The Dimensions of Driver Performance during Secondary Manual Tasks

This analysis identified the underlying dimensions of driver performance using data obtained from drivers engaged in secondary manual tasks. Randomly chosen subjects balanced for age and gender used one of five advanced navigation and communication systems while driving on a closed roadway. Fifteen driver performance variables were averaged and standardized across subjects for 79 tasks. There were high correlations between all variables. Principal Component Analysis (PCA) found that the vector of loadings defining the first principal component (PC1) was positive for all 15 variables, accounting for 61 percent of the total variation across all tasks. It is interpreted as overall driver demand. PC2 loaded with one sign on event detection and response variables, but opposing sign on visual-manual workload variables. It identified tasks making drivers more inattentive to outside events than expected, given a task’s visual-manual workload, and accounted for 17 percent of total variation. It is interpreted as low-workloadbut-high-inattentiveness. PC3 had loadings of opposing sign for peripheral vs. central event variables (5 percent of total variation). It is interpreted as peripheral insensitivity. The first three components together accounted for 83 percent of total variation, which is deemed substantial. Thus most of the information available through the 15 original variables can be summarized by only three PC variables. Because the vectors of loadings defining the components are orthogonal to each other as defined by PCA, no single variable by itself can capture all the important variations in driver performance during secondary manual tasks. A multivariate design and analysis is required

A Bibliography of Early Secular American Music-18th Century(Book Rerview)

published or submitted for publicatio

Towards Operationalizing Driver Distraction

Driver distraction has been the subject of much research interest and scientific inquiry. Operationalizing driver distraction is a complex task—one that is necessary for advancing both science and public policy in this domain. While many operational definitions can be gathered from the literature, gaps are common. In order to fill such gaps, 21 experts reviewed 55 driver distraction definitions in the literature. Aided by the results of a pre-workshop questionnaire the experts narrowed these definitions. The Regan et al. (2011) definition of driver distraction was agreed to at a workshop. Subsidiary terms related to this definition were defined to improve clarity and applicability of the definition. It is hoped that a consistent and agreed definition of driver distraction and its associated terms will advance scientific progress in understanding and measuring driver distraction

Validation of the Static Load Test for Event Detection During Hands-Free Conversation

Objective. To see if visual event reaction times (RTs) during handsfree conversation conditions in the Enhanced Static Load Test (ESLT) can predict RTs in similar conditions in on-road driving. Methods. Brake reaction times to random center and side light events were measured while watching a driving video, attempting to keep a marker in the center of the lane with a steering wheel, answering the phone by pressing a button, and carrying on neutral or angry handsfree conversations in covert (silent) or overt mode on a hands-free phone device. Open-road tests were conducted in traffic for subjects with similar side and front light events, with foot reaction times measured while engaged in the same secondary tasks and conditions. Results. Mean RTs for the task segments in the lab were predictive of the mean RTs for the corresponding task segments in the on-road test (r = 0.90, df = 16, p \u3c 0.000001). Conclusion. This study validates the Enhanced Static Load Test as predictive of visual event RTs during open-road driving for the range of experimental conditions and tasks considered

2-[1-(1-Naphth­yl)-1H-1,2,3-triazol-4-yl]pyridine

In the crystal structure of the title compound, C17H12N4, the angle between the naphthalene and 1H-1,2,3-triazole ring systems is 71.02 (4)° and that between the pyridine and triazole rings is 8.30 (9)°

Heterosexual HIV-1 infectiousness and antiretroviral use : systematic review of prospective studies of discordant couples

Background: Recent studies have estimated the reduction in HIV-1 infectiousness with antiretroviral therapy (ART), but high-quality studies such as randomized controlled trials, accompanied by rigorous adherence counseling, are likely to overestimate the effectiveness of treatment-as-prevention in real-life settings. Methods: We attempted to summarize the effect of ART on HIV transmission by undertaking a systematic review and meta-analysis of HIV-1 infectiousness per heterosexual partnership (incidence rate and cumulative incidence over study follow-up) estimated from prospective studies of discordant couples. We used random-effects Poisson regression models to obtain summary estimates. When possible, the analyses were further stratified by direction of transmission (man-to-woman or woman-to-man) and economic setting (high- or low-income countries). Potential causes of heterogeneity of estimates were explored through subgroup analyses. Results: Fifty publications were included. Nine allowed comparison between ART and non-ART users within studies (ART-stratified studies), in which summary incidence rates were 3.6/100 person-years (95% confidence interval = 2.0-6.5) and 0.2/100 person-years (0.07-0.7) for non-ART- and ART-using couples, respectively (P < 0.001), constituting a 91% (79-96%) reduction in per-partner HIV-1 incidence rate with ART use. The 41 studies that did not stratify by ART use provided estimates with high levels of heterogeneity (I2 statistic) and few reported levels of ART use, making interpretation difficult. Nevertheless, estimates tended to be lower with ART use. Infectiousness tended to be higher for low-income than high-income settings, but there was no clear pattern by direction of transmission (man-to-woman and woman-to-man). Conclusions: ART substantially reduces HIV-1 infectiousness within discordant couples, based on observational studies, and could play a major part in HIV-1 prevention efforts. However, the non-zero risk from partners receiving ART demonstrates that appropriate counseling and other risk-reduction strategies for discordant couples are still required. Additional estimates of ART effectiveness by adherence level from real-life settings will be important, especially for persons starting treatment early without symptoms

Ernst Freund as Precursor of the Rational Study of Corporate Law

Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe

Vinculin phosphorylation differentially regulates mechanotransduction at cell–cell and cell–matrix adhesions

Vinculin phosphorylation on residue Y822 is necessary for cell stiffening in response to tension on cadherins but not integrins.Cells experience mechanical forces throughout their lifetimes. Vinculin is critical for transmitting these forces, yet how it achieves its distinct functions at cell–cell and cell–matrix adhesions remains unanswered. Here, we show vinculin is phosphorylated at Y822 in cell–cell, but not cell–matrix, adhesions. Phosphorylation at Y822 was elevated when forces were applied to E-cadherin and was required for vinculin to integrate into the cadherin complex. The mutation Y822F ablated these activities and prevented cells from stiffening in response to forces on E-cadherin. In contrast, Y822 phosphorylation was not required for vinculin functions in cell–matrix adhesions, including integrin-induced cell stiffening. Finally, forces applied to E-cadherin activated Abelson (Abl) tyrosine kinase to phosphorylate vinculin; Abl inhibition mimicked the loss of vinculin phosphorylation. These data reveal an unexpected regulatory mechanism in which vinculin Y822 phosphorylation determines whether cadherins transmit force and provides a paradigm for how a shared component of adhesions can produce biologically distinct functions