bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of balance exercises on people with multiple sclerosis: a pilot study
Authors: Cattaneo D. , Jonsdottir J. , Zocchi M. , Regola A. 
Published: September 2007

Objective: To evaluate the effects of balance retraining in a sample of people with multiple sclerosis. Design: Randomized controlled trial. Setting: Rehabilitation unit. Subjects: A consecutive sample of 44 subjects was randomized into two experimental groups and one control group. The inclusion criteria were: ability to stand independently more than 30 seconds, ability to walk for 6 m. Interventions: Group 1 received balance rehabilitation to improve motor and sensory strategies. Group 2 received balance rehabilitation to improve motor strategy. Group 3 received treatments not specifically aimed at improving balance. Main outcome measure: Berg Balance Scale, Dynamic Gait Index and fall frequency were used to assess balance impairments. Dizziness Handicap Inventory and Activities-specific Balance Confidence were used to assess handicap and the level of balance confidence. Results: Frequency of falls post treatment was statistically different among groups (P = 0.0001); The Berg Balance Scale showed an overall statistically significant difference (P = 0.0008) among groups. Change pre—post scores were 6.7, 4.6 and 0.8 points for groups 1, 2 and 3. Dynamic Gait Index showed an overall near statistically significant difference among groups (P = 0.14), with change pre—post scores of 3.85, 1.6 and 1.75 points for groups 1, 2 and 3; after the exclusion of drop-outs a statistically significant difference was observed (P = 0.04). The self-administered tests (Activities-specific Balance Confidence and Dizziness Handicap Inventory) did not show clinically relevant improvements. Conclusions: Balance rehabilitation appeared to be a useful tool in reducing the fall rate and improving balance skills in subjects with multiple sclerosis. Exercises in different sensory contexts may have an impact in improving dynamic balance.
The role of fear-avoidance beliefs in patients with neck pain: relationships with current and future disability and work capacity
Authors: Lee Kwok-Chung , Chiu Thomas T.W. , Lam Tai-Hing 
Published: September 2007

Objectives: To investigate the relationship between fear-avoidance beliefs and future disability and work capacity in patients with neck pain. Design: A prospective observational study. Setting: Physiotherapy outpatient departments. Patients: One hundred and twenty patients with neck pain intensity sufficient to affect their work capacity. Interventions: Patients participated in either six-week conventional physiotherapy or an exercise training programme to test whether the type of treatment received by the patients together with other outcome measures affected the predictive power of fear-avoidance beliefs. Main outcome measures: Patients underwent examination of the active neck range of movements and neck muscle strength and completed the Fear-Avoidance Beliefs Questionnaire, the Northwick Park Neck Pain Questionnaire, the Medical Outcomes 36-Item Short-Form Health Survey and the 11-point pain numerical rating scale. These were assessed at the beginning and at week 6 of the rehabilitation programme. Patients' work capacity was assessed at week 6 and three months after the six-week rehabilitation programme. Results: Spearman's correlation coefficients between fear-avoidance beliefs and initial and week 6 disability levels were 0.47 and 0.48, respectively. Regression analysis showed that the fear-avoidance beliefs significantly improved the goodness of fit of the model for predicting week 6 disability levels and return to complete work capacity at week 6 and three months after the rehabilitation programme, even after controlling for the physical impairments, the health status, the pain intensity and the type of treatment received. Conclusions: The fear-avoidance beliefs factor is an important biopsychosocial variable in predicting future disability level and return to complete work capacity in patients with neck pain.
One session of whole body vibration increases voluntary muscle strength transiently in patients with stroke
Authors: Tihanyi Tekla Kornélia , Horváth Mónika , Fazekas Gábor , Hortobágyi Tibor , Tihanyi József 
Published: September 2007

Objective: To determine the effect of whole body vibration on isometric and eccentric torque and electromyography (EMG) variables of knee extensors on the affected side of stroke patients. Design: A randomized controlled study. Setting: A rehabilitation centre. Subjects: Sixteen patients (age 58.2 ± 9.4 years) were enrolled in an inpatient rehabilitation programme 27.2 ± 10.4 days after a stroke. Interventions: Eight patients were randomly assigned to the vibration group and received 20 Hz vibration (5 mm amplitude) while standing on a vibration platform for 1 minute six times in one session. Patients in the control group also stood on the platform but did not receive vibration. Main measures: Maximum isometric and eccentric torque, rate of torque development, root-mean-squared EMG, median frequency of vastus lateralis, and co-activation of knee flexors. Results: Isometric and eccentric knee extension torque increased 36.6% and 22.2%, respectively, after vibration (P < 0.05) and 8.4% and 5.3% in the control group. Vibration increased EMG amplitude 44.9% and the median frequency in the vastus lateralis by 13.1% (all P < 0.05) without changes in the control group (10.6% and 3.9%). Vibration improved the ability to generate mechanical work during eccentric contraction (17.5%). Vibration reduced biceps femoris co-activation during isometric (8.4%, ns) and eccentric (22.5%, P < 0.05) contraction. Conclusion: These results suggest that one bout of whole body vibration can transiently increase voluntary force and muscle activation of the quadriceps muscle affected by a stroke.
Is it possible to use the Structural Dimension Analysis of Motor Memory (SDA-M) to investigate representations of motor actions in stroke patients?
Authors: Braun Susy M. , Beurskens Anna J. , Schack Thomas , Marcellis Rik G. , Oti Kenneth C. , Schols Jos M. , Wade Derick T. 
Published: September 2007

