Single Atom Detection from Low Contrast-to-Noise Ratio Electron Microscopy Images.

Single atom detection is of key importance to solving a wide range of scientific and technological problems. The strong interaction of electrons with matter makes transmission electron microscopy one of the most promising techniques. In particular, aberration correction using scanning transmission electron microscopy has made a significant step forward toward detecting single atoms. However, to overcome radiation damage, related to the use of high-energy electrons, the incoming electron dose should be kept low enough. This results in images exhibiting a low signal-to-noise ratio and extremely weak contrast, especially for light-element nanomaterials. To overcome this problem, a combination of physics-based model fitting and the use of a model-order selection method is proposed, enabling one to detect single atoms with high reliability.

Pregnancy outcomes of mothers with an alcohol-related diagnosis: a population-based cohort study for the period 1983-2007.

OBJECTIVE: To examine fetal outcomes of mothers with an alcohol-related diagnosis. DESIGN: Population-based cohort. SETTING: Western Australia (WA). POPULATION: Births on the WA Midwives Notification System (1983-2007). METHODS: Infants of mothers with an alcohol-related diagnosis [International Classification of Disease (ICD), 9th/10th revisions] recorded on WA health data sets (non-Aboriginal n = 13 807; Aboriginal n = 9766) were identified through the WA data linkage system. A comparison cohort of infants born to mothers without an alcohol diagnosis was frequency matched on maternal age, year of birth of the offspring, and Aboriginal status (non-Aboriginal n = 40 148; Aboriginal n = 20 643). MAIN OUTCOME MEASURES: Poisson regression-generated adjusted relative risk (aRR) and 95% confidence intervals (95% CIs) for small for gestational age (SGA), preterm birth, and low-Apgar score, calculated separately for non-Aboriginal and Aboriginal infants of mothers with an alcohol diagnosis recorded during pregnancy and any alcohol diagnosis. Population-attributable fractions were calculated. RESULTS: The aRR for non-Aboriginal infants when a maternal alcohol diagnosis was recorded during pregnancy ranged from 1.79 (95% CI 1.42-2.16) for SGA to 2.57 (95% CI 1.69-4.27) for preterm birth <32 weeks of gestation, and for Aboriginal infants ranged from 2.69 (95% CI 2.28-3.16) to 1.99 (95% CI 1.40-2.84), respectively. The highest population-attributable fractions were for any alcohol diagnosis and for Aboriginal infants. For Aboriginal births, approximately 9% (95% CI 4.74-12.97) and 10.1% (95% CI 5.50-14.49) of moderate and very preterm births, respectively, and 24.4% (95% CI 13.5-21.2%) of SGAs were attributable to having a mother with any alcohol-related diagnosis. CONCLUSIONS: Mothers with an alcohol diagnosis are at increased risk of poor pregnancy outcomes. The public health impact of maternal alcohol-use disorders on fetal outcomes is significant.

Alcohol-use disorders during and within one year of pregnancy: a population-based cohort study 1985-2006.

OBJECTIVES: To examine alcohol-use disorders in pregnant women and the extent of under-reporting. DESIGN: Population-based cohort study. SETTING: Western Australia. POPULATION: Women with a birth recorded on the Western Australian Midwives Notification System (1985-2006). METHODS: Mothers with an International Classification of Diseases 9/10 alcohol-related diagnosis, indicating heavy alcohol consumption, recorded on population-based health datasets (non-Aboriginal n=5,839; Aboriginal n=2,583) were identified through the Western Australian data-linkage system. This 'exposed' cohort was frequency matched (on maternal age, year of birth of offspring, Aboriginal status) with comparison mothers without an alcohol-related diagnosis (non-Aboriginal n=33,979; Aboriginal n=8,005). MAIN OUTCOME MEASURES: Trends in maternal alcohol diagnoses in relation to pregnancy for non-Aboriginal and Aboriginal women. The proportion of children diagnosed with fetal alcohol syndrome (FAS) who had a mother with an alcohol diagnosis recorded during pregnancy. RESULTS: The proportion of Aboriginal mothers in Western Australia with an alcohol diagnosis (23.1%) is ten times greater than for non-Aboriginal mothers (2.3%). There has been a six-fold increase in the percentage of non-Aboriginal births with a maternal alcohol diagnosis recorded during pregnancy and a 100-fold increase for Aboriginal births. Around 70% of the mothers of children diagnosed with FAS did not have an alcohol diagnosis recorded during pregnancy and 18% of the mothers had no record of an alcohol diagnosis. CONCLUSIONS: Maternal alcohol exposure during pregnancy is significantly under-ascertained. Given the severe risks to the fetus from heavy prenatal alcohol exposure, assessment and recording of alcohol use should be routinely undertaken in maternity and other health settings.

