A highly accurate, inexpensive procedure for computing theoretical chronoamperometric current at cylindrical wire electrodes

Cylindrical wire or fiber electrodes are attractive for electro-analytical applications, but the theory of transient methods at such electrodes is complicated, implying that theoretical discussions and experimental data analysis usually rely on various approximations. In particular, a number of approximate expressions has been proposed in the literature to describe the chronoamperometric limiting current at such electrodes. All these expressions have a low accuracy. In the present work a new, highly accurate and computationally inexpensive procedure for computing the current is presented. The procedure relies on local polynomial approximations covering the entire time domain, and provides at least 14–15 significant digits. It can therefore be useful both for theoretical purposes (e.g. as a source of reference values for testing electrochemical digital simulation techniques that are usually less accurate), and for the analysis of the experimental data.     

Hostile intent in public crowded spaces: A field study

Hostile reconnaissance is vital to successful terrorist activity. Individuals carrying out this activity are likely to experience raised levels of stress and this will manifest itself at biological, physiological, psychological and behavioural levels, providing an opportunity for detection. A field trial was undertaken in an ecologically valid environment measuring variables considered likely to be salient during hostile intent. The parameters examined in the field trial varied in a predictable manner and suggest that stressed individuals secrete a volatile steroid based marker that could form the basis for remote detection. Thus, overall the findings of this research provide a validated model of hostile intent that can be used by other researchers to test interventions aimed at detecting or deterring hostile intent.     

Ten challenges in computer-aided design

This short paper presents 10 challenging research areas in the general field of computer-aided design. The research problems come from the author's personal experience, and as such are highly subjective. All findings and opinions are those of the author and do not represent any of the institutions the author is affiliated with.     

Early release of proinflammatory cytokines after lung transplantation

BACKGROUND: Systemic hypotension may complicate the early postoperative period after lung transplantation. A release of proinflammatory cytokines secondary to lung ischemia/reperfusion injury could be involved in the pathogenesis of this early hemodynamic failure (EHF). Study objective: To assess prospectively whether the occurrence of EHF is associated with a release of cytokines in the systemic circulation. DESIGN: Blood samples were taken daily during the first postoperative week in 26 patients who underwent a double or a single-lung transplantation. These patients were divided into three groups: 7 patients who experienced EHF and subsequently died (EHF group); 15 patients without EHF (control group); and 4 patients without EHF but with an identified sepsis (sepsis group). The serum levels of interleukin (IL)-1beta, tumor necrosis factor-alpha (TNF-alpha), IL-6, and IL-8 were compared among the three groups. RESULTS: In the EHF group, the levels of each cytokine peaked at day 1 postoperatively. Cytokine levels at day 1 were significantly higher in the EHF group than in the control group (p<0.0006) or in the sepsis group (p<0.003 except for TNF-alpha). CONCLUSION: We conclude that EHF is associated with a massive release of proinflammatory cytokines that could play a determinant role in the pathogenesis of this complication.     

Geometrical illusions can affect time-to-contact estimation and mimed prehension.

Results indicate that under some conditions the Sander parallelogram illusion can affect time-to-contact (TTC) estimation in a prediction-motion (PM) task and in an interceptive action (IA). The illusion also affected mimed manual prehension. The implication is that the timing of responses in the PM and IA tasks may involve an estimate of TTC that is based on the perceived dimensions of the environment. Further research is warranted in the development of models of perceived collision and of visually guided actions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Constructing structural VAR models with conditional independence graphs

In this paper graphical modelling is used to select a sparse structure for a multivariate time series model of New Zealand interest rates. In particular, we consider a recursive structural vector autoregressions that can subsequently be described parsimoniously by a directed acyclic graph, which could be given a causal interpretation. A comparison between competing models is then made by considering likelihood and economic theory.     

Useful Computer Security

Usability is a growing concern in designing systems and applications that operate securely. Most usability work has focused on improving user interfaces, but security is systemic, and negotiating, instituting, and maintaining real-world security procedures and practices is an organizational and social activity.     

Frequency of Man‐Made Disasters in the 20th Century

This paper analyses two disaster databases maintained by the Center for Research on the Epidemiology of Disasters and by Emergency Management Australia. The objective is to quantify the frequency, nature and changes in man‐made disasters in industrialised countries during the past century. The analysis shows an exponential growth in disaster frequency, largely due to an increase in traditional hazards such as fires and explosions, rather than from new technologies. Although the number of incidents has grown, this has been offset by a decline in fatalities per incident. An important implication of these results is that regulatory oversight and internal corporate governance processes are inadequate to ensure effective management of modern industrial risks.