Non-universal scaling and dynamical feedback in generalized models of financial markets

We study self-organized models for information transmission and herd behavior in financial markets. Existing models are generalized to take into account the effect of size-dependent fragmentation and coagulation probabilities of groups of agents and to include a demand process. Non-universal scaling with a tunable exponent for the group size distribution is found in the resulting system. We also show that the fragmentation and coagulation probabilities of groups of agents have a strong influence on the average investment rate of the system

A 2018 Customer Satisfaction Survey with Users of a Subsidised Private Bus Service in Cape Town, South Africa

Golden Arrow Bus Services (Pty) Ltd. (GABS) is the largest private bus company in the Western Cape province of South Africa. It operates subsidised, scheduled transport services to commuters in Cape Town Metropolitan Municipality under a contract with the Western Cape Department of Transport. To independently assess service quality, the company has commissioned the Cape Peninsula University of Technology to undertake biennial customer satisfaction surveys. The survey’s 2018 iteration was conducted during the week of 10 to 14 September 2018 with a sample of n=2677 quasi-randomly selected customers interviewed during morning and afternoon peak hours at six bus termini. The main section of the questionnaire measured satisfaction using a perceived service quality (PSQ) scale consisting of 20 individual service quality items. Overall satisfaction was measured by aggregating individual item scores into a PSQ index and was also separately measured directly using a ten-point scale. A gap scoring technique was used to measure the relative importance of the service quality items, enabling an importance-performance analysis (IPA) to be conducted (cf. Martilla, 1977). Data was also collected on demographic characteristics and service usage. Self-reported customer satisfaction was reasonably high (a mean of 7.2 on a scale from 1 to 10). Items for which mean customer satisfaction was the highest were “Ease of getting on and off the bus,” “Driving ability of drivers,” and “Reliability of buses not to break down.” Items for which mean customer satisfaction was lowest were “Condition of bus stops and shelters,” “Level of safety from crime,” and “Level of crowding on buses.” The PSQ scale was found to be internally consistent in terms of Cronbach’s Alpha, and the PSQ index was found to correlate strongly with service usage indicators. The PSQ scale is suitable as a tool for measuring customer satisfaction with bus services in a South African context.Papers presented at the 38th International Southern African Transport Conference on "Disruptive transport technologies - is South and Southern Africa ready?" held at CSIR International Convention Centre, Pretoria, South Africa on 8th to 11th July 2019

Studies of the limit order book around large price changes

We study the dynamics of the limit order book of liquid stocks after experiencing large intra-day price changes. In the data we find large variations in several microscopical measures, e.g., the volatility the bid-ask spread, the bid-ask imbalance, the number of queuing limit orders, the activity (number and volume) of limit orders placed and canceled, etc. The relaxation of the quantities is generally very slow that can be described by a power law of exponent $\approx0.4$. We introduce a numerical model in order to understand the empirical results better. We find that with a zero intelligence deposition model of the order flow the empirical results can be reproduced qualitatively. This suggests that the slow relaxations might not be results of agents' strategic behaviour. Studying the difference between the exponents found empirically and numerically helps us to better identify the role of strategic behaviour in the phenomena.Comment: 19 pages, 7 figure

Considerations in relation to off-site emergency procedures and response for nuclear accidents

The operation of nuclear facilities has, fortunately, not led to many accidents with off-site consequences. However, it is well-recognised that should a large release of radioactivity occur, the effects in the surrounding area and population will be significant. These effects can be mitigated by developing emergency preparedness and response plans prior to the operation of the nuclear facility that can be exercised regularly and implemented if an accident occurs. This review paper details the various stages of a nuclear accident and the corresponding aspects of an emergency preparedness plan that are relevant to these stages, both from a UK and international perspective. The paper also details how certain aspects of emergency preparedness have been affected by the accident at Fukushima Dai-ichi and as a point of comparison how emergency management plans were implemented following the accidents at Three Mile Island 2 and Chernobyl. In addition, the UK’s economic costing model for nuclear accidents COCO-2, and the UK’s Level-3 Probabilistic Safety Assessment code “PACE” are introduced. Finally, the factors that affect the economic impact of a nuclear accident, especially from a UK standpoint, are described

School-based interventions TO Prevent Dating and Relationship Violence and Gender-Based Violence: STOP-DRV-GBV systematic review

