No abstract

No abstract

We evaluated 13 children with cerebral palsy who had birthweights under 1085 g. A magnetic resonance image (MRI) of the head was obtained, the findings were compared, and the neonatal records were reviewed. The individual children were classified as to the type of cerebral palsy. On MRI, all had severe injury to the inferior cerebellar hemispheres, mostly symmetric, and in some there was injury to the inferior vermis. The average birthweight was 668 g, and the gestational ages were 24 to 27 weeks. No other outstanding prenatal or postnatal problems were identified. The children had different types of severe cerebral palsy, with only 3 being able to walk. Almost all were mentally retarded and microcephalic. All had visual problems. This report defines a previously underappreciated injury to the cerebellum in extremely premature infants. Further clinical, laboratory, and pathologic studies are needed to better define the underlying mechanisms.

No abstract

Traffic incidents generate adverse impacts in many areas, including traffic flow, air pollution, fuel consumption, and secondary crashes; therefore, it is vital for traffic incident responders and operators to know how they can improve the efficiency of traffic incident management. This paper presents the results of an investigation of the effects of traffic accident characteristics on accident clearance time using fully parametric hazard-based duration models with emphasis on the accelerated failure time metric. Accident characteristics and clearance times were obtained from Abu Dhabi, the capital of the United Arab Emirates. The data were obtained from the Federal Traffic Statistics System and the records of the Abu Dhabi Collision Investigation Branch for the period from May 2009 to April 2010. For the purpose of this study, clearance time was defined as the length of time from the arrival of the collision investigator on the accident scene to the departure of the collision investigator from the scene. According to the goodness-of-fit test conducted in the study, the Weibull model without gamma heterogeneity was used. The estimation results show that various accident characteristics significantly affect clearance time; these characteristics include month, location, weather condition, accident type, number of causalities, and number of vehicles involved. These results highlight some weak points in the current practices of clearing accidents in Abu Dhabi. Accordingly, this paper suggests some mitigation measures.

Hydraulic fracturing (fracking) has been used extensively in the US and Canada since the 1950s and offers the potential for significant new sources of oil and gas supply. Numerous other countries around the world (including the UK, Germany, China, South Africa, Australia and Argentina) are now giving serious consideration to sanctioning the technique to provide additional security over the future supply of domestic energy. However, relatively high population densities in many countries and the potential negative environmental impacts that may be associated with fracking operations has stimulated controversy and significant public debate regarding if and where fracking should be permitted. Road traffic generated by fracking operations is one possible source of environmental impact whose significance has, until now, been largely neglected in the available literature. This paper therefore presents a scoping-level environmental assessment for individual and groups of fracking sites using a newly-created Traffic Impacts Model (TIM). The model produces estimates of the traffic-related impacts of fracking on greenhouse gas emissions, local air quality emissions, noise and road pavement wear, using a range of hypothetical fracking scenarios to quantify changes in impacts against baseline levels. Results suggest that the local impacts of a single well pad may be short duration but large magnitude. That is, whilst single digit percentile increases in emissions of CO2, NOx and PM are estimated for the period from start of construction to pad completion (potentially several months or years), excess emissions of NOx on individual days of peak activity can reach 30% over baseline. Likewise, excess noise emissions appear negligible (<1dBA) when normalised over the completion period, but may be considerable (+3.4dBA) in particular hours, especially in night-time periods. Larger, regional scale modelling of pad development scenarios over a multi-decade time horizon give modest CO2 emissions that vary between 2.5 and 160.4kT, dependent on the number of wells, and individual well fracking water and flowback waste requirements. The TIM model is designed to be adaptable to any geographic area where the required input data are available (such as fleet characteristics, road type and quality), and we suggest could be deployed as a tool to help reach more informed decisions regarding where and how fracking might take place taking into account the likely scale of traffic-related environmental impacts.

No abstract

No abstract