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The first experiment studying the effect of irrigation on pre‐monsoon rainfall in India using a high‐resolution convection‐permitting model has been carried out. This study includes both short (3‐day) experiments and month‐long free‐running simulations, enabling investigation of the effect of irrigation on mesoscale circulations and associated rainfall. In the pre‐monsoon, it is found that irrigation increases rainfall in our simulations. Intriguingly, the rainfall increase found in the high‐resolution model mostly occurs on the mountains near the irrigation rather than over the irrigated region itself. This is because our applied irrigation is in low‐lying regions, and so it enhances the mountain‐valley flows leading to enhancement of diurnally driven orographic rainfall. Because Ganges basin irrigation occurs near mountains which already have some of the highest rainfall rates in the world, and which are subject to flash flooding and landslides, this has significant implications for hazards in mountainous regions during the pre‐monsoon and early monsoon period. [ABSTRACT FROM AUTHOR]

The Plant-Craig stochastic convection parameterization (version 2.0) is implemented in the Met Office Regional Ensemble Prediction System (MOGREPS-R) and is assessed in comparison with the standard convection scheme with a simple stochastic element only, from random parameter variation. A set of 34 ensemble forecasts, each with 24 members, is considered, over the month of July 2009. Deterministic and probabilistic measures of the precipitation forecasts are assessed. The Plant-Craig parameterization is found to improve probabilistic forecast measures, particularly the results for lower precipitation thresholds. The impact on deterministic forecasts at the grid scale is neutral, although the Plant-Craig scheme does deliver improvements when forecasts are made over larger areas. The improvements found are greater in conditions of relatively weak synoptic forcing, for which convective precipitation is likely to be less predictable. [ABSTRACT FROM AUTHOR]

Many numerical models for weather prediction and climate studies are run at resolutions that are too coarse to resolve convection explicitly, but too fine to justify the local equilibrium assumed by conventional convective parametrizations. The Plant-Craig (PC) stochastic convective parametrization scheme, developed in this paper, solves this problem by removing the assumption that a given grid-scale situation must always produce the same sub-grid-scale convective response. Instead, for each time step and grid point, one of the many possible convective responses consistent with the large-scale situation is randomly selected. The scheme requires as input the large-scale state as opposed to the instantaneous grid-scale state, but must nonetheless be able to account for genuine variations in the large-scale situation. Here we investigate the behaviour of the PC scheme in three-dimensional simulations of radiative-convective equilibrium, demonstrating in particular that the necessary space-time averaging required to produce a good representation of the input large-scale state is not in conflict with the requirement to capture large-scale variations. The resulting equilibrium profiles agree well with those obtained from established deterministic schemes, and with corresponding cloud-resolving model simulations. Unlike the conventional schemes, the statistics for mass flux and rainfall variability from the PC scheme also agree well with relevant theory and vary appropriately with spatial scale. The scheme is further shown to adapt automatically to changes in grid length and in forcing strength. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Objectives: To evaluate a South Australian campaign to promote and implement knowledge that taking adequate folate/folic acid in the periconceptional period can reduce the risk of having a baby with a neural tube defect., Design and Setting: The campaign, conducted in October 1994--August 1995, targeted women of reproductive age and health professionals. Evaluation was by computer-assisted telephone interviews undertaken by random dialling throughout the State before and after the campaign, and by self-administered questionnaires to health professionals and women in the postnatal period., Participants: Women of reproductive age and four groups of health professionals., Main Outcome Measures: Knowledge about folate, folate-rich foods and the periconceptional period; participation of health professionals in advising women about folate; use of periconceptional folic acid supplements; sales of folic acid tablets; and prevalence of neural tube defects., Results: Significant increases in knowledge about folate followed the campaign. Health professionals and women in the postnatal period had higher initial levels of knowledge about folate, which also increased significantly. The proportions of women taking periconceptional folic acid supplements, and of health professionals advising women planning a pregnancy about folate, also increased significantly, and folic acid tablet sales doubled. Total prevalence of neural tube defects declined between 1966 and 1999 from a baseline of 2.0 per 1,000 births to 1.1 per 1,000 births (Poisson regression, P= 0.03; average decline of 1.0% per year)., Conclusions: A short educational campaign with a limited budget ($40,000) can promote folate successfully, but alternative strategies such as food fortification are likely to be needed to achieve adequate periconceptional folate intake for a very high proportion of women.

