Data summary and computer program for axial-flow pump rotor performance

Assembly of noncavitating blade element performance data for axial-flow pump rotor configurations has been collected and organized. Program facilitates handling large amounts of experimental data involved and may be used as data reduction program to process flow and performance measurements from other axial-flow pump configurations

Six-year changes in body mass index and cardiorespiratory fitness of English schoolchildren from an affluent area

We compared values of body mass index (BMI) and cardiorespiratory fitness (20 m shuttle-run test) of n=157 boys and n=150 girls aged 10-11 measured in 2014 with measures from 2008 and 1998. Boys' fitness was lower (d=0.68) in 2014 than 2008, despite a small (d=0.37) decline in BMI. Girl's BMI changed trivially (d=0.08) but cardiorespiratory fitness was lower (d=0.47) in 2014 than 2008. This study suggests fitness is declining at 0.95% per year, which exceeds the 0.8% rate of decline we reported between 1998 and 2008 and is double the global average of 0.43%. Declines in fitness were independent of changes in BMI suggesting continued reductions in English children's habitual physical activity levels

Simultaneous existence of two spin-wave modes in ultrathin Fe/GaAs(001) films studied by Brillouin Light Scattering: experiment and theory

A double-peaked structure was observed in the {\it in-situ} Brillouin Light Scattering (BLS) spectra of a 6 \AA$$ thick epitaxial Fe/GaAs(001) film for values of an external magnetic field $H$, applied along the hard in plane direction, lower than a critical value $H_c\simeq 0.9$ kOe. This experimental finding is theoretically interpreted in terms of a model which assumes a non-homogeneous magnetic ground state characterized by the presence of perperpendicular up/down stripe domains. For such a ground state, two spin-wave modes, namely an acoustic and an optic mode, can exist. Upon increasing the field the magnetization tilts in the film plane, and for $H \ge H_{c}$ the ground state is homogeneous, thus allowing the existence of just a single spin-wave mode. The frequencies of the two spin-wave modes were calculated and successfully compared with the experimental data. The field dependence of the intensities of the corresponding two peaks that are present in the BLS spectra was also estimated, providing further support to the above-mentioned interpretation.Comment: Shortened version (7 pages). Accepted for publication in Physical Review

Brillouin scattering studies in Fe3_3O4_4 across the Verwey transition

Brillouin scattering studies have been carried out on high quality single crystals of Fe$_3$O$_4$ with [100] and [110] faces in the temperature range of 300 to 30 K. The room temperature spectrum shows a surface Rayleigh wave (SRW) mode at 8 GHz and a longitudinal acoustic (LA) mode at 60 GHz. The SRW mode frequency shows a minimum at the Verwey transition temperature $T_V$ of 123 K. The softening of the SRW mode frequency from about 250 K to $T_V$ can be quantitatively understood as a result of a decrease in the shear elastic constant C$_{44}$, arising from the coupling of shear strain to charge fluctuations. On the other hand, the LA mode frequency does not show any significant change around $T_V$, but shows a large change in its intensity. The latter shows a maximum at around 120 K in the cooling run and at 165 K in the heating run, exhibiting a large hysteresis of 45 K. This significant change in intensity may be related to the presence of stress-induced ordering of Fe$^{3+}$ and Fe$^{2+}$ at the octahedral sites, as well as to stress-induced domain wall motion.Comment: 14 pages, 3 figures, accepted in Physical Review B 200

Effects of alteplase for acute stroke on the distribution of functional outcomes: a pooled analysis of 9 trials

Background—Thrombolytic therapy with intravenous alteplase within 4.5 hours of ischemic stroke onset increases the overall likelihood of an excellent outcome (no, or nondisabling, symptoms). Any improvement in functional outcome distribution has value, and herein we provide an assessment of the effect of alteplase on the distribution of the functional level by treatment delay, age, and stroke severity. Methods—Prespecified pooled analysis of 6756 patients from 9 randomized trials comparing alteplase versus placebo/open control. Ordinal logistic regression models assessed treatment differences after adjustment for treatment delay, age, stroke severity, and relevant interaction term(s). Results—Treatment with alteplase was beneficial for a delay in treatment extending to 4.5 hours after stroke onset, with a greater benefit with earlier treatment. Neither age nor stroke severity significantly influenced the slope of the relationship between benefit and time to treatment initiation. For the observed case mix of patients treated within 4.5 hours of stroke onset (mean 3 hours and 20 minutes), the net absolute benefit from alteplase (ie, the difference between those who would do better if given alteplase and those who would do worse) was 55 patients per 1000 treated (95% confidence interval, 13–91; P=0.004). Conclusions—Treatment with intravenous alteplase initiated within 4.5 hours of stroke onset increases the chance of achieving an improved level of function for all patients across the age spectrum, including the over 80s and across all severities of stroke studied (top versus bottom fifth means: 22 versus 4); the earlier that treatment is initiated, the greater the benefit

