Lobar holoprosencephaly: prenatal MR diagnosis with postnatal MR correlation

Holoprosencephaly is a congenital anomaly characterized by lack of cleavage of the prosencephalon. Although, relatively rare, it is the most common anomaly that involves both the brain and the face. Prenatal diagnosis of this anomaly using ultrasonography, particularly of the less severe forms, is difficult. Magnetic resonance imaging has recently become an important complement to US in prenatal diagnosis of CNS anomalies. We herein report a patient in whom, at 23 weeks of gestation, US suggested agenesis of the corpus callosum and in whom, at 24 weeks of gestation, MRI correctly diagnosed lobar holoprosencephaly, which was confirmed by a postnatal MRI at 3 weeks of age. Copyright © 2005 John Wiley & Sons, Ltd.     

Effects of vehicle power on passenger vehicle speeds

Objectives: During the past 2 decades, there have been large increases in mean horsepower and the mean horsepower-to–vehicle weight ratio for all types of new passenger vehicles in the United States. This study examined the relationship between travel speeds and vehicle power, defined as horsepower per 100 pounds of vehicle weight.

Methods: Speed cameras measured travel speeds and photographed license plates and drivers of passenger vehicles traveling on roadways in Northern Virginia during daytime off-peak hours in spring 2013. The driver licensing agencies in the District of Columbia, Maryland, and Virginia provided vehicle information numbers (VINs) by matching license plate numbers with vehicle registration records and provided the age, gender, and ZIP code of the registered owner(s). VINs were decoded to obtain the curb weight and horsepower of vehicles. The study focused on 26,659 observed vehicles for which information on horsepower was available and the observed age and gender of drivers matched vehicle registration records. Log-linear regression estimated the effects of vehicle power on mean travel speeds, and logistic regression estimated the effects of vehicle power on the likelihood of a vehicle traveling over the speed limit and more than 10 mph over the limit.

Results: After controlling for driver characteristics, speed limit, vehicle type, and traffic volume, a 1-unit increase in vehicle power was associated with a 0.7% increase in mean speed, a 2.7% increase in the likelihood of a vehicle exceeding the speed limit by any amount, and an 11.6% increase in the likelihood of a vehicle exceeding the limit by 10 mph. All of these increases were highly significant.

Conclusions: Speeding persists as a major factor in crashes in the United States. There are indications that travel speeds have increased in recent years. The current findings suggest the trend toward substantially more powerful vehicles may be contributing to higher speeds. Given the strong association between travel speed and crash risk and crash severity, this is cause for concern.     

Roadside survey on alcohol and drug use among drivers in the Arctic county of Finnmark (Norway)

Objective: The objective of this study was to determine the prevalence of alcohol and potentially impairing drugs among the general driving population in Finnmark and to compare the prevalence among Norwegian, Russian, and other foreign drivers by analyzing samples of oral fluid.

Methods: In collaboration with local police, drivers were selected for a voluntary and anonymous study using a multistage cluster sampling procedure (selection of roads, time intervals, and drivers within each interval) from September 2014 to October 2015. Age, gender, citizenship, time, and geographical site were recorded. Samples of oral fluid were collected using the Quantisal device. The samples were analyzed for alcohol with an enzymatic method and for 12 illicit drugs and 16 medicinal drugs and some metabolites using ultra-high-performance liquid chromatography with tandem mass spectrometry detection.

Results: A total of 3,228 drivers were asked to participate in the study. The refusal rate was 6.2%. Of the 3,027 participants in the study, 111 (3.7%) were Russian and 204 (6.7%) had citizenship other than Norwegian or Russian. The total prevalence of psychoactive substances was 4.3%. Alcohol was detected in 0.3%, psychoactive medicinal drugs in 2.5%, and illicit drugs in 1.6% of the samples. The most commonly found substances were the sleeping agent zopiclone (1.1%), tetrahydrocannabinol (THC; 1.1%), and the analgesic agent codeine (0.6%). Illicit drugs were detected significantly more often in samples from drivers of citizenship other than Norwegian or Russian. The prevalence of alcohol was somewhat higher among Russian drivers but not statistically significant. There were large differences between age groups and genders concerning illicit drugs and psychoactive medicinal drugs; illicit drugs were more frequently in samples from young male drivers, whereas psychoactive medicinal drugs were more frequently in samples from elderly female drivers.

Conclusion: The total prevalence of alcohol and drugs among the general driving population in Finnmark was low and similar to previous Norwegian roadside surveys. Illicit drugs were detected significantly more often in samples from drivers with citizenship other than Russian and Norwegian and among young male drivers.     

Response of “Alamo” switchgrass tissue chemistry and biomass to nitrogen fertilization in West Tennessee,USA

Switchgrass (Panicum virgatum) is a perennial, warm-season grass that has been identified as a potential biofuel feedstock over a large part of North America. We examined above- and belowground responses to nitrogen fertilization in “Alamo” switchgrass grown in West Tennessee, USA. The fertilizer study included a spring and fall sampling of 5-year old switchgrass grown under annual applications of 0, 67, and 202 kg N ha^?1 (as ammonium nitrate). Fertilization changed switchgrass biomass allocation as indicated by root:shoot ratios. End-of-growing season root:shoot ratios (mean ± SE) declined significantly (P ≤ 0.05) at the highest fertilizer nitrogen treatment (2.16 ± 0.08, 2.02 ± 0.18, and 0.88 ± 0.14, respectively, at 0, 67, and 202 kg N ha^?1). Fertilization also significantly increased above- and belowground nitrogen concentrations and decreased plant C:N ratios. Data are presented for coarse live roots, fine live roots, coarse dead roots, fine dead roots, and rhizomes. At the end of the growing season, there was more carbon and nitrogen stored in belowground biomass than aboveground biomass. Fertilization impacted switchgrass tissue chemistry and biomass allocation in ways that potentially impact soil carbon cycle processes and soil carbon storage.     

Expanding multiple marker screening for Down's syndrome to include Edward'S syndrome

Information on maternal age and maternal serum alpha-fetoprotein, unconjugated oestriol (uE₃), and human chorionic gonadotrophin (hCG) levels was used to investigate retrospectively the effect of estimating Edward's syndrome risk in women having multi-marker screening for Down's syndrome. The screened population comprised 15 pregnancies affected by Edward's syndrome, 15 with Down's syndrome and 5472 unaffected pregnancies. The use of all three markers to estimate Edward's syndrome risk would have led to the detection of 10–12 (67–80 per cent) cases with a false-positive rate of 0.3–0.6 per cent depending on the risk cut-off. A further case would have been detected as a result of screening for Down's syndrome alone. Similar results were obtained when the Edward's syndrome risk was based on uE₃ and hCG only. These data suggest that extending Down's syndrome screening to include Edward's syndrome risk will yield a high detection rate with only a small increase in the false-positive rate.