What price advice?

"Ever time you brush our teeth; every time you fill our petrol tank; every time you shop at the supermarket virtually every time that you spend money - somebody is making money. Why not share in the profits they make off you?" That sentence was the injection of my passion for equities 40 years ago.peer-reviewe

Systemic inflammation in COPD is not influenced by pulmonary rehabilitation

Purpose: Pulmonary rehabilitation is known to lead to improvements in exercise tolerance, health-related quality of life and help reduce symptoms. Exercise, one of the largest components of such an intervention, although of great benefit, can increase the inflammatory response related to chronic obstructive pulmonary disease, depending on intensity and duration. Through this study, the effects of a 12week, high-intensity PR programme on COPD inflammatory-related markers were investigated. Materials and methods: This study is a longitudinal, observational type of study. Sixty COPD patients were enrolled, 49 of which completed the programme. A 2-h high-intensity PR programme was delivered, twice weekly for 12 weeks. The following markers were assessed at baseline, 4, 8 and 12 weeks through rehabilitation – C-reactive protein, erythrocyte sedimentation rate, neutrophil, eosinophil counts, complete blood count, six-minute walk test and St. George’s Respiratory Questionnaire. Serum amyloid A levels were assessed at baseline, week 8 and 12 and exhaled NO at baseline and upon completion of the programme. Results: This 12-week PR programme resulted in no changes in the inflammatory markers but resulted in significant improvements in both the 6MW distance and health quality of life. Conclusions: Beneficial effects on functional and HRQoL measures resulted, which, however, appear unrelated to changes in the systemic inflammatory markers.peer-reviewe

Experimental validation of a distributed parameter piezoelectric bimorph cantilever energy harvester

Recent rapid advances in low-power portable electronic applications have motivated researchers and industry to explore schemes to embed an endless power supply mechanism within these systems. These self-charging embedded power supply systems convert ambient energy (vibration, solar, wind, etc) into electrical energy and subsequently provide power to these portable applications. Ambient vibration is one of the most promising sources of energy as it is abundantly present in indoor/outdoor systems. This paper discusses briefly the mathematical model of a bimorph piezoelectric cantilever beam with distributed inertia, and its experimental validation. Research on such a component typically included a tip mass, which reduced the influence of the distributed inertia of the beam and restricted effective operation to low frequencies. The present work excludes the tip mass and only the distributed mass of the harvester is considered. Due to the coupled electromechanical nature of piezoelectric materials, the effects of electrical coupling on the mechanical properties of the harvester are investigated, particularly the dependence of the induced additional stiffness and damping on the electrical load. Both the model and the experimental results show that the resonance frequency and the response amplitude of the harvester exhibit considerable shifts due to the electrical coupling. The experimental work uses both magnitude and Nyquist plots of the electromechanical frequency response functions to thoroughly validate the accuracy and applicability of the distributed parameter model at higher frequencies than previously considered. © 2010 IOP Publishing Ltd

The efficient inclusion of rotation-induced inertia effects in a shaft-blisk assembly model using zero-speed modes

A successful design of rotating shaft-bladed disk (“blisk”) assemblies requires the facility to reliably predict the resonance speeds, which must be avoided during operation to avoid failure. Rotation-induced inertia effects (centrifugal stiffening, spin softening, Coriolis forces and gyroscopic moments) can cause significant variation of the modal frequencies with speed. A review of the state-of-the-art highlights the need for a methodology that can efficiently include all rotation-induced inertia effects in a generic shaft-blisk system. The novel contribution of this paper is a methodology to include such effects in a generic shaft-blisk system, using zero-speed finite element (FE) modal data, without the need for additional FE analysis at each speed, or the derivation of equations from first principles. This contribution is motivated by the need to upgrade an existing blisk simulator designed to generate blade tip timing (BTT) data for the development and validation of BTT algorithms. Rotational effects are added as discretised “external” excitations to the modal equations, which remain based on the zero-speed modes. The method is progressively validated on six examples, using results from the literature and commercial FE rotordynamics software, to demonstrate its accuracy and high efficiency of computation for both Campbell diagrams and forced response

Can the ileocecal valve point predict low back pain using manual muscle testing?

