Demonstration of short-haul aircraft aft noise reduction techniques on a twenty inch (50.8 cm) diameter fan, volume 1

Tests of a 20 inch diameter, low tip speed, low pressure ratio fan which investigated aft fan noise reduction techniques are reported. These techniques included source noise reduction features of selection of vane-blade ratio to reduce second harmonic noise, spacing effects, and lowering the Mach number through a vane row. Aft suppression features investigated included porosity effects, variable depth treatment, and treatment regenerated flow noise. Initial results and selected comparisons are presented

Quiet Clean Short-haul Experimental Engine (QCSEE). Aerodynamic and aeromechanical performance of a 50.8 cm (20 inch) diameter 1.34 PR variable pitch fan with core flow

The fan aerodynamic and aeromechanical performance tests of the quiet clean short haul experimental engine under the wing fan and inlet with a simulated core flow are described. Overall forward mode fan performance is presented at each rotor pitch angle setting with conventional flow pressure ratio efficiency fan maps, distinguishing the performance characteristics of the fan bypass and fan core regions. Effects of off design bypass ratio, hybrid inlet geometry, and tip radial inlet distortion on fan performance are determined. The nonaxisymmetric bypass OGV and pylon configuration is assessed relative to both total pressure loss and induced circumferential flow distortion. Reverse mode performance, obtained by resetting the rotor blades through both the stall pitch and flat pitch directions, is discussed in terms of the conventional flow pressure ratio relationship and its implications upon achievable reverse thrust. Core performance in reverse mode operation is presented in terms of overall recovery levels and radial profiles existing at the simulated core inlet plane. Observations of the starting phenomena associated with the initiation of stable rotor flow during acceleration in the reverse mode are briefly discussed. Aeromechanical response characteristics of the fan blades are presented as a separate appendix, along with a description of the vehicle instrumentation and method of data reduction

Outcomes after angiography with sodium bicarbonate and acetylcysteine

Background: Intravenous sodium bicarbonate and oral acetylcysteine are widely used to prevent acute kidney injury and associated adverse outcomes after angiography without definitive evidence of their efficacy. Methods: Using a 2-by-2 factorial design, we randomly assigned 5177 patients at high risk for renal complications who were scheduled for angiography to receive intravenous 1.26% sodium bicarbonate or intravenous 0.9% sodium chloride and 5 days of oral acetylcysteine or oral placebo; of these patients, 4993 were included in the modified intention-to-treat analysis. The primary end point was a composite of death, the need for dialysis, or a persistent increase of at least 50% from baseline in the serum creatinine level at 90 days. Contrast-associated acute kidney injury was a secondary end point. Results: The sponsor stopped the trial after a prespecified interim analysis. There was no interaction between sodium bicarbonate and acetylcysteine with respect to the primary end point (P=0.33). The primary end point occurred in 110 of 2511 patients (4.4%) in the sodium bicarbonate group as compared with 116 of 2482 (4.7%) in the sodium chloride group (odds ratio, 0.93; 95% confidence interval [CI], 0.72 to 1.22; P=0.62) and in 114 of 2495 patients (4.6%) in the acetylcysteine group as compared with 112 of 2498 (4.5%) in the placebo group (odds ratio, 1.02; 95% CI, 0.78 to 1.33; P=0.88). There were no significant between-group differences in the rates of contrast-associated acute kidney injury. Conclusions: Among patients at high risk for renal complications who were undergoing angiography, there was no benefit of intravenous sodium bicarbonate over intravenous sodium chloride or of oral acetylcysteine over placebo for the prevention of death, need for dialysis, or persistent decline in kidney function at 90 days or for the prevention of contrast-associated acute kidney injury. (Funded by the U.S. Department of Veterans Affairs Office of Research and Development and the National Health and Medical Research Council of Australia; PRESERVE ClinicalTrials.gov number, NCT01467466.

In-Stent Restenosis in Saphenous Vein Grafts (from the DIVA Trial)

Saphenous vein grafts (SVGs) have high rates of in-stent restenosis (ISR). We compared the baseline clinical and angiographic characteristics of patients and lesions that did develop ISR with those who did not develop ISR during a median follow-up of 2.7 years in the DIVA study (NCT01121224). We also examined the ISR types using the Mehran classification. ISR developed in 119 out of the 575 DIVA patients (21%), with similar incidence among patients with drug-eluting stents and bare-metal stents (BMS) (21% vs 21%, p = 0.957). Patients in the ISR group were younger (67 ± 7 vs 69 ± 8 years, p = 0.04) and less likely to have heart failure (27% vs 38%, p = 0.03) and SVG lesions with Thrombolysis In Myocardial Infarction 3 flow before the intervention (77% vs 83%, p <0.01), but had a higher number of target SVG lesions (1.33 ± 0.64 vs 1.16 ± 0.42, p <0.01), more stents implanted in the target SVG lesions (1.52 ± 0.80 vs 1.31 ± 0.66, p <0.01), and longer total stent length (31.37 ± 22.11 vs 25.64 ± 17.42 mm, p = 0.01). The incidence of diffuse ISR was similar in patients who received drug-eluting-stents and BMS (57% vs 54%, p = 0.94), but BMS patients were more likely to develop occlusive restenosis (17% vs 33%, p = 0.05). © 202

