Modelling drivers' car parking behaviour using data from a travel choice simulator

This paper reports on models developed from data collected using the PARKIT parking choice simulator. PARKIT provided an experimental environment in which drivers’ choice of car parks, and of the routes chosen to reach them, could be observed and the influence of different levels of parking-stock knowledge (derived from experience or from information provided via roadside message signs) monitored. Separate models were estimated for the drivers’ initial choice of car park and for their revision of that choice as their journey progresses and they learn about actual conditions. The importance of price, walking time and driving distance is confirmed but the addition of variables describing the drivers’ choices on previous days, their expectations and their immediately preceding route-choice, greatly improved the models’ explanatory power. It is noted that variables such as these are not generally considered because they are rarely available to the modeller. Different discrete choice model structures were found to be appropriate for different decisions. Route choice was represented as an exit-choice model (whereby each journey is treated as a sequence of decisions – one at each intersection encountered). The paper discusses the incorporation of these choice models into a network assignment model and concludes that much of the power of the choice models is lost if the network model is not able to support use of information about travellers’ socio-economic characteristics and knowledge of the network and about the detailed network topology

Road user charging and social exclusion: The impact of congestion charges on at-risk groups.

The importance of social exclusion in the context of congestion charging is discussed, and the groups most particularly at-risk identified. A new technique, based on generation and investigation of a synthetic population is introduced and used to establish the impacts on at-risk groups of six congestion charging schemes in Leeds. The distribution and severity of impacts are seen to depend crucially on the precise definition of the charge area, the basis of the charges and exemptions provided. Using the new technique, it can be seen how the impact on at-risk groups could be minimized without compromising the overall objectives of congestion charging. Further potential applications of the new technique are outlined

Co-introduction of charges on urban roads and motorways in metropolitan areas: a model-based investigation

This paper explores the relationship between charges on motorways and on other types of road. It draws on a model-based study of different pricing scenarios which was conducted within an EU-funded investigation of differentiated infrastructure charges (the DIFFERENT project). The scenarios covered strategies ranging from full charging on all roads irrespective of category, on motorways only, on motorway access roads, on urban roads only, and at cordons. A number of different charge levels were tested. The test results suggested that positive impacts and revenues are maximised by applying charges to each link which reflect the contribution to externalities made by the marginal user of that link - irrespective of whether it is a motorway link or an urban link. However, when implementation costs are taken into account, the best performing scheme was a cordon charge combined with a per-km charge for use of motorways outside the cordon. Fixed per-km charges on motorways or on urban roads are much less effective than charges which are differentiated to reflect congestion on individual links. The introduction of charges only on motorways produces little benefit and causes unwanted diversion to urban roads, and although the introduction of a charge designed to protect the level of service enjoyed by strategic motorway traffic succeeds in achieving that goal, it yields little revenue and has little overall impact on delay or other externalities. The paper highlights the practical implications of these results and notes that, although it is likely to be easier to gain political support for introducing charges on motorways than on other types of road, the benefits from so doing are generally lower than can be obtained by introducing charges on congested urban roads

Understanding the role of performance targets in transport policy

The measurement of performance in the public sector has become increasingly important in recent years and it is now commonplace for transport organisations, and local and national governments, to publish performance goals for service supply and quality. Such commitments, when time referenced, are known as targets. This paper explain how changes in management style, consumer rights legislation, contractual obligations and other factors have combined to make management-by targets increasingly common in the public sector. The advantages and disadvantages of management-by-targets are illustrated through discussion of the processes and experience of setting transport targets in UK national transport policy. We conclude that while some of the targets have had a significant impact on policy makers, managers and their agents, the effects have not always been as intended

Reducing intrusive traumatic memories after emergency caesarean section: A proof-of-principle randomized controlled study.