Objectives: To determine the contribution of maternal smoking to preterm birth (< 37 weeks' gestation), small for gestational age (SGA, birthweight < 10th percentile for gestational age) and low birthweight (< 2500 g) among Aboriginal and non-Aboriginal births in South Australia., Design: Retrospective cohort analysis of population-based perinatal data., Setting: The State of South Australia, population 1.5 million., Participants: 36059 women (of whom 851 were Aboriginal women) who had singleton births in 1998-1999., Main Outcome Measures: Relative risks and population-attributable risks of preterm birth, SGA and low birthweight from smoking in the second half of pregnancy, by age and Aboriginality., Results: Aboriginal women had a higher rate of smoking in pregnancy than non-Aboriginal women (57.8% v 24.0% at the first antenatal visit) and high rates for all age groups, while the rates decreased with age among non-Aboriginal women. Heavy smoking increased with age, and Aboriginal women were heavier smokers. Women who smoked had elevated relative risks of preterm birth (1.64), SGA (2.28) and low birthweight (2.52), and all these showed a dose-response relationship. Among Aboriginal (versus non-Aboriginal) births, population-attributable risks were significantly higher for SGA (48% v 21%, and 59% for births to Aboriginal teenagers), low birthweight (35% v 23%) and preterm birth (20% v 11%)., Conclusions: Health promotion programs, with a focus on smoking cessation and reducing uptake of smoking, need to be implemented in an appropriate cultural context, especially among young Aboriginal women. Such a program is being developed in South Australia.

The objective of this study was to determine whether women who have experienced an unexplained stillbirth have a higher risk of adverse perinatal outcomes in subsequent births. We compared 316 subsequent births to women with a previous unexplained stillbirth, with 3160 births to women with no previous history of stillbirth, matched by year of birth, in the period 1987-1997, from the South Australian perinatal database, using logistic regression analysis. There was no increase in the rate of stillbirth and no statistically significant increase in the rate of perinatal death (OR 1.62 [95%CI 0.63-4.20]) or neonatal death, although larger studies are needed to confirm this. However, after adjusting for age, parity, and hospital category of birth, women who had a previous stillbirth had increased incidences in subsequent births of abnormal glucose tolerance or gestational diabetes (a fourfold increase); induction of labour and elective Caesarean section; fetal distress and postpartum haemorrhage; and forceps and emergency Caesarean delivery and preterm birth, which were independent of induction of labour. Gestational age at birth and birthweight were also significantly reduced, suggesting a need for close monitoring of their future pregnancies.

Background: The Medical Research Council Working Party on Congenital Dislocation of the Hip have reported an ascertainment-adjusted incidence of a first operative procedure for congenital dislocation of the hip (CDH) of 0.78 per 1000 livebirths, which is similar to the incidence of CDH before the start of the UK screening programme. The report showed that CDH had not been detected by routine screening before age 3 months in 70% of children reported to the national orthopaedic surveillance scheme. This report raised concerns about the merit of screening at birth for CDH. We aimed to find out the incidence of an operative procedure for CDH in the first 5 years of life among children born in South Australia between 1988 and 1993, and the proportion of these patients that were detected at age 3 months or older., Methods: The state's database for inpatient separations between January, 1988, and April, 1998 was searched. Case records were examined for the age and circumstances of diagnosis, and type of operative procedures. Prevalence rates of CDH were obtained from the South Australian Birth Defects Register, which receives notifications from a statutory perinatal data collection of birth defects detected at birth and subsequent voluntary notifications for children up to age 5 years., Findings: Of the 55 children born in South Australia between 1988 and 1993 identified as having non-teratological CDH and operative procedures, only 22 (40%) had been diagnosed at age 3 months or older. 18 had an open reduction of the hip joint or osteotomy, or both, and the remainder had arthrograms, closed reductions, and/or tenotomy. The prevalence of non-teratological CDH in children was 7.74 per 1000 livebirths. The incidence of surgery for CDH in the first 5 years of life was 0.46 per 1000 livebirths (95% CI 0.34-0.59) and only 0.19 per 1000 livebirths (0.11-0.26) for those diagnosed late (age 3 months or older). These children diagnosed late represented 2.4% of all known cases of CDH., Interpretation: Only 2.4% of known cases of CDH in children born in South Australia had been detected late and required surgery. These results show that a screening programme for CDH can be successful, contrary to the findings of the UK Medical Research Council Working Party.