Objective: To determine the feasibility of the Structural Dimension Analysis of Motor Memory (SDA-M), a method derived from sports psychology, in establishing the mental representations of complex movements in patients after stroke. Design: Case series of patients, with age-matched healthy controls. Setting: A rehabilitation nursing home. Subjects: Sixteen patients 3—26 weeks after their stroke, and 16 controls. Intervention: Each control had the SDA-M performed within a 10-day period. Each stroke patient had the SDA-M performed once. In the SDA-M the subject was asked to state for each of 10 actions involved in drinking from a cup whether it is functionally close to each of the other nine or not. Main measures: The raw data from the SDA-M were transformed through cluster analysis into Euclidean distances and tree diagrams to illustrate the internal representation of the action. Results: All subjects were able to perform the assessment. Healthy controls all had a similar set of Euclidean distances and tree diagrams that were `normal'. The tree diagrams remained very similar on the three occasions. Four stroke patients had tree diagrams that were `normal'. The remaining twelve had tree diagrams that differed greatly both from the `normal' and from each other, with much less clustering of actions. Patients with more severe stroke appeared to have more disordered tree diagrams. Conclusion: The Structural Dimension Analysis of Motor Memory (SDA-M) is a feasible method for investigating the mental representation of internal motor action plans in stroke patients, giving similar data in stable healthy people and revealing abnormal patterns in patients after stroke.
Diagnosis and treatment of depression following acquired brain injury: a comparison of practice in the UK and the Netherlands
Authors: Knottnerus Anne Margreet , Turner-Stokes Tabitha , van de Weg F.B. , Heijnen L. , Lankhorst G.J. , Turner-Stokes Lynne 
Published: September 2007

Objective: To describe and compare current practice in diagnosis and treatment of depression following acquired brain injury in two countries (UK and the Netherlands) which have different sets of guidelines. Setting and design: A cross-sectional survey of reported practice among rehabilitation physician members of the British and Dutch specialist societies. Methods: A 12-item postal questionnaire was sent to 496 rehabilitation physicians with two reminders: N = 353 (71%) responded, 146 of whom did not manage people with acquired brain injury, leaving 207 questionnaires for analysis (Netherlands N = 121, UK N = 86). Descriptive summary statistics were compiled. Categorical and dichotomous data were compared between the groups using chi-squared tests. Results: Sixty-seven (78%) of British respondents served a predominantly younger adult (65 years) population, compared with only 27 (22%) of the Dutch, who mainly treated patients of all ages. In line with their respective guidelines, more British respondents reported that they screened all acquired brain injury patients for depression (68/86 (79%) British versus 71/121 (59%) Dutch, P < 0.01), and used formal measures (37/68 (54%) versus 14/69 (20%), P < 0.001). They also took a more active role in treatment of depression: only 1 (1%) never used antidepressants, compared with 22 (18%) of Dutch respondents (P < 0.001). On the other hand, where antidepressants were prescribed, the Dutch respondents were more likely than the British to follow-up their patients (93/98 (95%) versus 67/84 (80%), P < 0.01). Conclusions: The survey demonstrates a broadly similar approach, but highlights some significant variance in practice between the two countries which may stem from differences in population and service provision as well as their respective guidelines.
Fast response aerodynamic probes for measurements in turbomachines
Authors: Brouckaert J. F. 
Published: September 2007

The present paper concentrates on the use of single- and multi-sensor pressure probes designed for the accurate measurement of unsteady total pressure and flow angle for turbo-machinery applications. Fast response pressure probes have the advantage of offering a high analogue bandwidth, a high signal-to-noise ratio, and a good reliability and robustness as compared to hot-wire techniques for instance. In addition to the magnitude and direction of the flow velocity vector, aerodynamic probes also indicate the total and static pressure as time-resolved quantities. Appropriate data processing then allows to retrieve not only the steady, but also the periodic and random components of the measured variables. The design of several single or multi-sensor probes is briefly described in this paper. These probes have been developed, manufactured and fully calibrated at the von Karman Institute to be used in laboratory and in industry environments over the last 8 years. The main objective of this contribution is to address some examples of applications but focus on the capabilities of the technique rather than on flow field analysis.
Influence of external geometrical modifications on the flow behaviour of a rotor-stator system: Numerical and experimental investigation
Authors: Debuchy R , Gatta S. Della. , D'Haudt E , Bois G , Martelli F 
Published: September 2007

