Monitoring to detect changes in water quality to meet policy objectives.

Detecting change in water quality is key to providing evidence of progress towards meeting water quality objectives. A key measure for detecting change is statistical power. Here we calculate statistical power for all regularly (monthly) monitored streams in New Zealand to test the effectiveness of monitoring for policy that aims to decrease contaminant (phosphorus and nitrogen species, E. coli and visual clarity) concentrations to threshold levels in 5 or 20 years. While > 95% of all monitored sites had sufficient power and samples to detect change in nutrients and clarity over 20 years, on average, sampling frequency would have to double to detect changes in E. coli. Furthermore, to detect changes in 5 years, sampling for clarity, dissolved reactive phosphorus and E. coli would have to increase up to fivefold. The cost of sampling was predicted to increase 5.3 and 4.1 times for 5 and 20 years, respectively. A national model of statistical power was used to demonstrate that a similar number of samples (and cost) would be required for any new monitoring sites. Our work suggests that demonstrating the outcomes of implementing policy for water quality improvement may not occur without a step change in investment into monitoring systems. Emerging sampling technologies have potential to reduce the cost, but existing monitoring networks may also have to be rationalised to provide evidence that water quality is meeting objectives. Our study has important implications for investment decisions involving balancing the need for intensively sampled sites where changes in water quality occur rapidly versus other sites which provide long-term time series.

Global mapping of freshwater nutrient enrichment and periphyton growth potential.

Periphyton (viz. algal) growth in many freshwater systems is associated with severe eutrophication that can impair productive and recreational use of water by billions of people. However, there has been limited analysis of periphyton growth at a global level. To predict where nutrient over-enrichment and undesirable periphyton growth occurs, we combined several databases to model and map global dissolved and total nitrogen (N) and phosphorus (P) concentrations, climatic and catchment characteristics for up to 1406 larger rivers that were analysed between 1990 and 2016. We predict that 31% of the global landmass contained catchments may exhibit undesirable levels of periphyton growth. Almost three-quarters (76%) of undesirable periphyton growth was caused by P-enrichment and mapped to catchments dominated by agricultural land in North and South America and Europe containing 1.7B people. In contrast, undesirable periphyton growth due to N-enrichment was mapped to parts of North Africa and parts of the Middle East and India affecting 280 M people. The findings of this global modelling approach can be used by landowners and policy makers to better target investment and actions at finer spatial scales to remediate poor water quality owing to periphyton growth.

A pilot study of cognitive behavioural therapy and relaxation for migraine headache: a randomised controlled trial.

Headache is being viewed more commonly in a biopsychosocial framework, which introduces the possible utilisation of psychological treatment options, such as cognitive behavioural therapy and relaxation. No such treatments have been trialled in the UK. We conducted a randomised controlled pilot trial, comparing a brief guided self-help CBT and relaxation treatment with standard medical care (SMC), in a UK NHS setting. Participants were recruited from specialist headache clinics across London. Participants were randomised to receive either treatment or standard medical care. Our objective was to provide design information necessary for a future definitive trial of the SHE treatment, including, recruitment/retention rates, acceptability of randomisation, treatment fidelity and estimations of mean and variances of outcome measures. From the initial 275 patients identified, 73 were randomised. There was no difference in drop-out rates between SMC and treatment groups. Of the 36 participants randomised to receive treatment, 72% attended all sessions. Findings show that a future definitive trial of the SHE treatment is feasible, with small modifications of protocol, within a UK NHS context.

Preterm delivery risk in relation to maternal HIV infection, history of malaria and other infections among urban Zimbabwean women.

OBJECTIVE: To examine preterm delivery risk in relation to maternal HIV infection, malaria history, and other infections among Zimbabwean women. DESIGN: Hospital based, cross sectional study. SETTING: Harare Maternity Hospital, Harare, Zimbabwe. SUBJECTS: A convenient sample of 500 pregnant women. MAIN OUTCOME MEASURE: Preterm delivery. THE STUDY FACTORS: Maternal socio-demographic information, and infectious disease history (during the year before pregnancy). METHOD: Between July 1998 and March 1999 data were collected for a cross sectional study of pregnant women who delivered at the Harare Maternal Hospital. The association of maternal HIV infection, history of malaria, and other infections with preterm delivery were determined using multivariate analysis. RESULTS: Overall, 497 women were studied, 444 (89.3%) delivered at term and 53 women (10.7%) delivered preterm. Women who delivered preterm were less likely to be HIV seropositive compared with others (odds ratio [OR] = 0.75. 95% confidence interval (CI): 0.38 to 21.48). Preterm delivery was associated with having tuberculosis infections in the year prior to the pregnancy (OR = 10.15, 95% CI: 1.15 to 89.87). Other infections associated with preterm delivery were malaria (OR = 2.39, 95% CI: 1.07 to 5.31), chest infections (OR = 2.63, 95% CI: 0.76 to 9.17), and Herpes (shingles) infection (OR = 2.58, 95% CI: 0.56 to 11.85). Overall, a positive history of any of the non-sexually transmitted infections (in aggregate) was associated with a 3.20 fold increase risk for preterm delivery (OR = 3.20. 95% CI: 1.59 to 6.43). Women with a history of infection and who did not use iron supplements during pregnancy, compared with women without such an history and who used iron supplements, experienced the highest risk for preterm delivery (OR = 8.34, 95% CI: 3.30 to 21.07). CONCLUSION: Maternal non-STD infections, (i.e., tuberculosis, malaria, and chest infections) occurring in the year prior to pregnancy were associated with an increased risk of preterm delivery. The association of non-sexually transmitted infections and preterm delivery was particularly strong among women who did not use iron supplements during pregnancy.

The metabolism of nitrilotriacetate by a pseudomonad.

1. An organism that grows on nitrilotriacetate as sole source of carbon and energy was isolated in pure culture and was identified as a pseudomonad. 2. Cell-free extracts of the nitrilotriacetate-grown pseudomonad contain an enzyme that catalyses the NADH-and O(2)-dependent oxidation of nitrilotriacetate to iminodiacetate and glyoxalate. This enzyme is absent from extracts of glucose-grown cells. 3. Compared with growth on glucose, growth on nitrilotriacetate results in increased activities of enzymes of glycine and serine metabolism, namely serine hydroxymethyltransferase, glycine decarboxylase, serine-oxaloacetate aminotransferase and hydroxypyruvate reductase. 4. Cell-free extracts of the nitrilotriacetate-grown organism contain the enzyme glyoxalate carboligase and, when supplemented with NADH, Mg(2+) and thiamin pyrophosphate, can catalyse the anaerobic conversion of glyoxalate into glycerate. 5. These results are incorporated in a scheme which shows the oxidative metabolism of nitrilotriacetate by the successive removal of C(2) units to form 2mol of glyoxalate and 1mol of glycine per mol of nitrilotriacetate degraded. The glyoxalate and glycine are then both metabolized to glycerate by separate pathways, via tartronic semialdehyde and serine respectively. The role of this scheme in the growth of the organism on nitrilotriacetate is discussed.