Year 5 of the Massachusetts Behavioral Health Program was a transition to management by a new private managed care organization. Fifty-eight providers interviewed for an ongoing panel survey reported slightly lower levels of quality, access, utilization, and length of stay than a year earlier. Relationships with providers and advocates improved after an initial difficult period, while consumer and family involvement at all levels remained low. The greatest changes in managed care appeared to take place during the initial transition from fee-for-service care, but intractable problems continue, and full participation of stake-holders seems difficult to achieve.

Pre-eclampsia and placenta accreta have opposite histological features of placentation. This study set out to test the hypotheses that the sex ratios in these two pregnancy complications are opposite and that these conditions are mutually exclusive. A population-based database covering all deliveries in South Australia between 1986 and 1995 and the hospital-based obstetric database of the Adelaide Women's and Children's Hospital, covering 8549 births between 1993 and 1995, were used to ascertain the sex ratios in singleton pregnancies and the sex ratios in those pregnancies in which there was retained placenta, hypertension in pregnancy, or pre-eclampsia. The likelihood of independence of occurrence or mutual exclusivity of retained placenta and hypertension in pregnancy or pre-eclampsia were also examined. The male:female sex ratio in the South Australian population was 1.077. In pregnancies with hypertension in pregnancy it was 1.165 (P<0.001) and in pregnancies with retained placenta it was 0.883 (P<0.0001). There was a trend to an increased sex ratio in pre-eclamptic pregnancy (1.248 in primigravid and 1.092 in multigravid women) but there was insufficient power to detect significance (P=0.207 and 0.470, respectively). Neither hypertension in pregnancy nor pre-eclampsia were mutually exclusive of placenta accreta: hypertensive disorders of pregnancy and placenta accreta occurred independently of each other. Our findings suggest that sex-linked antigens are unlikely to influence maternofetal interactions consistently to give rise to one but not the other pregnancy complication.

Objectives: To describe the impact of rubella immunisation on the incidence of rubella, congenital rubella syndrome and rubella-related terminations of pregnancy in South Australia, and to identify factors associated with a re-emerging problem., Design and Methods: A population-based descriptive study using data from South Australian notifications of disease, births and terminations of pregnancy, the rubella immunisation programme, antenatal rubella antibody screening and paediatric hospital case records., Setting: South Australia (population 1.48 million people; 20,000 births per year)., Main Outcome Measures: Incidence of rubella (age-sex specific), congenital rubella syndrome and rubella-related terminations of pregnancy; antenatal rubella sero-positive rates; rubella immunisation uptake rates., Results: Rubella notification rates in 1990-1996 were significantly higher for males than females for ages 15-34 years. There were five cases of congenital rubella syndrome notified in 1980-1996 compared with at least 20 confirmed or compatible cases in 1965-1979. Rubella-related terminations of pregnancy are now rare, with the last termination for maternal rubella being in 1993. The antenatal rubella sero-positive rate in 1995 was 96.7%, but was significantly lower among Asian women born overseas (78.6% among those 30 years or older). Vaccination uptake rates in schoolgirls decreased between 1990 and 1994 (91.2% to 86.9%)., Conclusions: Since the introduction of rubella immunisation, the incidence of rubella infection among women of reproductive age, and of rubella-related terminations, has fallen. Congenital rubella syndrome has not been notified since 1990 but its risk persists with a recent increase in rubella notifications, a fall in school immunisation rates, a relatively low antenatal sero-positive rate among older Asian women born overseas and the trend towards giving birth at older ages. Effective immunisation programmes must be maintained, particularly in schools and for young children and migrant women.

