Exploratory studies of the cruise performance of upper surface blown configurations: Experimental program, high-speed pressure tests

Basic pressure data are presented which was obtained from an experimental study of upper-surface blown configurations at cruise. The high-speed (subsonic) experimental work, studying the aerodynamic effects of wing-nacelle geometric variations, was conducted around semi-span model configurations composed of diversified, interchangeable components. Power simulation was provided by high-pressure air ducted through closed forebody nacelles. Nozzle geometry was varied across size, exit aspect ratio, exit position and boattail angle. Both 3-D force and 2-D pressure measurements were obtained at cruise Mach numbers from 0.5 to 0.8 and at nozzle pressure ratios up to about 3.0. The experimental investigation was supported by an analytical synthesis of the system using a vortex lattice representation with first-order power effects. Results are also presented from a compatibility study in which a short-haul transport is designed on the basis of the aerodynamic findings in the experimental study as well as acoustical data obtained in a concurrent program. High-lift test data are used to substantiate the projected performance of the selected transport design

Exploratory studies of the cruise performance of upper surface blown configuration: Experimental program, high-speed force tests

The work to develop a wing-nacelle arrangement to accommodate a wide range of upper surface blown configuration is reported. Pertinent model and installation details are described. Data of the effects of a wide range of nozzle geometric variations are presented. Nozzle aspect ratio, boattail angle, and chordwise position are among the parameters investigated. Straight and swept wing configurations were tested across a range of nozzle pressure ratios, lift coefficients, and Mach numbers

Exploratory studies of the cruise performance of upper surface blown configurations. Experimental program: Test facilities, model design instrumentation, and lowspeed, high-lift tests

The model hardware, test facilities and instrumentation utilized in an experimental study of upper surface blown configurations at cruise is described. The high speed (subsonic) experimental work, studying the aerodynamic effects of wing nacelle geometric variations, was conducted around semispan model configurations composed of diversified, interchangeable components. Power simulation was provided by high pressure air ducted through closed forebody nacelles. Nozzle geometry was varied across size, exit aspect ratio, exit position and boattail angle. Three dimensional force and two dimensional pressure measurements were obtained at cruise Mach numbers from 0.5 to 0.8 and at nozzle pressure ratios up to about 3.0. The experimental investigation was supported by an analytical synthesis of the system using a vortex lattice representation with first order power effects. Results are also presented from a compatibility study in which a short haul transport is designed on the basis of the aerodynamic findings in the experimental study as well as acoustical data obtained in a concurrent program. High lift test data are used to substantiate the projected performance of the selected transport design

Soliton response to transient trap variations

The response of bright and dark solitons to rapid variations in an expulsive longitudinal trap is investigated. We concentrate on the effect of transient changes in the trap frequency in the form of temporal delta kicks and the hyperbolic cotangent functions. Exact expressions are obtained for the soliton profiles. This is accomplished using the fact that a suitable linear Schrodinger stationary state solution in time can be effectively combined with the solutions of non-linear Schrodinger equation, for obtaining solutions of the Gross-Pitaevskii equation with time dependent scattering length in a harmonic trap. Interestingly, there is rapid pulse amplification in certain scenarios

Exploratory studies of the cruise performance of upper surface blown configurations

The data and major conclusions obtained from an experimental/analytical study of upper-surface blown (USB) configurations at cruise are summarized. The high-speed (subsonic) experimental work, studying the aerodynamic effects of wing-nacelle geometric variations, was conducted around semi-span model configurations composed of diversified, interchangeable components. Power simulation was provided by high pressure air ducted through closed forebody nacelles. Nozzle geometry was varied across size, exit aspect ratio, exit position and boattail angle. Both 3-D force and 2-D pressure measurements were obtained at cruise Mach numbers from 0.5 to 0.8 and at nozzle pressure ratios up to about 3.0. The experimental investigation was supported by an analytical synthesis of the system using a vortex lattice representation with first-order power effects. Results are also presented from a compatibility study in which a short-haul transport is designed on the basis of the aerodynamic findings in the experimental study as well as acoustical data obtained in a concurrent program. High-lift test data are used to substantiate the projected performance of the selected transport design

Development of a complex intervention to support exercise self-management for people with Parkinson's.

