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Nanosecond pulsed laser blackening of copper
No full textNanosecond (12ns) pulsed laser processing of copper at 532nm resulted in the formation of homogenously distributed, highly organized microstructures. This led to the fabrication of large area black copper substrates with absorbance of over 97% in the spectral range from 250 nm to 750nm, and a broadband absorbance of over 80% between 750nm and 2500nm. Optical and chemical analyses of the fabricated black metal are presented and discussed. The employed laser is an industrially adaptable source and the presented technique for fabrication of black copper could find applications in broadband thermal radiation sources, solar energy absorbers, irradiative heat transfer devices, and thermophotovoltaics
Metaphysical spookiness?:the collective responsibility of company directors
No full textAccording to both corporate governance codes and company law the directors of a company have a collective responsibility. This article explores collective, or collegiate, decision-making and, perhaps more importantly, collective responsibility. The collective responsibility of directors is currently operationalized only by converting it into an individual responsibility and liability. The purpose of this article is to reveal how a more openly collective approach to board responsibilities and board liabilities could be useful and practical despite the fact that its theoretical basis may require some metaphysical spookiness
Peak cardiac power output, measured noninvasively, is a powerful predictor of outcome in chronic heart failure
No full textBackground-The cardiac output (CO) response to exercise and other invasively derived hemodynamic variables has beeh variably described to provide better prognostication than peak Vo(2) in patients with chronic heart failure. Using noninvasive measurements of CO during exercise, we compared the prognostic value of peak CO and cardiac power to peak Vo(2) in chronic heart failure patients.Method and Results-One hundred seventy-one consecutive patients with chronic heart failure underwent symptom limited bicycle exercise with noninvasive estimation Of CO using an inert gas rebreathing method. An accurate measure of peak CO was obtained in 148 patients (85% of patients; mean age, 53 +/- 14 years; 80% male; left ventricular ejection fraction, 24 +/- 12%; ischemic etiology, 34%). Peak cardiac power was derived from the product of the peak mean arterial blood pressure and CO divided by 451. End points consisted of death, urgent heart transplant, or left ventricular assist device implantation. Duration of follow-up averaged 337 +/- 252 days (median, 295 days). Univariate and multivariate analysis were performed. The variables analyzed included peak Vo(2) peak CO, peak cardiac power, VE/VCO2 slope, and Vo(2) at anaerobic threshold. Event-free survival for the entire cohort was 83% with 5 deaths, 4 left ventricular assist device implants, and 16 urgent transplants. Peak Vo(2) was 12.9 +/- 4.5 mL/kg per min, and peak cardiac power was 1.7 +/- 0.9 W. Peak Vo(2), peak CO, peak cardiac power, VE/VCO2 slope, and Vo(2) at anaerobic threshold were predictive of outcome on univariate analysis. On multivariate analysis, peak cardiac power and peak CO were predictive of outcome with peak cardiac power being the most powerful independent predictor of outcome (P=0.01).Conclusions-Peak cardiac power, measured noninvasively, is an independent predictor Of Outcome that can enhance the prognostic power of peak Vo(2) in the evaluation of patients with heart failure. (Circ Heart Fail. 2009;2:33-38.)</p
Effect of high-dose allopurinol on exercise in patients with chronic stable angina:a randomised, placebo controlled crossover trial
No full textBackground Experimental evidence suggests that xanthine oxidase inhibitors can reduce myocardial oxygen consumption for a particular stroke volume. If such an effect also occurs in man, this class of inhibitors could become a new treatment for ischaemia in patients with angina pectoris. We ascertained whether high-dose allopurinol prolongs exercise capability in patients with chronic stable angina. Methods 65 patients (aged 18-85 years) with angiographically documented coronary artery disease, a positive exercise tolerance test, and stable chronic angina pectoris (for at least 2 months) were recruited into a double-blind, randomised, placebo-controlled, crossover study in a hospital and two infirmaries in the UK. We used computer-generated randomisation to assign patients to allopurinol (600 mg per day) or placebo for 6 weeks before crossover. Our primary endpoint was the time to ST depression, and the secondary endpoints were total exercise time and time to chest pain. We did a completed case analysis. This study is registered as an International Standard Randomised Controlled Trial, number IS RCTN 82040078. Findings In the first treatment period, 31 patients were allocated to allopurinol and 28 were analysed, and 34 were allocated to placebo and 32 were analysed. In the second period, all 60 patients were analysed. Allopurinol increased the median time to ST depression to 298 s (IQR 211-408) from a baseline of 232 s (182-380), and placebo increased it to 249 s (200-375; p=0.0002). The point estimate (absolute difference between allopurinol and placebo) was 43 s (95% CI 31-58). Allopurinol increased median total exercise time to 393 s (IQR 280-519) from a baseline of 301 s (251-447), and placebo increased it to 307s (232-430; p=0.0003); the point estimate was 58 s (95% Cl 45-77). Allopurinol increased the time to chest pain from a baseline of 234 s (IQR 189-382) to 304 s (222-421), and placebo increased it to 272 s (200-380; p=0.001); the point estimate was 38s (95% Cl 17-55). No adverse effects of treatment were reported. Interpretation Allopurinol seems to be a useful, inexpensive, well tolerated, and safe anti-ischaemic drug for patients with angina.</p