The oral retinoids isotretinoin and etretinate are uniquely effective in the treatment of severe cystic acne and keratinisation disorders. Because of their known teratogenicity, there are strict prescription guidelines, but exposure during pregnancy still occurs. A dedicated effort by women and their clinicians is required, involving patient selection, education and informed consent, detailed contraceptive counselling, and careful monitoring and management, including pregnancy testing before commencement of therapy.

The oral retinoids, isotretinoin and etretinate, are highly teratogenic drugs which have been available in Australia since 1985 because of their unique effectiveness in severe cystic acne, psoriasis and other keratinization disorders. Only dermatologists can prescribe them, but in spite of strict guidelines by the manufacturers and the College of Dermatologists, exposed pregnancies have occurred. We attempted to determine the circumstances of exposure to these drugs for the 18 pregnancies terminated in South Australia in 1985-1993, using questionnaires to medical practitioners who notified the terminations under legislation. The main reason for their occurrence was the lack of compliance with the use of effective contraception by the women. In South Australia, some prescriptions of oral retinoids by unauthorized doctors have been dispensed during this period. Using statistics on prescriptions dispensed, an estimate was made of 1 termination of pregnancy for 319 courses of treatment for women with isotretinoin. Extension of guidelines for prescription and more detailed counselling in relation to the use of contraception are recommended. It is also suggested that doctors intending to recommend terminations obtain consent to discuss exposure with the dermatologists concerned, who may not be aware of the exposed pregnancy.

Objective: To determine the sensitivity of antenatal screening methods for neural tube defects in population-based screening in South Australia in 1986-1991, and whether ultrasound can replace serum alpha-fetoprotein screening in terms of achieving an equivalent level of sensitivity., Design and Setting: Ascertainment of all births and terminations of pregnancy with neural tube defects from multiple sources for 1986-1991 in South Australia. Serum and amniotic fluid alpha-fetoprotein results were obtained from the only laboratory performing the tests as a Statewide antenatal screening programme, and information on ultrasound screening from case notifications, hospital case records and medical practitioners who cared for the women., Subjects: All 243 births and terminations of pregnancy with neural tube defects in South Australia in 1986-1991., Main Outcome Measures: The sensitivity of individual screening methods and of all methods used, particularly for spina bifida., Results: For pregnancies with neural tube defects screened by any method (serum alpha-fetoprotein, ultrasound or amniocentesis), 86% sensitivity was achieved. Ultrasound screening for anencephaly achieved 100% sensitivity even in low risk pregnancies, compared with 92% for serum alpha-fetoprotein. For spina bifida, the sensitivity of ultrasound screening increased with the level of risk in pregnancy: it was 60% in low risk pregnancies, which was equivalent to that of serum alpha-fetoprotein screening (64%); 89% in high risk pregnancies and 100% for women referred for confirmation of a suspected spina bifida by another ultrasonographer (chi 1(2) for trend = 23.49, P < 0.0001). Ultrasound screening in high risk pregnancies for spina bifida achieved higher sensitivity in teaching hospitals compared with other ultrasound services in the State (97% vs 65%), but sensitivity was equivalent for low risk pregnancies. It is estimated that, had the serum screening programme not been in place, the level of sensitivity achieved for spina bifida by ultrasound and amniocentesis would have been 62% compared with the actual situation of 76% with the programme in existence, a difference of nearly 15% (95% CI 2.5 to 26.7) (chi 1(2) = 5.45, P = 0.02)., Conclusions: Antenatal screening for neural tube defects in South Australia achieved a higher level of sensitivity with the maternal serum alpha-fetoprotein programme in place. We conclude that the serum screening programme should continue in South Australia pending a significant improvement in the sensitivity of routine ultrasound screening for spina bifida.