Global nuts and local mangoes: a critical reading of the UNDP Growing Sustainable Business Initiative in Kenya

This article provides a conceptual and empirical assessment of UN brokered partnerships that seek to deepen or create inclusive and sustainable agricultural supply chains in sub-Saharan Africa. More specifically it appraises the decision-making mechanisms, processes of partnership brokerage and project implementation within the UNDP Growing Sustainable Business Initiative (GSB) in Kenya. The paper argues that the lack of bottom-up participation in decision-making mechanisms and the predominantly economic imperatives driving the GSB partnership projects have failed to reach out to the partnerships’ intended beneficiaries—Kenyan small producers of nuts and mangoes. In conclusion it is suggested that opening up the GSB platform might hold the promise of reconciling sustainable business models with (some) poverty reduction

Population policies, programmes and the environment

Human consumption is depleting the Earth's natural resources and impairing the capacity of life-supporting ecosystems. Humans have changed ecosystems more rapidly and extensively over the past 50 years than during any other period, primarily to meet increasing demands for food, fresh water, timber, fibre and fuel. Such consumption, together with world population increasing from 2.6 billion in 1950 to 6.8 billion in 2009, are major contributors to environmental damage. Strengthening family-planning services is crucial to slowing population growth, now 78 million annually, and limiting population size to 9.2 billion by 2050. Otherwise, birth rates could remain unchanged, and world population would grow to 11 billion. Of particular concern are the 80 million annual pregnancies (38% of all pregnancies) that are unintended. More than 200 million women in developing countries prefer to delay their pregnancy, or stop bearing children altogether, but rely on traditional, less-effective methods of contraception or use no method because they lack access or face other barriers to using contraception. Family-planning programmes have a successful track record of reducing unintended pregnancies, thereby slowing population growth. An estimated $15 billion per year is needed for family-planning programmes in developing countries and donors should provide at least$5 billion of the total, however, current donor assistance is less than a quarter of this funding target

Remote ischaemic preconditioning versus sham procedure for abdominal aortic aneurysm repair: An external feasibility randomized controlled trial

© 2015 Mouton et al. Background: Despite advances in perioperative care, elective abdominal aorta aneurysm (AAA) repair carries significant morbidity and mortality. Remote ischaemic preconditioning (RIC) is a physiological phenomenon whereby a brief episode of ischaemia-reperfusion protects against a subsequent longer ischaemic insult. Trials in cardiovascular surgery have shown that RIC can protect patients' organs during surgery. The aim of this study was to investigate whether RIC could be successfully introduced in elective AAA repair and to obtain the information needed to design a multi-centre RCT. Methods: Consecutive patients presenting for elective AAA repair, using an endovascular (EVAR) or open procedure, in a single large city hospital in the UK were assessed for trial eligibility. Patients who consented to participate were randomized to receive RIC (three cycles of 5 min ischaemia followed by 5 min reperfusion in the upper arm immediately before surgery) or a sham procedure. Patients were followed up for 6 months. We assessed eligibility and consent rates, the logistics of RIC implementation, randomization, blinding, data capture, patient and staff opinion, and variability and frequency of clinical outcome measures. Results: Between January 2010 and December 2012, 98 patients were referred for AAA repair, 93 were screened, 85 (91 %) were eligible, 70 were approached for participation and 69 consented to participate; 34 were randomized to RIC and 35 to the sham procedure. There was a greater than expected variation in the complexity of EVAR that impacted the outcomes. Acute kidney injury occurred in 28 (AKIN 1: 23 %; AKIN 2: 15 % and AKIN 3: 3 %) and 7 (10 %) had a perioperative myocardial infarction. Blinding was successful, and interviews with participants and staff indicated that the procedure was acceptable. There were no adverse events secondary to the intervention in the 6 months following the intervention. Conclusions: This study provided essential information for the planning and design of a multi-centre RCT to assess effectiveness of RIC for improving clinical outcomes in elective AAA repair. Patient consent was high, and the RIC intervention was carried out with minimal disruption to clinical care. The allocation scheme for a definite trial should take into account both the surgical procedure and its complexity to avoid confounding the effect of the RIC, as was observed in this study. Trial registration: Current Controlled Trials ISRCTN19332276(date of registration: 16 March 2012). The trial protocol is available from the corresponding author