Purpose: The value of exercise for people with Parkinson's (PwP) is undisputed, and is associated with improved health outcomes and potential to slow down the rate of symptom decline. However, the optimum means to support long-term participation in exercise remains undetermined. Current exercise provision within physiotherapy is commonly time limited. Moreover, research has shown that when current services cease, adherence declines and the effects on outcomes diminish. Therefore, a sustainable means of maintaining activity, beyond the end of normal physiotherapy care, is required, which necessitates a different approach to support People PwP to be more active. Aims: To develop an evidence based intervention to equip PwP to self-manage their exercise participation. Methods: A multi-step mixed methods approach was adopted. A systematic review of the literature exploring barriers and motivators to exercise and a comprehensive review of the exercise literature for PwP was conducted. Consultation with a convenience sample drawn from UK wide specialist physiotherapists and the Parkinson's community was conducted to explore barriers and facilitators to exercise delivery and participation. The findings were used to inform the development of a multi-component intervention aimed at promoting exercise self-management. PwP were involved in refining the intervention. Results: The literature review identified that simply prescribing exercise in isolation is ineffective to promote long-term changes in exercise behaviour. Amalgamating findings from the systematic and comprehensive literature reviews with consultation finding identified key ingredients to support long-term exercise self-management were identified. These included: individualised exercise programmes, contextualised education, and the provision of strategies to support PwP to develop an exercise habit. While the benefits of exercise were widely acknowledged, a need was identified for services to develop exercise self-confidence, to empower PwP with the knowledge and skills they need to embed exercise within their everyday routine. Access to professionals with specialist Parkinson's training was highly valued, either on a 1:1 basis or within a group. 1:1 interventions were thought to develop confidence, whereas group-based exercise provided opportunity for shared learning and development of a social network. Transport and costs were reported as key barriers; accessibility and sustainability were key to long-term participation. This process informed the development of the PDConnect programme. PDConnect is an evidence-informed exercise intervention underpinned by empowerment theory, with the aim of providing PwP with a toolkit of behaviour change techniques to promote participation in exercise and exercise self-management. The PDConnect combines specialist physiotherapy, group-based exercise and self-management support, with education and behaviour change strategies threaded throughout. The programme consists of three components: (i) six sessions of 1-1-specialist physiotherapy delivered at home; (ii) 12 sessions of group-based exercise, delivered once a week for 12 weeks; (iii) 12 weeks of self-management, with a support session each month. Conclusion(s): Aligning with the Medical Research Council guidelines for developing complex interventions, the feasibility and acceptability of the PDConnect programme is currently being tested and evaluated by those delivering and receiving the intervention. Impact: Promoting exercise self-management is beneficial to the NHS to reduce health service utilisation and prevent secondary complications related to sedentary behaviour. Funding acknowledgements: This development of the PDConnect intervention was not funded. Current work to explore the feasibility and acceptability of the PDConnect intervention is jointly funded by Parkinson's UK and the Chief Scientist Office, Scotland

Controlling pulse propagation in optical fibers through nonlinearity and dispersion management

In case of the nonlinear Schr\"odinger equation with designed group velocity dispersion, variable nonlinearity and gain/loss; we analytically demonstrate the phenomenon of chirp reversal crucial for pulse reproduction. Two different scenarios are exhibited, where the pulses experience identical dispersion profiles, but show entirely different propagation behavior. Exact expressions for dynamical quasi-solitons and soliton bound-states relevant for fiber communication are also exhibited.Comment: 4 pages, 5 eps figure

Long Term Outcome of Childhood Bicuspid Aortic Valve

The most common congenital heart defect is a bicuspid aortic valve (BAV), which is often genetic and the cause is unknown. The defect occurs in only 1% of the general population. A BAV is not able to fully stop blood from leaking back into the heart, which is known as aortic regurgitation. Another common issue with a BAV is that it may be too stiff to fully open, which is known as aortic stenosis. In early childhood, children with aortic stenosis often need palliation with a balloon or surgical valvotomy. As these children develop, they may need subsequent, more definitive procedures such as a Ross procedure, insertion of a tissue valve or mechanical valve, or a valve repair. These definitive operations are used to address recurrent aortic stenosis or regurgitation. As a result, comparing the long-term complications of valve interventions in infancy was an area of considerable interest. The goal of this study was to compare whether one procedure is more effective in providing a more functional status in adulthood since comparative data on the morbidity and mortality associated with each definitive repair in a contemporaneous cohort is lacking. Clinical evidence suggests that repeat surgical procedures are very common in all surgical interventions for bicuspid aortic valve with aortic stenosis in childhood. Incidences of a greater number of aortic valve surgery is associated with a higher incidence of surgical complications and endocarditis. Long-term follow up on the odds of a composite adverse outcome are less with a Ross procedure.https://digitalcommons.unmc.edu/surp2021/1011/thumbnail.jp

The Politics of Commerce : The Congress of Chambers of Commerce of the Empire, 1886-1914

Peer reviewedPublisher PD