collimation using two consecutive laser pulses
The double laser pulse approach to relativistic electron beam (REB)
collimation has been investigated at the LULI-ELFIE facility. In this scheme,
the magnetic field generated by the first laser-driven REB is used to guide a
second delayed REB. We show how electron beam collimation can be controlled by
properly adjusting laser parameters. By changing the ratio of focus size and
the delay time between the two pulses we found a maximum of electron beam
collimation clearly dependent on the focal spot size ratio of the two laser
pulses and related to the magnetic field dynamics. Cu-K alpha and CTR imaging
diagnostics were implemented to evaluate the collimation effects on the
respectively low energy ( MeV) components of the
REB
On the energetics of P-P bond dissociation of sterically strained tetraamino-diphosphanes
The homolytic P-P bond fission in a series of sterically congested tetraaminodiphosphanes (R2N)(2)P-P-(NR2)(2) ({4}(2)-{9}(2), two of which were newly synthesized and fully characterized) into diaminophosphanyl radicals (R2N)(2)P-center dot (4-9) was monitored by VT EPR spectroscopy. Determination of the radical concentration from the EPR spectra permitted to calculate free dissociation energies Delta G(Diss)(295) as well as dissociation enthalpies Delta H-Diss and entropies Delta S-Diss, respectively. Large positive values of Delta G(Diss)(295) indicate that the degree of dissociation is in most cases low, and the concentration of persistent radicals - even if they are spectroscopically observable at ambient temperature - remains small. Appreciable dissociation was established only for the sterically highly congested acyclic derivative {9}(2). Analysis of the trends in experimental data in connection with DFT studies indicate that radical formation is favoured by large entropy contributions and the energetic effect of structural relaxation (geometrical distortions and conformational changes in acyclic derivatives) in the radicals, and disfavoured by attractive dispersion forces. Comparison of the energetics of formation for CC-saturated N-heterocyclic diphosphanes and the 7 pi-radical 3c indicates that the effect of energetic stabilization by pi-electron delocalization in the latter is visible, but stands back behind those of steric and entropic contributions. Evaluation of spectroscopic and computational data indicates that diaminophosphanyl radicals exhibit, in contrast to aminophosphenium cations, no strong energetic preference for a planar arrangement of the (R2N)(2)P unit.Peer reviewe
Extreme flood response to short-duration convective rainfall in South-West Germany
The 2 June 2008 flood-producing storm on the Starzel river basin in South-West Germany is examined as a prototype for organized convective systems that dominate the upper tail of the precipitation frequency distribution and are likely responsible for the flash flood peaks in Central Europe. The availability of high-resolution rainfall estimates from radar observations and a rain gauge network, together with indirect peak discharge estimates from a detailed post-event survey, provided the opportunity to study in detail the hydrometeorological and hydrological mechanisms associated with this extreme storm and the ensuing flood. Radar-derived rainfall, streamgauge data and indirect estimates of peak discharges are used along with a distributed hydrologic model to reconstruct hydrographs at multiple locations. Observations and model results are combined to examine two main questions, (i) assessment of the distribution of the runoff ratio for the 2008 flash flood and how it compares with other less severe floods; and (ii) analysis of how the spatial and temporal distribution of the extreme rainfall, and more specifically storm motion, controls the flood response. It is shown that small runoff ratios (less than 20 %) characterized the runoff response and that these values are in the range of other, less extreme, flood events. The influence of storm structure, evolution and motion on the modeled flood hydrograph is examined by using the âspatial moments of catchment rainfallâ. It is shown that downbasin storm motion (in the range of 0.7â0.9msâ1) had a noticeable impact on flood response by increasing the modeled flood peak by 13 %
The use of data in resource limited settings to improve quality of care
Quality improvement is driven by benchmarking between and within institutions over time and the collaborative improvement efforts that stem from these comparisons. Benchmarking requires systematic collection and use of standardized data. Low- and middle-income countries (LMIC) have great potential for improvements in newborn outcomes but serious obstacles to data collection, analysis, and implementation of robust improvement methodologies exist. We review the importance of data collection, internationally recommended neonatal metrics, selected methods of data collection, and reporting. The transformation from data collection to data use is illustrated by several select data system examples from LMIC. Key features include aims and measures important to neonatal team members, co-development with local providers, immediate access to data for review, and multidisciplinary team involvement. The future of neonatal care, use of data, and the trajectory to reach global neonatal improvement targets in resource-limited settings will be dependent on initiatives led by LMIC clinicians and experts
A physical model describing the interaction of nuclear transport receptors with FG nucleoporin domain assemblies
The permeability barrier of nuclear pore complexes (NPCs) controls bulk nucleocytoplasmic exchange. It consists of nucleoporin domains rich in phenylalanine-glycine motifs (FG domains). As a bottom-up nanoscale model for the permeability barrier, we have used planar films produced with three different end-grafted FG domains, and quantitatively analyzed the binding of two different nuclear transport receptors (NTRs), NTF2 and Importin b, together with the concomitant film thickness changes. NTR binding caused only moderate changes in film thickness; the binding isotherms showed negative cooperativity and could all be mapped onto a single master curve. This universal NTR binding behavior âa key element for the transport selectivity of the NPC âwas quantitatively reproduced by a physical model that treats FG domains as regular, flexible polymers, and NTRs as spherical colloids with a homogeneous surface, ignoring the detailed arrangement of interaction sites along FG domains and on the NTR surface
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