Earlier experimental and numerical studies have shown the sensitiveness of flow behaviour inside a rotating disc system due to peripheral geometry adjustments. In an opened annular cavity without any superimposed flow, velocity, and pressure levels are strongly affected by a very weak variation of the γ parameter, based on the radii difference between the two discs. The aim of the present work is to improve knowledge of the influence of this parameter with the help of numerical simulations performed with the CFD Fluent code and experimental results carried out by hot-wire anemometry and three-holes pressure probe. At the periphery, centrifugal effects of the rotor drive the fluid out of the cavity, imposing flow compensation on the stator side. Peripheral geometry influences the source of the inlet fluid and the inlet/outlet area ratio: these are two major elements conditioning the pre-swirl of the fluid at the periphery, which seems to control the flow behaviour inside the cavity. One major consequence is that the well-known Batchelor type flow is not always encountered in the inner part of the cavity: it may gradually appear over a range of the λ parameter specific to geometrical conditions of the inlet.
Numerical simulation of the flow in a Pelton turbine using the meshless method smoothed particle hydrodynamics: A new simple solid boundary treatment
Authors: Marongiu J. C. , Leboeuf F , Parkinson E 
Published: September 2007

Meshless methods are getting more and more popular in order to numerically simulate physical phenomena where an interface appears and plays an important role. Thanks to its fully Lagrangian formalism, the smoothed particle hydrodynamics method (SPH) is hence well suited to simulate free surface flows. The Pelton turbine is an hydraulic turbomachinery whose flow is challenging to simulate because of the complex rotating geometry, the free surface and the interaction between the runner and the casing. The work presented here aims at adapting SPH to simulate such a flow. The standard SPH model has first been successfully used to prove the capacity of the method in order to simulate flows in Pelton turbines. As the prediction of the pressure field on the bucket's surface is a key issue, a new simple model for the treatment of solid boundary conditions is proposed. Simulations of industrial test cases, including a complete rotating runner, are finally shown.
Tip clearance effect on high-pressure compressor stage matching
Authors: Domercq O , Escuret J-F 
Published: September 2007

Tip clearance flows have a major impact on both performance and stability of high-pressure compressors (HPC). The purpose of this paper is to underline how tip clearance variations affect the matching of compressor stages, hence modifying the efficiency and stall margin of the compressor. The practical application covered by the scope of this article is a modern highly loaded HPC dedicated to civil aircraft propulsion. The first part of the paper gives a very simple overview of stagewise matching in multistage compressors. Also, this part introduces the subject of the impact of tip clearance on stage matching. The second part of the paper illustrates the effect of increased rear block clearances on performance and stability, using some available experimental data. Finally, it is shown that three-dimensional multi-stage calculations can predict the effect of tip clearance variations on stage pressure-rise characteristics and on stage matching. This validated numerical tool therefore allows the aerodynamic design to be adjusted to the range of in-service clearances, thus providing a more robust compressor design.
Fair Payments for Efficient Allocations in Public Sector Combinatorial Auctions
Authors: Day Robert W. , Raghavan S. 
Published: September 2007

Motivated by the increasing use of auctions by government agencies, we consider the problem of fairly pricing public goods in a combinatorial auction. A well-known problem with the incentive-compatible Vickrey-Clarke-Groves (VCG) auction mechanism is that the resulting prices may not be in the core. Loosely speaking, this means the payments of the winners could be so low, that there are bidders who would have been willing to pay more than the payments of the winning bidders. Clearly, this “unfair” outcome is unacceptable for a public sector auction. Recent advances in auction theory suggest that combinatorial auctions resulting in efficient outcomes and bidder-Pareto-optimal core payments offer a viable practical alternative to address this problem. This paper confronts two critical issues facing the bidder-Pareto-optimal core payment. First, motivated to minimize a bidder's ability to benefit through strategic manipulation (through collusive agreement or unilateral action), we demonstrate the strength of a mechanism that minimizes total payments among all such auction outcomes, narrowing the previously broad solution concept. Second, we address the computational difficulties of achieving these outcomes with a constraint-generation approach, promising to broaden the range of applications for which bidder-Pareto-optimal core pricing achieves a comfortably rapid solution.
Should Price Increases Be Targeted?—Pricing Power and Selective vs. Across-the-Board Price Increases
Authors: Krishna Aradhna , Feinberg Fred M. , Zhang Z. John 
Published: September 2007