Background: According to some technique groups in chiropractic the ileocecal valve may malfunction and be associated with a large array of health problems that can lead to common chronic health issues prevalent in our society. Many tests commonly used in chiropractic are presumed to identify painful and/or dysfunctional anatomical structures, yet many have undemonstrated reliability. Despite this lack of evidence, they form the basis of many clinical decisions. One cornerstone procedure that is frequently used by chiropractors involves the use of manual muscle testing for diagnostic purposes not considered orthopaedic in nature. A point of the body referred to as the ileocecal valve point is said to indicate the presence of low back pain. This procedure is widely used in Applied Kinesiology (AK) and Neuro-Emotional Technique (NET) chiropractic practice. Objective: To determine if correlation of tenderness of the "ileocecal valve point" can predict low back pain in sufferers with and without low back pain. It was the further aim to determine the sensitivity and specificity of the procedure. Methods: One hundred (100) subjects with and without low back pain were recruited. Subjects first completed information about their pain status, then the practitioner performed the muscle testing procedure in a separate room. The practitioner provided either a yes or no response to a research assistant as to whether he had determined if the subject had back pain based on the muscle test procedure. Results: Of 67 subjects who reported low back pain, 58 (86.6%) reported a positive test of both low back pain and ICV point test. Of 33 subjects, 32 (97.0%) with no back pain positively reported no response to ICV point test. Nine (9) subjects (13.4%) reported false negative ICV tests and low back pain, and 1 subject (3%) reported a false positive response for ICV test and no low back pain. Conclusion: The majority of subjects with low back pain reported positive ileocecal valve testing, and all but one of the subjects without low back pain reported negative ileocecal valve testing. The application of ileocecal valve testing as a diagnostic measure of low back pain was found to have excellent measures of sensitivity, specificity and diagnostic competency. This study confirms that the use of this test within the limitations of this study is reliably associated with the presence of low back pain. Further testing is required to investigate all aspects of the diagnostic milieu commonly used by proponents of this form of diagnostic testing

Uncertainties in the calibration process of blade tip timing data against finite element model predictions

Blade stresses are determined from blade tip timing (BTT) data by relating the measured tip deflection to the stresses via Finite Element (FE) models. This process includes some uncertainties due to the following: 1) the shift in the equilibrium position of the blade tip due to steady deflection and/or movements, 2) the change in effective stiffness due to rotation-induced inertia, which affects the BTT-stress calibration factors, 3) the assumption of constant speed over a single revolution that is made in most of BTT algorithms, which is not appropriate for rapid speed rates. This study shows the effect of such uncertainties on the vibration measurement and blade stress estimations

REQUIREMENTS FOR CHIROPRACTORS INVOLVED AS OCCUPATIONAL HEALTH AND SAFETY CONSULTANTS IN AUSTRALIA

A literature review was conducted to determine significant factors for chiropractors progressing towards classification as an Occupational Health & Safety (OHS) consultant in Australia

Experimental validation of a novel smart electromechanical tuned mass damper beam device

This paper validates the novel concept of utilising piezoelectric vibration energy harvesting (PVEH) beams as a tuned mass damper (TMD) - which suppresses a particular vibration mode of a generic host structure over a broad band of excitation frequencies. The proposed device comprises a pair of bimorphs shunted by a resistor, capacitor and inductor connected in various alternative circuit configurations. A benchmark for the performance is established through Den Hartog's theory for the optimal damping of a classical TMD. Experimental results demonstrate that such optimal damping is equivalently generated by the PVEH effect for appropriately tuned circuitry. These results correlate reasonably well with the results of a theoretical analysis introduced in a previous paper. The proposed TMD beam device combines the relative advantages of the classical ('mechanical') TMD and the shunted piezoelectric patch ('electrical' vibration absorber), presenting the prospect of a functionally more readily-adaptable class of 'electromechanical' tuned vibration absorbers. Moreover, with further development, this dual PVEH/TMD beam device holds the potential of simultaneous energy storage. © 2013 Elsevier Ltd