11,266 research outputs found
Disc disease: A summary and review
A review of the etiology, clinical, radiological and laboratory presentation, differential diagnosis and management goals of disc disease is presented.
Keywords: Disc disease, disc herniation, disc bulge, disc prolapse, disc lesion, internal disc disruption, annular tear, chemical radiculitis, low back pain, sciatica, chiropracti
Openness, Globalization and Economic Growth: Empirical Evidence from Cote d´Ivoire, 1969-2002
The purpose of this paper is to examine the relationships between openness, globalization on economic growth in Côte d’Ivoire which adopted the openness of its economy as the basic way for development at the beginning of its economic history in 1960. Using a three-variable vector autoregressive (VAR) model, we find that the three variables are tied together in the long-run. Although a positive effect of openness on growth is observed in the short-run, both increasing openness and globalisation do not have positively contributed to the long-run economic growth of this country, a finding that is in the opposite of the prediction of the new growth theory about the potential long-run effects of trade on growth.Openness, Globalization, Growth, Cointegration, Causality, Impulse response
Carbohydrate Mouth Rinse Improves 1.5 h Run Performance: Is There a Dose-Effect?
There is a substantial body of recent evidence showing ergogenic effects of carbohydrate (CHO) mouth rinsing on endurance performance. However, there is a lack of research on the dose-effect and the aim of this study was to investigate the effect of two different concentrations (6% and 12% weight/volume, w/v) on 90 minute treadmill running performance. Seven active males took part in one familiarization trial and three experimental trials (90-minute self-paced performance trials). Solutions (placebo, 6% or 12% CHO-electrolyte solution, CHO-E) were rinsed in the mouth at the beginning, and at 15, 30 and 45 minutes during the run. The total distance covered was greater during the CHO-E trials (6%, 14.6 ± 1.7 km; 12%, 14.9 ± 1.6 km) compared to the placebo trial (13.9 ± 1.7 km, P 0.05). There were no between trial differences (P > 0.05) in ratings of perceived exertion (RPE) and feeling or arousal ratings suggesting that the same subjective ratings were associated with higher speeds in the CHO-E trials. Enhanced performance in the CHO-E trials was due to higher speeds in the last 30 minutes even though rinses were not provided during the final 45 minutes, suggesting the effects persist for at least 20-45 minutes after rinsing. In conclusion, mouth rinsing with a CHO-E solution enhanced endurance running performance but there does not appear to be a dose-response effect with the higher concentration (12%) compared to a standard 6% solution
Low streamflow in the Myakka River Basin Area in Florida
The Sarasota-Manatee area is a water-short area and the study
was undertaken in 1963 in order to determine the storage capability
and discharge rates of the Myakka water shed. It was found
that many of the streams of the water shed were virtually dry
during part of every year. However, the basins of the Myakka
lakes, through which the river flows offer some storage potential,
that if properly developed would provide a continuance drift of
about seven million gallons of water per day of good quality water
that would be high in color and temperature upon occasion. With
reasonable treatment some of this water could be used to meet
the present needs of the rapidly expanding coastal areas. (PDF contains 40 pages.
The More Cooperation, the More Competition? A Cournot Analysis of the Benefits of Electric Market Coupling
Market coupling in Belgian and Dutch markets would permit more efficient use of intercountry transmission, 1) by counting only net flows against transmission limits, 2) by improving access to the Belgian market, and 3) by eliminating the mismatch in timing between interface auctions and the energy spot market. A Cournot market model that accounts for the region’s transmission pricing rules and limitations is used to simulate market outcomes with and without market coupling. This accounts for 1) and 2). Market coupling improves social surplus in the order of 108 €/year, unless it encourages the largest producer in the region to switch from a price-taking strategy in Belgium to a Cournot strategy due to a perceived diminishment of the threat of regulatory intervention. Benefit to Dutch consumers depends on the behavior of this company. The results illustrate how large-scale oligopoly models can be useful for assessing market integration.Electric power, Electric transmission, Liberalization, Oligopoly, Complementarity models, Computational models, Netherlands, Belgium, France, Germany, Market Coupling
Recommended from our members
Survey of Galveston Public Schools-Section I. Buildings and Equipment, by J.H. Shelby-Section II. Finance, by B.F. Pittenger- Section III. Child Accounting, Curriculum, and Teachers' Salaries, by H.T. Manuel
Delineating inflammatory and mechanical sub-types of low back pain: a pilot survey of fifty low back pain patients in a chiropractic setting
Background
An instrument known as the Mechanical and Inflammatory Low Back Pain (MAIL) Scale was drafted using the results of a previous expert opinion study. A pilot survey was conducted to test the feasibility of a larger study designed to determine the MAIL Scale's ability to distinguish two potential subgroups of low back pain: inflammatory and mechanical.