Firms in many industries experience protracted periods of pricing power, the ability to successfully enact price increases. In these situations, firms must decide not only whether to raise prices, but to whom. Specifically, in a competitive context, they must determine whether it is more profitable to increase prices across-the-board or to a specific segment of their customer base. While selective price decreases are ubiquitous in practice (e.g., better deals to potential new customers by phone carriers; better deals to current customers by various magazines), to our knowledge selective price increases are relatively rare. We illustrate the benefits of targeted price increases, and, as such, we expand the repertoire of firms' promotional policies. To that end, we explore a scenario where two competing firms must decide whether to increase prices to the entire market or only to a specific segment. Targeted price increases (TPI), i.e., being offered an unchanged price (selectively) when others are subject to price increases, can be offered to Loyals (those who bought from the firm in the previous period) or Switchers (those who did not). The effects of TPIs are estimated through a laboratory experiment and an associated stochastic model, each allowing for both rational (Loyalty, Switching) and behaviorist (Betrayal, Jealousy) effects. We find that TPIs can indeed yield beneficial results (greater retention for Loyals or greater attraction of Switchers) and greater profits in certain circumstances. Results for TPI are additionally benchmarked against those for targeted price decreases and are found to differ. The range of effects stemming from the experiment can be used in a competitive analysis to yield equilibrium strategies for the two firms. In this case, we find that—depending on the magnitude of the price increase, market shares of the two firms, and price knowledge across consumer segments—a firm may wish to embrace targeted price increases in some situations, to institute across-the-board price increases in others, and to not enact any price increases in still others. We show that a firm can sacrifice considerable profit if it settles on a suboptimal pricing strategy (e.g., wrongly instituting an across-the-board increase), favors the wrong segment (e.g., Switchers instead of Loyals), or ignores “behaviorist” effects (Betrayal or Jealousy).
Welding of Thermoplastic Roofing Membranes Subjected to Different Conditioning Procedures
Authors: Graveline Stanley 
Published: September 2007

Abstract
The use of thermoplastic roofing membranes has grown dramatically over the past years. This has occurred for a number of reasons including the proven track record of some products, the move to light colored “cool” materials, and the variety of systems available. A key benefit of thermoplastic membranes is the ability to hot air weld their seams, creating a permanent seal. As these single-ply membranes are installed in a one-ply configuration, a properly executed seam is critical to their long-term performance. Welding properties of membranes from five different manufacturers of thermoplastics: two polyvinyl chloride (PVC), two thermoplastic olefins (TPO), and one KEE (ketone ethylene ester) were studied. All materials were welded at twelve different combinations of welding temperature and speed. Each of these “welding windows” was completed with material as received, after 4 days immersed in water and after 30 days of exposure to severe soiling. Finished welds were assessed by peel testing in a tensile test apparatus. Differences in welding properties of specific materials and the generic types of products were evaluated, including sensitivity to changes in weld parameters, the effectiveness of manufacturer recommended cleaning/seam preparation, as well as the impact of the conditioning processes on weld quality. Integrating a previous study by others, a weld safety factor concept was developed which is a useful metric for assessing weld quality. This work demonstrated the need for clear, product specific welding guidelines for both new materials and for roof membranes exposed to the elements so as to ensure a proper weld.
'Black, Brown and Beige' and the politics of Signifyin(g)
Authors: Burrows George 
Published: September 2007

Duke Ellington has attracted critical attention from across the whole cultural spectrum and yet he is in many ways a problematic figure who remains misunderstood. This paper draws on Michel Foucault’s consideration of polemics to illuminate critical strategies that have been directed towards Ellington. It explores how we might move beyond polemics and reinterpret Ellington as an artist ‘beyond category’ by considering his most controversial and ambitious work, Black, Brown and Beige, as a Signfyin(g) text. Ellington’s unique working practices, the special sound world of his band, his declared tendency to ‘say things without saying them’ and his view of himself as a black bandleader-composer of ‘Negro folk music’ all help inform a reassessment of the work in light of recent developments in African-American critical thinking and to establish the political legacy of Ellington’s cultural positioning as a trickster figure critiquing polemics by slipping between, about or around musical categories.
Failure to fuse
Authors: Brennan Matt 
Published: September 2007

Festivals play a central role in popular music mythology. In 1969, the Newport Jazz Festival made headlines when producer George Wein controversially announced his intention to openly incorporate rock acts, including Sly and the Family Stone and Led Zeppelin, into the jazz festival. Newport 1969 is retrospectively represented as a symbol of the problems of integrating jazz and rock, but a critical examination of the festival and its coverage clearly illustrates how distinctions between jazz and rock—and jazz and rock audiences, for that matter—are socially constructed. This article will reconsider the importance of Newport 1969 by revisiting debates occurring in the pages of Down Beat, Rolling Stone, Jazz and Pop, and other music journalism during 1969 which discussed the merits of a merger between jazz and rock, and proposes that Newport 1969 was a watershed that exposed the key tensions in the emerging culture war between the two genres.