Optimisation of the Anti-Trypanosoma brucei Activity of the Opioid Agonist U50488
No full textScreening of the Sigma-Aldrich Library of Pharmacologically Active Compounds (LOPAC) against cultured Trypanosoma brucei, the causative agent of African sleeping sickness, resulted in the identification of a number of compounds with selective antiproliferative activity over mammalian cells. These included (+)-(1R,2R)-U50488, a weak opioid agonist with an EC50 value of 59 nm as determined in our T. brucei in vitro assay reported previously. This paper describes the modification of key structural elements of U50488 to investigate structure-activity relationships (SAR) and to optimise the antiproliferative activity and pharmacokinetic properties of this compound.</p
How do carers of people with long term neurological conditions experience the provision of replacement care:Final report to the Department of Health R&D grant 053/0012
No full textThe effects of sustained forest use on hillslope soil hydraulic conductivity in the Middle Mountains of Central Nepal
No full textThis work investigated the multi-decadal changes in field saturated hydraulic conductivity, Kfs, beneath severely degraded pasture, natural forest and two mature planted Pinus roxburghii stands between two sets of measurements made in 1986 and 2011 at the same locations in the Middle Mountains of Central Nepal.Multiple measurements of Kfs were made at the four sites, both at the surface and at depths of 005–015, 015–025 and 025–050 m. The Kfs results were subsequently combined with rainfall intensities associated with different time intervals to infer multi-decadal changes in dominant hillslope stormflow pathways. The widely assumed hydrological benefits of reforesting degraded land through the enhancement of near-surface permeability due to such factors as the incorporation of a greater amount of organic matter, formation of macropores, as well as root development were not observed in this study. Continued heavy use of the natural and planted forests of the Middle Mountains, particularly the removal of understory vegetation and leaf litter, and cattle grazing, are considered to be the chief causal factors of the presently observed deterioration in forest hydrological functioning. This situation is typical not only of the Middle Mountain Zone across the Himalaya but is also observed in other densely populated parts of South and South-East Asia. The key conclusion of this work is that simply planting trees in degraded landscapes is not sufficient in itself to restore watershed hydrological functioning. Attention also needs to be given to on-going management of the reforested areas to balance product usage with watershed functions.</p
Collective teacher efficacy, pupil attainment and socio-economic status in primary school
No full textCollective teacher efficacy (CTE) refers to the collective perception in a school that teachers make an educational difference to their pupils over and above the impact of their social circumstances. This study explored the relationships between CTE, socio-economic status (SES) and pupil attainment levels in reading, writing and mathematics (at the whole primary school level). Sixty-six teachers in 15 out of 19 schools in a small Local Authority participated. Significant positive relationships were found between SES and attainment in reading and mathematics (but not writing). However, significant positive relationships were also found between CTE and attainment in reading and writing (but not mathematics). Neither SES nor CTE independently accounted for a statistically significant proportion of the total variance in attainment. However, CTE appeared to have a much stronger independent impact than SES in writing (and also a modest independent impact in reading). One school with an atypical pattern of high CTE and high attainment despite low SES was studied in depth. Here, school climate or ethos, high quality in-service training and a focus upon pedagogy were perceived as the most potent factors in raising attainment. When these factors serve to heighten CTE, the impact of SES on pupil attainment may be reduced, and this may be easier in some subjects than others
SuBETooL ( Sustainable Urban Built Environment Tool), framework and protocol for assessing sustainability. Developed with Hilson Moran and Reading University and put into practice by Hilson Moran in 2009.
No full textThis new framework and tool for assessing the sustainability of masterplans and existing communities is currently used in the industry worldwide. SuBET has been developed over the past 4 years in partnership with Professor Clements-Croome, and Hilson Moran. The strength of SuBETool is that it demonstrates clearly, from the start of masterplanning, what can be achieved in terms of the performance of the proposed development.This framework has changed dramatically the treatment of the masterplanning process as a whole –integrated- system. This has had a major impact on the creation of a more integrated approach for the master planning process benefiting the community of practice, and has achieved International impact in strategic development in the UK, EU and the middle East. This research has replaced, the traditional perspective of master-planning as a linear process concerned with the end state is out-dated and now allows coordination of the plural processes of negotiating sustainable place development.his framework comes with a manual of guidelines which explain explicitly the 75 identified indicators, participation process and the compliance requirement for each indicator, and an assessment system. This proprietary framework has been published internally by Hilson Moran, Husam Al Waer and Derek Croome (2009-present). This framework is available upon request
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