A new method of prenatal alcohol classification accounting for dose, pattern and timing of exposure: improving our ability to examine fetal effects from low to moderate alcohol.

BACKGROUND: When examining the association between prenatal alcohol exposure and fetal effects, the timing and intensity of exposure have been ignored in epidemiological studies. The effect of using dose, pattern and timing of consumption ("composite" method) was investigated in this study, to examine the association between prenatal alcohol exposure and fetal effects. METHODS: The composite method resulted in six categories of exposure (abstinent, low, moderate, binge

The effect of maternal alcohol consumption on fetal growth and preterm birth.

OBJECTIVE: To investigate the relationship between prenatal alcohol exposure and fetal growth and preterm birth and to estimate the effect of dose and timing of alcohol exposure in pregnancy. DESIGN: A population-based cohort study linked to birth information on the Western Australian Midwives Notification System. SETTING: Western Australia. POPULATION: A 10% random sample of births restricted to nonindigenous women who had delivered a singleton infant (n= 4719) in 1995-1997. METHODS: The impact of alcohol consumption in pregnancy on fetal growth (small-for-gestational-age [SGA] and large-for-gestational-age infants [LGA]) and preterm birth (<37 weeks of gestation) was assessed using multivariate logistic regression analysis and adjusting for confounding factors. MAIN OUTCOME MEASURES: Odds ratios and 95% CI, attributable risk, and population attributable risk were calculated. RESULTS: The percentage of SGA infants and preterm birth increased with higher levels of prenatal alcohol exposure; however, the association between alcohol intake and SGA infants was attenuated after adjustment for maternal smoking. Low levels of prenatal alcohol were not associated with preterm birth; however, binge drinking resulted in a nonsignificant increase in odds. Preterm birth was associated with moderate and higher levels of prenatal alcohol consumption for the group of women who ceased drinking before the second trimester. This group of women was significantly more likely to deliver a preterm infant than women who abstained from alcohol (adjusted OR 1.73 [95% CI 1.01-3.14]). CONCLUSIONS: Alcohol intake at higher levels, particularly heavy and binge drinking patterns, is associated with increased risk of preterm birth even when drinking is ceased before the second trimester. This finding, however, is based on small numbers and needs further investigation. Dose and timing of prenatal alcohol exposure appears to affect preterm delivery and should be considered in future research and health education.

Trends in mode of delivery during 1984-2003: can they be explained by pregnancy and delivery complications?

OBJECTIVES: To describe trends in mode of delivery, to identify significant factors which affected mode of delivery, and to describe how these factors and their impact have changed over time. DESIGN: Total population birth cohort. SETTING: Western Australia 1984-2003. PARTICIPANTS: The analysis was restricted to all singleton infants delivered at 37-42 weeks of gestation with a cephalic presentation (n = 432,327). METHODS: Logistic regression analyses were undertaken to estimate significant independent risk factors separately for elective and emergency caesarean sections compared with vaginal delivery (spontaneous and instrumental), adjusting for potential confounding variables. MAIN OUTCOME MEASURES: Trends in mode of delivery, demographic factors, and pregnancy and delivery complications. Estimated likelihood of elective caesarean section compared with vaginal delivery and emergency caesarean section compared with vaginal delivery. RESULTS: Between 1984-88 and 1999-2003, the likelihood of women having an elective caesarean section increased by a factor of 2.35 times (95% CI 2.28-2.42) and the likelihood of an emergency caesarean section increased 1.89 times (95% CI 1.83-1.96). These caesarean section rate increases remained even after adjustment for their strong associations with many sociodemographic factors, obstetric risk factors, and obstetric complications. Rates of caesarean section were higher in older mothers, especially those older than 40 years of age (elective caesarean section, OR 5.42 [95% CI 4.88-6.01]; emergency caesarean section, OR 2.67 [95% CI 2.39-2.97]), and in nulliparous women (elective caesarean section, OR 1.54 [95% CI 1.47-1.61]; emergency caesarean section, OR 3.61 [95% CI 3.47-3.76]). CONCLUSIONS: Our data show significant changes in mode of delivery in Western Australia from 1984-2003, with an increasing trend in both elective and emergency caesarean section rates that do not appear to be explained by increased risk or indication.

Fetal alcohol syndrome: diagnosis, epidemiology, and developmental outcomes.

In Australia the issue of fetal alcohol syndrome (FAS) has not been the subject of policy development or of extensive research. There is a lack of knowledge, both in the general community and by health professionals, of the nature of the risks associated with heavy alcohol consumption during pregnancy and the factors that increase this risk. This paper reviews the literature surrounding FAS with the aim of providing the reader an understanding of the diagnostic features and epidemiology of FAS and of the developmental sequelae associated with this syndrome.