The way ahead for London's bus priority at traffic signals

London has a long history of successful schemes for bus priority at traffic signals. Recently, transport for London (TfL) has procured a modern automatic vehicle location (AVL) system for bus fleet management, passenger information and bus priority. The new system is known as iBUS and is based on Global Positioning System (GPS) and supporting technologies for bus location. The system eliminates the need for on-street hardware for detecting buses and provides more flexibility and opportunity for using bus detectors. However, bus location based on this system is less accurate than location based on fixed infrastructure (e.g. beacons) and could result in reduced benefits from bus priority. This paper first summarises how bus priority at traffic signals works within iBUS, and then explores the effects of GPS locational errors on bus priority benefits. This is followed by a discussion of opportunities available in the context of iBUS to build an even more efficient and beneficial bus priority system by taking advantage of its cost-effective multiple detection capabilities. The paper is based on various studies carried out by the Transportation Research Group (TRG) at the University of Southampton for TfL.     

Head scatter modelling for irregular field shaping and beam intensity modulation

Scattered radiation from within the treatment head can contribute significant dose to all parts of a radiotherapy treatment field. A multileaf collimator may be used to create an arbitrarily shaped field, and may also be used, under dynamic control, to modulate the beam intensity over the field. This method of intensity modulation is effectively a superposition of a large number of fields which have the same beam direction, but different shapes, and some of these shapes may have unusually small dimensions, particularly in the direction of the leaf movement. Two models for predicting the head scatter under these conditions have been investigated. These are a first-order Compton scatter approximation from the flattening filter, and an empirical fit to measured data using an exponential function. The first model only considers scatter from the flattening filter and has been applied to field sizes between 2 cm by 2 cm and 10 cm by 10 cm, where agreements are all within 1%. However it is not satisfactory at larger field sizes where small scatter contributions, from scattering sources other than the flattening filter, are integrated over large areas. The second model uses measured data between 4 cm by 4 cm and 30 cm by 30 cm to optimize the exponential function and is used to calculate the head scatter contribution for all field sizes. In this case good agreement is achieved over the full field size range, and hence this is a more generally applicable model. Results are presented for static irregularly shaped fields and intensity modulated beams created using a Philips multileaf collimator.     

Using global positioning system for bus priority in London: traffic signals close to bus stops

London's bus network is one of the largest and most comprehensive urban transport systems in the world. The contribution of buses is recognised by implementing a series of initiatives including bus priority at traffic signals. London has a long history of the implementation of bus priority at traffic signals. It has kept pace with the development of new technologies by updating its bus priority system. Now, London is moving towards a bus management system based on global positioning system (GPS), which will also be used to provide bus priority at traffic signals. The authors describe theoretical work carried out by TRG on behalf of Transport for London Bus Priority Team to tackle the challenge posed by locational error associated with GPS where a traffic signal is close to a bus stop     

Carbohydrate chromatography: towards yoctomole sensitivity

Ward atmosphere was assessed with the help of the Ward Atmosphere Scale (WAS) by patients, nurses and physicians on 8 admission units before and after the introduction of the partial open door system. On average, on 45% of the days on which the units could have been potentially open, they were indeed at least temporarily open. Several significant changes in the WAS scores, mostly in desirable direction, were registered. However, close relationship with the partial opening of the units could be substantiated only with regard to the scale "praxis orientation"; still a positive result. No unequivocal relationships could be demonstrated between the introduction of the partial open door system and the changes in the frequency of "special events".     

Glycosylation of prions and its effects on protein conformation relevant to amino acid mutations

The three-dimensional coordinates from a nuclear magnetic resonance (NMR)-averaged structure containing residues 121-226 of mouse prion were used as the starting geometry for MD of prion either with or without glycan in both mutant and wild-type forms. The following mutants were studied: Asp-178 to Asn, Thr-183 to Ala, Phe-198 to Ser, Glu-200 to Lys, and Gln-217 to Arg. NMR data vs structural models were compared to observe any major differences. Simulations of the change in protein structure with and without glycan were performed, as they cannot be tested by NMR analysis. Several mutants were expressed and analyzed for altered glycosylation and the results interpreted in terms of molecular modeling. N-linked glycosylation is likely to play an important role in prion biology as shown by visualization of glycoprotein conformation.     

Green design alternatives for isopropanol recovery in the celecoxib process

Various approaches to solvent recovery have been studied for the manufacturing process of celecoxib, the active ingredient in Celebrex^®. A design case study has been performed by Rowan University with Pfizer through a green engineering partnership program. The manufacturing operation at one of their plants was evaluated and several green engineering alternatives for the purification and recovery of isopropanol (IPA) from waste streams proposed. This separation is complex due to the multiple waste streams generated, with varying compositions of IPA, ethanol, methanol, water, and dissolved solids. Overall goals were waste minimization and IPA recovery and purification. A conceptual study of distillation, extraction, reactive distillation, adsorption, and membrane-based processes was performed. Through use of computer simulation and literature/design methodologies, traditional methods were shown to be unable to obtain high IPA purities with the available equipment. Several green design approaches were evaluated using distillation combined with either molecular sieve adsorption or membrane pervaporation. These process schemes appear to have the most promise to effectively recover and purify IPA. The case study describes equipment and processing issues, and estimates environmental impacts from a life cycle analysis.     

Programmable multiplierless digital filter array for embedded SoCapplications

The authors present a novel, programmable logic array for implementing high performance filter functions within embedded system-on-chip platforms. The novelty of the architecture is demonstrated through its specially tailored configurable logic units, and hierarchical routing scheme. The architecture and routing hierarchy are described using a filter example and results are provided demonstrating scalability, speed, and array utilisation using a typical SoC bus specification     

Characterization of oligosaccharides from an antigenic mannan of Saccharomyces cerevisiae

OBJECTIVE: To examine the relationship between parental adjustment and family adjustment during the period after the children's diagnosis of cancer and the psychological adjustment of children 2 years after their diagnosis. METHOD: The study used a prospective design. Children aged 2 to 5 years with cancer and their parents and families (n = 38) were assessed immediately after the children's diagnosis and again 2 years after the diagnosis. Path analysis was used to investigate the relationship between parental and family adjustment during the period after diagnosis and the psychological adjustment of the children 2 years after their diagnosis. RESULTS: Maternal adjustment during the period after the children's cancer was diagnosed had a significant relationship with the children's psychological adjustment 2 years after diagnosis. In contrast, the adjustment of fathers and family adjustment appeared to have a more limited impact on the later psychological adjustment of the children. CONCLUSION: The level of distress experienced by mothers after the children's diagnosis may have an important influence on the later psychological adjustment of the children. It is possible that this is due to the impact of maternal distress on the capacity of mothers to care for their children during the children's treatment for cancer.     

Monitor chamber backscatter for intensity modulated radiation therapy using multileaf collimators

Children are entitled to their cultural heritage and it is important to their development. Cultural considerations must be incorporated in devising custody and parenting plans. Several generalizations are useful. Children are capable of integrating highly diverse and even contradictory cultural and religious identity fragments. The more distinctly a child's cultural inheritance varies from that of the dominant society, the more it must be taken into account. The more bias or hostility that exists against an aspect of the child's cultural inheritance, the more that cultural component is to be considered. The value of culture to the child is best seen in a developmental context. We are limited in our ability to ensure children's rights to cultural inheritance by our own ethnocentrism or ignorance, by bureaucratic or legalistic definitions of cultural identity, by the desire of one parent to reduce the contribution of the other parent, and by a tendency to rely on consistency as a value in and of itself.