UNLABELLED: Preventative psychological interventions to aid women after traumatic childbirth are needed. This proof-of-principle randomized controlled study evaluated whether the number of intrusive traumatic memories mothers experience after emergency caesarean section (ECS) could be reduced by a brief cognitive intervention. 56 women after ECS were randomized to one of two parallel groups in a 1:1 ratio: intervention (usual care plus cognitive task procedure) or control (usual care). The intervention group engaged in a visuospatial task (computer-game 'Tetris' via a handheld gaming device) for 15 min within six hours following their ECS. The primary outcome was the number of intrusive traumatic memories related to the ECS recorded in a diary for the week post-ECS. As predicted, compared with controls, the intervention group reported fewer intrusive traumatic memories (M = 4.77, SD = 10.71 vs. M = 9.22, SD = 10.69, d = 0.647 [95% CI: 0.106, 1.182]) over 1 week (intention-to-treat analyses, primary outcome). There was a trend towards reduced acute stress re-experiencing symptoms (d = 0.503 [95% CI: -0.032, 1.033]) after 1 week (intention-to-treat analyses). Times series analysis on daily intrusions data confirmed the predicted difference between groups. 72% of women rated the intervention "rather" to "extremely" acceptable. This represents a first step in the development of an early (and potentially universal) intervention to prevent postnatal posttraumatic stress symptoms that may benefit both mother and child. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT02502513

Cyclotron resonance lineshape in a Wigner crystal

The cyclotron resonance absorption spectrum in a Wigner crystal is calculated. Effects of spin-splitting are modelled by substitutional disorder, and calculated in the coherent potential approximation. Due to the increasing strength of the dipole-dipole interaction, the results show a crossover from a double-peak spectrum at small filling factors to a single-peak spectrum at filling factors \agt 1/6. Radiation damping and magnetophonon scattering can also influence the cyclotron resonance. The results are in very good agreement with experiments.Comment: 4 pages REVTEX, attempt to append 3 figures that seem to have been lost last tim

Phylogenetic analysis consistent with a clinical history of sexual transmission of HIV-1 from a single donor reveals transmission of highly distinct variants

BACKGROUND To combat the pandemic of human immunodeficiency virus 1 (HIV-1), a successful vaccine will need to cope with the variability of transmissible viruses. Human hosts infected with HIV-1 potentially harbour many viral variants but very little is known about viruses that are likely to be transmitted, or even if there are viral characteristics that predict enhanced transmission in vivo. We show for the first time that genetic divergence consistent with a single transmission event in vivo can represent several years of pre-transmission evolution. RESULTS We describe a highly unusual case consistent with a single donor transmitting highly related but distinct HIV-1 variants to two individuals on the same evening. We confirm that the clustering of viral genetic sequences, present within each recipient, is consistent with the history of a single donor across the viral env, gag and pol genes by maximum likelihood and bayesian Markov Chain Monte Carlo based phylogenetic analyses. Based on an uncorrelated, lognormal relaxed clock of env gene evolution calibrated with other datasets, the time since the most recent common ancestor is estimated as 2.86 years prior to transmission (95% confidence interval 1.28 to 4.54 years). CONCLUSION Our results show that an effective design for a preventative vaccine will need to anticipate extensive HIV-1 diversity within an individual donor as well as diversity at the population level

Genome-to-genome analysis highlights the effect of the human innate and adaptive immune systems on the hepatitis C virus

Outcomes of hepatitis C virus (HCV) infection and treatment depend on viral and host genetic factors. Here we use human genome-wide genotyping arrays and new whole-genome HCV viral sequencing technologies to perform a systematic genome-to-genome study of 542 individuals who were chronically infected with HCV, predominantly genotype 3. We show that both alleles of genes encoding human leukocyte antigen molecules and genes encoding components of the interferon lambda innate immune system drive viral polymorphism. Additionally, we show that IFNL4 genotypes determine HCV viral load through a mechanism dependent on a specific amino acid residue in the HCV NS5A protein. These findings highlight the interplay between the innate immune system and the viral genome in HCV control