Background Schools have a duty of care to prevent violence between students but a significant amount of dating and relationship violence and gender-based violence occurs in schools. These are important public health issues with important longitudinal consequences for young people. Objectives To understand functioning and effectiveness of school-based interventions for the prevention of dating and relationship violence and gender-based violence. Review methods We undertook a mixed-methods systematic review to synthesise different types of evidence relating to school-based interventions for the prevention of dating and relationship violence and gender-based violence to understand if, how and in what ways these interventions are effective. We searched 21 databases and 2 trial registers and undertook forwards and backwards citation chasing, author contact and other supplementary search methods. Searches identified all literature published to June 2021. All screening was undertaken in duplicate and independently, and we quality appraised all included studies. Results We included 247 reports (68 outcome evaluations, 137 process evaluations). Synthesis of intervention components produced an intervention typology: single-component, curricular, multicomponent, and multilevel programmes. Synthesis of intervention theories suggested that interventions aiming to increase students’ sense of school belonging and sense of safety in the school building could encourage increased learning of prosocial skills and increased prosocial peer norms, and so potentially reducing dating and relationship violence and gender-based violence. Synthesis of factors affecting delivery highlighted school organisation and leaders who believed in the importance of addressing dating and relationship violence/gender-based violence, along with time and resources to deliver the interventions. The ease with which the intervention could be delivered and modified was also important. Meta-analysis found stronger evidence for intervention effectiveness in reducing dating and relationship violence than for gender-based violence, with significant long-term impacts on dating and relationship violence victimisation and perpetration, and some evidence that interventions in high-income countries could be effective for reducing victimisation and perpetration of gender-based violence in the long-term. Impacts on knowledge and attitudes were primarily short-term. Network meta-analysis did not suggest superiority of any intervention type. Moderation evidence suggested interventions reduced dating and relationship violence perpetration in boys more than girls, but reduced gender-based violence perpetration more in girls. Metaregression by intervention component did not explain heterogeneity in effectiveness, but qualitative comparative analysis suggested that reducing perpetration was important to reducing victimisation, and that perpetration could be reduced via focus on interpersonal skills, guided practice and (for gender-based violence) implementation of social structural components. Limitations Despite an exhaustive search, trials may have been missed and risk of publication bias was high for several analyses. Conclusions This is the most comprehensive systematic review of school-based interventions for dating and relationship violence and gender-based violence to date. It is clear that the prevention of dating and relationship violence and gender-based violence in schools will require longer-term investment to show benefit

CSF1R inhibitor JNJ-40346527 attenuates microglial proliferation and neurodegeneration in P301S mice

Neuroinflammation and microglial activation are significant processes in Alzheimer's disease pathology. Recent genome-wide association studies have highlighted multiple immune-related genes in association with Alzheimer's disease, and experimental data have demonstrated microglial proliferation as a significant component of the neuropathology. In this study, we tested the efficacy of the selective CSF1R inhibitor JNJ-40346527 (JNJ-527) in the P301S mouse tauopathy model. We first demonstrated the anti-proliferative effects of JNJ-527 on microglia in the ME7 prion model, and its impact on the inflammatory profile, and provided potential CNS biomarkers for clinical investigation with the compound, including pharmacokinetic/pharmacodynamics and efficacy assessment by TSPO autoradiography and CSF proteomics. Then, we showed for the first time that blockade of microglial proliferation and modification of microglial phenotype leads to an attenuation of tau-induced neurodegeneration and results in functional improvement in P301S mice. Overall, this work strongly supports the potential for inhibition of CSF1R as a target for the treatment of Alzheimer's disease and other tau-mediated neurodegenerative diseases

Inflammatory biomarkers in Alzheimer's disease plasma

Introduction: Plasma biomarkers for Alzheimer's disease (AD) diagnosis/stratification are a \u201cHoly Grail\u201d of AD research and intensively sought; however, there are no well-established plasma markers. Methods: A hypothesis-led plasma biomarker search was conducted in the context of international multicenter studies. The discovery phase measured 53 inflammatory proteins in elderly control (CTL; 259), mild cognitive impairment (MCI; 199), and AD (262) subjects from AddNeuroMed. Results: Ten analytes showed significant intergroup differences. Logistic regression identified five (FB, FH, sCR1, MCP-1, eotaxin-1) that, age/APO\u3b54 adjusted, optimally differentiated AD and CTL (AUC: 0.79), and three (sCR1, MCP-1, eotaxin-1) that optimally differentiated AD and MCI (AUC: 0.74). These models replicated in an independent cohort (EMIF; AUC 0.81 and 0.67). Two analytes (FB, FH) plus age predicted MCI progression to AD (AUC: 0.71). Discussion: Plasma markers of inflammation and complement dysregulation support diagnosis and outcome prediction in AD and MCI. Further replication is needed before clinical translation