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The air‐water exchange of trace gases such as CO2 is usually parameterized in terms of a gas transfer velocity, which can be derived from direct measurements of the air‐sea gas flux. The transfer velocity of poorly soluble gases is driven by near‐surface ocean turbulence, which may be enhanced or suppressed by the presence of sea ice. A lack of measurements means that air‐sea fluxes in polar regions, where the oceanic sink of CO2 is poorly known, are generally estimated using open‐ocean transfer velocities scaled by ice fraction. Here, we describe direct determinations of CO2 gas transfer velocity from eddy covariance flux measurements from a mast fixed to ice adjacent to a sea‐ice lead during the summer‐autumn transition in the central Arctic Ocean. Lead water CO2 uptake is determined using flux footprint analysis of water‐atmosphere and ice‐atmosphere flux measurements made under conditions (low humidity and high CO2 signal) that minimize errors due to humidity cross‐talk. The mean gas transfer velocity is found to have a quadratic dependence on wind speed: k660 = 0.179 U102, which is 30% lower than commonly used open‐ocean parameterizations. As such, current estimates of polar ocean carbon uptake likely overestimate gas exchange rates in typical summertime conditions of weak convective turbulence. Depending on the footprint model chosen, the gas transfer velocities also exhibit a dependence on the dimension of the lead, via its impact on fetch length and hence sea state. Scaling transfer velocity parameterizations for regional gas exchange estimates may therefore require incorporating lead width data. Plain Language Summary: Polar oceans absorb large amounts of carbon dioxide from the atmosphere, but there is a lot of uncertainty over exactly how much is taken up. The amount the oceans absorb depends on both the concentration of carbon dioxide in the water, and the rate of gas exchange between the ocean and the atmosphere. This rate itself depends mostly on wind speed. In sea ice‐regions, which even in winter have some areas of open water, the gas exchange rate is often estimated by using an ocean gas exchange rate, multiplied by the fraction of the sea‐ice area, that is, open water. However, there are very few measurements of the gas exchange rate in sea‐ice areas, and there is an on‐going debate about whether the sea ice itself increases or decreases the exchange rate. Here, direct measurements of the gas exchange rate were made in an area of water surrounded by sea ice in the Arctic during summer and the beginning of autumn. The measured gas exchange rate was lower than typical ocean rates, suggesting that the absorption of carbon dioxide by polar oceans has previously been overestimated. Key Points: CO2 uptake in lead waters is determined using water‐atmosphere and ice‐atmosphere flux measurements from an on‐ice mastThe wind‐speed dependent gas transfer velocity in the lead is suppressed by 30% relative to the open oceanDependent on choice of footprint model, k varies with fetch, hence polar ocean carbon uptake estimates should incorporate lead width data [ABSTRACT FROM AUTHOR]

Simultaneous measurements of near-surface aerosol and bubble spectra were made during five buoy deployments in the open ocean of the North Atlantic and used to estimate aerosol fluxes per unit area of whitecap. The measurements were made during two cruises as part of the SEASAW project, a UK contribution to the international SOLAS program. The mean bubble number concentrations for each deployment are in broad agreement with other open ocean spectra and are consistently one to two orders of magnitude lower than previous laboratory and surf zone studies. This suggests that the aerosol fluxes estimated above open ocean whitecaps will differ to those from over the surf zone and laboratory whitecaps due to the differences in the size and number of bursting bubbles. Production fluxes per unit area of whitecap are estimated from the mean aerosol concentration for each buoy deployment. They are found to increase with wind speed, and span the range of values found by previous laboratory and surf-zone studies for particles with radius at 80% humidity, R80 < 1 ìm, but to drop off more rapidly with increasing size for larger particles. A possible cause of this difference in behavior is the significant difference in bubble spectra. Estimates of the mean sea spray flux were made by scaling the whitecap production fluxes with in-situ estimates of whitecap fraction. The sea spray fluxes are also compared with simultaneous individual eddy covariance flux estimates made during the cruise, and with a sea spray source function derived from them. [ABSTRACT FROM AUTHOR]