Low dose aspirin and cognitive function in middle aged to elderly adults: randomised controlled trial

Objective To determine the effects of low dose aspirin on cognitive function in middle aged to elderly men and women at moderately increased cardiovascular risk

Birmingham’s Eastside story: making steps towards sustainability?

Sustainability has come to play a dominant discursive role in the UK planning system, particularly relating to urban regeneration. The purpose of this paper is to evaluate the role that sustainability plays in a major regeneration programme, known as Eastside, currently underway in Birmingham, the UK. That this £6 billion redevelopment is now widely talked about by such key players as Birmingham City Council and the Regional Development Agency, Advantage West Midlands, as having a central sustainability agenda points to the growing importance of the ideal of sustainability in planning and regeneration agendas. In this paper, we investigate in detail how and why sustainability has become part of the planning discourse for Eastside and critically evaluate what impact, if any, this is having on public policy decision-making

Why do earlier-arriving migratory birds have better breeding success?

In migratory birds, early arrival on breeding sites has been widely associated with greater breeding success, but the mechanisms driving these benefits are rarely known. Acquisition of higher quality territories or carry-over effects of better non-breeding season conditions are frequently cited as possible mechanisms through which early-arrivers can achieve greater reproductive output. However, benefits of early arrival could also result from increased time available for breeding, independent of variation in territory quality and associated fitness. Increased time available for breeding among early arrivers could directly influence reproductive success through the time available for replacement clutches following nest loss. However, the benefits of replacement clutches may also depend on seasonal variation in nest survival, and the consequences for juvenile recruitment of hatching at different times in the season. Here we construct a simulation model to explore the potential for time-constrained capacity for replacement clutches to drive relationships between timing of arrival and reproductive success in avian migratory systems, and the influence of seasonal variation in both nest survival and subsequent offspring recruitment probability on these relationships. We show that positive relationships between arrival timing and reproductive success can arise solely through the greater time capacity for replacement clutches among early-arrivers, even when juvenile recruitment declines seasonally and thus later re-nesting attempts contribute fewer recruits to the population. However, these relationships vary depending on the seasonal pattern of nest survival. The benefits of early arrival are greatest when nest survival rates are constant or decline seasonally, and early arrival is least beneficial when nest success rates increase over the breeding season, although re-nesting capacity can mitigate this effect. The time benefits of early arrival facilitating replacement clutches following nest loss may therefore be an important source of selection on migratory timings, and empirical measures of seasonal variation in nest survival, re-nesting and juvenile recruitment rates are needed in order to identify the costs and benefits associated with individual migration phenology and the selection pressures influencing migratory timings

Anharmonic vs. relaxational sound damping in glasses: I. Brillouin scattering from densified silica

This series discusses the origin of sound damping and dispersion in glasses. In particular, we address the relative importance of anharmonicity versus thermally activated relaxation. In this first article, Brillouin-scattering measurements of permanently densified silica glass are presented. It is found that in this case the results are compatible with a model in which damping and dispersion are only produced by the anharmonic coupling of the sound waves with thermally excited modes. The thermal relaxation time and the unrelaxed velocity are estimated.Comment: 9 pages with 7 figures, added reference

Elastic properties of B-C-N films grown by N2-reactive sputtering from boron carbide targets

The following article appeared in Journal of Applied Physics 114.21 (2013): 213508 and may be found at http://scitation.aip.org/content/aip/journal/jap/114/21/10.1063/1.4837655Boron-carbon-nitrogen films were grown by RF reactive sputtering from a B4C target and N2 as reactive gas. The films present phase segregation and are mechanically softer than boron carbide films (a factor of more than 2 in Young's modulus). This fact can turn out as an advantage in order to select buffer layers to better anchor boron carbide films on substrates eliminating thermally induced mechanical tensions.This work has been supported by Spanish MINECO under contracts MAT2009-08786 and MAT2012-37276- C03-01 as well as by the Madrid Regional Government though contract S2009/MAT-1756