Methods
Patients with a primary complaint of low back pain (LBP) presenting to chiropractic clinics in Perth, Western Australia were asked to fill out the MAIL Scale questionnaire. The instrument's ability to separate patients into inflammatory and mechanical subgroups of LBP was examined using the mean score of each notional subgroup as an arbitrary cut-off point.
Results
Data were collected from 50 patients. The MAIL Scale did not appear to separate cases of LBP into the two notionally distinct groups of inflammatory (n = 6) or mechanical (n = 5). A larger "mixed symptom" group (n = 39) was revealed.
Conclusions
In this pilot study the MAIL Scale was unable to clearly discriminate between what is thought to be mechanical and inflammatory LBP in 50 cases seen in a chiropractic setting. However, the small sample size means any conclusions must be viewed with caution. Further research within a larger study population may be warranted and feasible
The test-retest reliability of centre of pressure measures in bipedal static task conditions - A systematic review of the literature
Summary of background data: The analysis of centre of pressure (COP) excursions is used as an index of postural stability in standing. Conflicting data have been reported over the past 20 years regarding the reliability of COP measures and no standard procedure for COP measure use in study design has been established. Search methods: Six online databases (January 1980 to February 2009) were systematically searched followed by a manual search of retrieved papers. Results: Thirty-two papers met the inclusion criteria. The majority of the papers (26/32, 81.3%) demonstrated acceptable reliability. While COP mean velocity (mVel) demonstrated variable but generally good reliability throughout the different studies (r= 0.32-0.94), no single measurement of COP appeared significantly more reliable than the others. Regarding data acquisition duration, a minimum of 90 s is required to reach acceptable reliability for most COP parameters. This review further suggests that while eyes closed readings may show slightly higher reliability coefficients, both eyes open and closed setups allow acceptable readings under the described conditions (r≥0.75). Also averaging the results of three to five repetitions on firm surface is necessary to obtain acceptable reliability. A sampling frequency of 100. Hz with a cut-off frequency of 10. Hz is also recommended. No final conclusion regarding the feet position could be reached. Conclusions: The studies reviewed show that bipedal static COP measures may be used as a reliable tool for investigating general postural stability and balance performance under specific conditions. Recommendations for maximizing the reliability of COP data are provided
Locational-based Coupling of Electricity Markets: Benefits from Coordinating Unit Commitment and Balancing Markets
We formulate a series of stochastic models for committing and dispatching electric generators subject to transmission limits. The models are used to estimate the benefits of electricity locational marginal pricing (LMP) that arise from better coordination of day-ahead commitment decisions and real-time balancing markets in adjacent power markets when there is significant uncertainty in demand and wind forecasts. The unit commitment models optimise schedules under either the full set of network constraints or a simplified net transfer capacity (NTC) constraint, considering the range of possible real-time wind and load scenarios. The NTC-constrained model represents the present approach for limiting day-ahead electricity trade in Europe. A subsequent redispatch model then creates feasible real-time schedules. Benefits of LMP arise from decreases in expected start-up and variable generation costs resulting from consistent consideration of the full set of network constraints both day-ahead and in real-time. Meanwhile, using LMP to coordinate adjacent balancing markets provides benefits because it allows intermarket flow schedules to be adjusted in real-time in response to changing conditions. These models are applied to a stylised four-node network, examining the effects of varying system characteristics on the magnitude of the locational-based unit commitment benefits and the benefits of intermarket balancing. Although previous www.eprg.group.cam.ac.uk EPRG WORKING PAPER studies have examined the benefits of LMP, these usually examine one specific system, often without a discussion of the sources of these benefits, and with simplifying assumptions about unit commitment.
We conclude that both categories of benefits are situation dependent, such that small parameter changes can lead to large changes in expected benefits. Although both can amount to a significant percentage of operating costs, we find that the benefits of balancing market coordination are generally larger than the unit commitment benefits
Can We See the Shape of the Universe?
This is a written version of a talk given at the Fifth Friedmann Seminar on
recent work in Observational Cosmic Topology done in partial collaboration with
Armando Bernui. We address three relevant questions related to the search for
the size and shape of our Universe: (i) How do the actual observation of
multiple images of certain cosmic objects, e.g. galaxy clusters, constrain the
possible models for the shape of our Universe?, (ii) What kind of predictions
can be done once a pair of cosmic objects have been identified to be
topological images related by a translation?, and (iii) Is it possible to
determine if two regions of space are topologically identified, even when
distortions on the distributions of cosmic sources due to observational
limitations are not negligible? We give examples answering the first two
questions using the suggestion of Roukema and Edge that the clusters RXJ
1347.5-1145 and CL 09104+4109 might be topological images of the Coma cluster.
For the third question, we suggest a method based on the analysis of PSH's
noise correlations which seems to give a positive answer.Comment: 6 pages, latex2e, contribution to the 5th Alexander Friedmann Seminar
on Gravitation and Cosmology, to appear in Int. J. Mod. Phys. A (2002).
Macros: ws-ijmpa.cl
- …