Data from platforms, research vessels and merchant ships are used to estimate ocean CO2 uptake via parameterisations of the gas transfer velocity (k) and measurements of the difference between the partial pressures of CO2 in the ocean (pCO2 sw) and atmosphere (pCO2 atm) and of wind speed. Gas transfer velocities estimated using wind speed dependent parameterisations may be in error due to air flow distortion by the ship's hull and superstructure introducing biases into the measured wind speed. The effect of airflow distortion on estimates of the transfer velocity was examined by modelling the airflow around the three-dimensional geometries of the research vessels Hakuho Maru and Mirai, using the Large Eddy Simulation code GERRIS. For airflows within ±45° of the bow the maximum bias was +16%. For wind speed of 10 m s-1 to 15 m s-1, a +16% bias in wind speed would cause an overestimate in the calculated value of k of 30% to 50%, depending on which k parameterisation is used. This is due to the propagation of errors when using quadratic or cubic parameterisations. Recommendations for suitable anemometer locations on research vessels are given. The errors in transfer velocity may be much larger for typical merchant ships, as the anemometers are generally not as well-exposed as those on research vessels. Flow distortion may also introduce biases in the wind speed dependent k parameterisations themselves, since these are obtained by relating measurements of the CO2 flux to measurements of the wind speed and the CO2 concentration difference. To investigate this, flow distortion effects were estimated for three different platforms from which wind speed dependent parameterisations are published. The estimates ranged from -4% to +14% and showed that flow distortion may have a significant impact on wind speed dependent parameterisations. However, the wind biases are not large enough to explain the differences at high wind speeds in parameterisations which are based on eddy covariance and deliberate tracer methods. [ABSTRACT FROM AUTHOR]

Data from research vessels and merchant ships are used to estimate ocean CO2 uptake via parameterizations of the gas transfer velocity (k) and measurements of the difference between the concentration of CO2 in the ocean (pCO2sw) and atmosphere (pCO2atm) and of wind speed. Gas transfer velocities estimated using wind speed dependent parameterisations may be in error due to air flow distortion by the ship's hull and superstructure introducing biases into the measured wind speed. The effect of airflow distortion on estimates of the transfer velocity was examined by modelling the airflow around the three-dimensional geometries of the research vessels Hakuho Maru and Mirai, using the Large Eddy Simulation code GERRIS. For airflows within ±45° of the bow the maximum bias was +16%. For wind speed of 10 m s-1 to 15 m s-1, a +16% bias in wind speed would cause an overestimate in the calculated value of k of 30% to 50%, depending on which k parameterisation is used. This is due to the propagation of errors when using quadratic or cubic parameterizations. Recommendations for suitable anemometer locations on research vessels are given. The errors in transfer velocity may be much larger for typical merchant ships, as the anemometers are generally not as well-exposed as those on research vessels. Flow distortion may also introduce biases in the wind speed dependent k parameterizations themselves, since these are obtained by relating measurements of the CO2 flux to measurements of the wind speed and the CO2 concentration difference. To investigate this, flow distortion effects were estimated for three different platforms from which wind speed dependent parameterizations are published. The estimates ranged from -4% to +14% and showed that flow distortion may have a significant impact on wind speed dependent parameterizations. However, the wind biases are not large enough to explain the differences at high wind speeds in parameterizations which are based on eddy covariance and deliberate tracer methods. [ABSTRACT FROM AUTHOR]

The article discusses the study that determines the effectiveness of acetaminophen, as compared to celecoxib, for treating degenerative joint diseases. The patients received sustained-release paracetamol, sustained-release celecoxib or placebo. They are those with a clinical diagnosis of degenerative joint disease for at least a month, and are candidates for long-term therapy. Based on observations, acetaminophen and celecoxib are indistinguishable in improving pain, stiffness, and function in patients with clinically diagnosed degenerative joint disease. However, acetaminophen is considered to be the first the drug of first choice, since it is less expensive and with fewer safety concerns.

Background: Prolotherapy involves repeated injections of irritant solutions to strengthen lumbosacral ligaments and reduce some types of chronic low-back pain; spinal manipulation and exercises are often used to enhance its effectiveness., Objectives: To determine the efficacy of prolotherapy in adults with chronic low-back pain., Search Strategy: We searched CENTRAL 2006, Issue 3 and MEDLINE, EMBASE, CINAHL, and AMED from their respective beginnings to October 2006, with no restrictions on language, and consulted content experts., Selection Criteria: We included randomised (RCT) and quasi-randomised controlled trials (QRCT) that compared prolotherapy injections to control injections, alone or in combination with other treatments, which measured pain or disability before and after the intervention., Data Collection and Analysis: Two review authors independently selected the trials and assessed methodological quality. Intervention protocols varied from study to study, making meta-analysis impossible., Main Results: We identified five high quality studies with a total of 366 participants. All measured pain or disability levels at six months, and four measured the proportion of participants reporting a greater than 50% reduction in pain or disability scores. Three randomized controlled trials (206 participants) found that prolotherapy injections alone are no more effective than control injection for chronic low-back pain and disability. At six months, there was no difference between groups in mean pain or disability scores (2 RCTs; 184 participants) and no difference in proportions who reported over 50% improvement in pain or disability (3 RCTs; 206 participants). These trials could not be pooled due to clinical heterogeneity. Two RCTs (160 participants) found that prolotherapy injections, given with spinal manipulation, exercise, and other therapies, are more effective than control injections for chronic low-back pain and disability. At six months, one study reported a significant difference between groups in mean pain and disability scores, whereas the other study did not. Both studies reported a significant difference in the proportion of individuals who reported over 50% reduction in disability or pain. Co-interventions confounded interpretation of results and clinical heterogeneity in the trials prevented pooling., Authors' Conclusions: There is conflicting evidence regarding the efficacy of prolotherapy injections for patients with chronic low-back pain. When used alone, prolotherapy is not an effective treatment for chronic low-back pain. When combined with spinal manipulation, exercise, and other co-interventions, prolotherapy may improve chronic low-back pain and disability. Conclusions are confounded by clinical heterogeneity amongst studies and by the presence of co-interventions.

Background: Prolotherapy is an injection-based treatment for chronic low-back pain. Proponents of prolotherapy suggest that some back pain stems from weakened or damaged ligaments. Repeatedly injecting them with irritant solutions is believed to strengthen the ligaments and reduce pain and disability. Prolotherapy protocols usually include co-interventions to enhance the effectiveness of the injections., Objectives: To determine the efficacy of prolotherapy injections in adults with chronic low-back pain., Search Strategy: We searched CENTRAL (2004, issue 1), MEDLINE, EMBASE, CINAHL and Science Citation Index from their respective beginnings to January 2004, with no restrictions on language. We consulted content experts to ensure we had not missed any references., Selection Criteria: Randomised and quasi-randomised controlled trials comparing prolotherapy injections to control injections, either alone or in combination with other treatments, were included. Studies had to include measures of pain and disability before and after the intervention., Data Collection and Analysis: Two reviewers independently selected the trials and assessed them for methodological quality. Treatment and control group protocols varied from study to study, making meta-analysis impossible., Main Results: We included four high quality studies with a total of 344 participants. All trials measured pain and disability levels at six months, three measured the proportion of participants reporting a greater than 50% reduction in pain or disability scores from baseline to six months.Two studies showed significant differences between the treatment and control groups for those reporting over 50% reduction in pain or disability. Their results could not be pooled. In one, co-interventions confounded interpretation of results; in the other, there was no significant difference in mean pain and disability scores between the groups. In the third study, there was little or no difference between groups in the number of individuals who reported over 50% improvement in pain and disability. The fourth study reporting only mean pain and disability scores showed no differences between groups., Reviewers' Conclusions: There is conflicting evidence regarding the efficacy of prolotherapy injections in reducing pain and disability in patients with chronic low-back pain. Conclusions are confounded by clinical heterogeneity amongst studies and by the presence of co-interventions. There was no evidence that prolotherapy injections alone were more effective than control injections alone. However, in the presence of co-interventions, prolotherapy injections were more effective than control injections, more so when both injections and co-interventions were controlled concurrently.

Background: Spinal signs found in association with atypical chest and abdominal pain may suggest the pain is referred from the thoracic spine. However, the prevalence of such signs in these conditions has rarely been compared with that in those without pain. In this study, the prevalence of spinal signs and dysfunction in patients with back, chest and abdominal pain is compared with that in pain free controls. The aim of the study is to determine the significance of spinal findings in patients with such pain., Methods: A general practitioner blinded to the patients' histories performed a cervical and thoracic spinal examination on general practice patients with back, chest and/or abdominal pain and on controls without pain. Thoracic intervertebral dysfunction was diagnosed on the basis of movement and palpation findings., Results: Seventy-three study patients plus 24 controls, were examined. For cervical spinal signs, pain in the back, chest and/or abdomen was associated with pain with active movements and overpressure at end range and with loss of movement range. For thoracic spinal signs, this association held for pain with active movements and overpressure, but not with loss of movement range. The prevalence of thoracic intervertebral dysfunction was 25.0% in controls, 65.5% with chest/abdominal pain, 72.0% with back pain and 79.0% with back pain with chest/abdominal pain. This prevalence was higher with chest pain than with abdominal pain., Conclusions: The results show an association, but not a causal link between thoracic intervertebral dysfunction and atypical chest/abdominal pain. A spinal examination should be performed routinely assessing these conditions. The minimum examination for the detection of intervertebral dysfunction is testing for pain with spinal movements and palpation for tenderness. The interpretation of positive signs requires knowledge of their prevalence in pain free controls and in patients with visceral disease.

Objective: To pilot a single-patient trials (SPTs) service in general practice, designed to improve decision-making about long-term medications for chronic conditions., Design: 12-week within-patient, randomised, double-blind, placebo-controlled, crossover comparison of ibuprofen with paracetamol for osteoarthritis, involving three pairs of two-week treatment periods for each participating patient., Setting and Patients: Patients attending an academic general practice with a clinical diagnosis of osteoarthritis, with pain of at least a month's duration severe enough to warrant consideration of long-term non-steroidal anti-inflammatory drug (NSAID) use., Main Outcome Measures: Pain and stiffness; measures of overall arthritis compared with previous fortnight; preference for NSAID at the end of each two-week treatment period; use of escape analgesia; side effects; and management changes as a result of the SPTs., Results: Eight of 14 patients completed SPTs. One was a clear responder to NSAIDs, five were non-responders, and two were indefinite. Of the five who were using NSAIDs' before the SPT, two continued and three ceased using them. Clinically useful information assisted decision-making for all eight participants. Medication management changed for six., Conclusions: Single-patient trials can be successfully implemented in general practice and might be a valuable method for GPs to identify patients who respond to medication for chronic stable conditions such as osteoarthritis, in which individual response to medication is variable.

This paper describes the use of standardized patient interviews as a means of assessing the consulting skills of fifth year medical students studying general practice. Interviews are restricted to a duration of 9 minutes and focus on either diagnostic or management tasks. Volunteers are trained to play standardized roles depicting common general practice presentations. A detailed marksheet has been developed to increase inter-examiner reliability, discourage global marking and incorporate a patient assessment of the student. Issues of reliability, validity and security in this form of assessment are discussed.

Aim: A double-blind, randomised clinical trial was conducted in Queensland general practices to evaluate the efficacy of oral doses of trimethoprim-sulfamethoxazole (cotrimoxazole) as an adjunct to Kenacomb ointment in the treatment of acute diffuse otitis externa., Method: One hundred and five patients with otitis externa agreed to enter the trial; 13 of these had bilateral otitis externa. Six symptoms and signs of otitis externa were rated on a scale of 1 (none) to 5 (severe) and then the scores were averaged to give an index of severity. Swabs from all infected ears were cultured and then the patients were treated with Kenacomb ointment. Patients were randomly assigned to take a five-day course of either oral cotrimoxazole or an oral placebo and were reassessed on Days 2-4 and Days 5-6 after presentation., Results: The mean duration (+/- standard deviation) of ear pain from the first visit for the cotrimoxazole and placebo groups was 3.1 (+/- 1.5) days and 3.1 (+/- 1.7) days respectively. The mean severity indices (+/- standard deviation) for these groups on presentation were 2.33 (+/- 0.59) and 2.37 (+/- 0.57). The respective reductions in these scores by the second visit were 0.72 and 0.69 and by the third visit 1.10 and 1.05. The principle pathogen isolated was Pseudomonas aeruginosa., Conclusion: This suggests that oral cotrimoxazole is unlikely to be useful as an adjunct to Kenacomb ointment in the treatment of mild to moderate otitis externa.

Breast self-examination (BSE) and medical breast examination practices were studied in a group of 1,103 women without diagnosed breast cancer, randomly sampled to conform in age and social status with breast cancer cases from the population of Brisbane, Australia between 1981 and 1985. Relationships between these practices and sociodemographic factors, breast cancer risk indicators, health related behaviors and source of knowledge about BSE were analyzed. Overall, 63% of women reported performing BSE. BSE was practiced frequently (monthly or more). BSE frequency was only weakly associated with breast cancer risk indicators. It was more strongly linked with age, the 20-44 year group being more likely to examine their breasts occasionally and the women 65 years and over being less likely to examine their breasts. Married women were the most likely to practice BSE frequently and widowed or single women most likely never to practice. Women who underwent cervical smear testing were more likely to perform BSE than those who did not have smear tests. Women who learned BSE from their doctors as opposed to other sources practiced BSE more frequently and were more likely to practice BSE exactly as taught.

This survey conducted by FMP trainees in Queensland describes how general practice patients on long term, self administered medications identify their drugs. Trade names are by far the most common means of identification. Generic names and identification by action, colour, and shape and common usage names are less frequently used. Knowledge of alternative trade and generic names is sparse, emphasising the need to inform patients fully of any changes to the brand names of their drugs.

A questionnaire to ascertain their rubella immune status was completed by 212 women, aged 15 to 35 years, attending selected Brisbane general practices. The results were confirmed by rubella serology in 44 per cent of the sample. Only 37 women (18%) reported a history of rubella and 163 (77%) a history of rubella immunisation. Fifty-seven per cent of women with no history of rubella or rubella immunisation were found to be immune. The immune rate for the whole sample was estimated to be 91 per cent. The results emphasise the importance of rubella immune status screening by general practitioners.