Introduction to the new usability

This paper introduces the motivation for and concept of the "new usability" and positions it against existing approaches to usability. It is argued that the contexts of emerging products and systems mean that traditional approaches to usability engineering and evaluation are likely to prove inappropriate to the needs of "digital consumers." The paper briefly reviews the contributions to this special issue in terms of their relation to the idea of the "new usability" and their individual approaches to dealing with contemporary usability issues. This helps provide a background to the "new usability" research agenda, and the paper ends by posing what are argued to be the central challenges facing the area and those which lie at the heart of the proposed research agenda

Poissonian communications : free space optical data transfer at the few-photon level

Communicating information at the few photon level typically requires some complexity in the transmitter or receiver in order to operate in the presence of noise. This in turn incurs expense in the necessary spatial volume and power consumption of the system. In this work we present a self-synchronised free-space optical communications system based on simple, compact and low power consumption semiconductor devices. A temporal encoding method, implemented using a gallium nitride micro-LED source and a silicon single photon avalanche photo-detector (SPAD) demonstrates data transmission at rates up to 100 kb/s for 8.25 pW received power, corresponding to 27 photons per bit. Furthermore, the signals can be decoded in the presence of both constant and modulated background noise at levels significantly exceeding the signal power. The systems low power consumption and modest electronics requirements are demonstrated employing it as a communications channel between two nano-satellite simulator systems

Rural-Urban Disparities in Emergency Department Intimate Partner Violence Resources

Objective: Little is known about availability of resources for managing intimate partner violence (IPV) at rural hospitals. We assessed differences in availability of resources for IPV screening and management between rural and urban emergency departments (EDs) in Oregon. Methods: We conducted a standardized telephone interview of Oregon ED directors and nurse managers on six IPV-related resources: official screening policies, standardized screening tools, public displays regarding IPV, on-site advocacy, intervention checklists and regular clinician education. We used chi-square analysis to test differences in reported resource availability between urban and rural EDs. Results: Of 57 Oregon EDs, 55 (96%) completed the survey. A smaller proportion of rural EDs, compared to urban EDs, reported official screening policies (74% vs. 100%, p=0.01), standardized screening instruments (21% vs. 55%, p=0.01), clinician education (38% vs. 70%, p=0.02) or on-site violence advocacy (44% vs. 95%, p<0.001). Twenty-seven percent of rural EDs had none or one of the studied resources, 50% had two or three, and 24% had four or more (vs. 0%, 35%, and 65% in urban EDs, p=0.003). Small, remote rural hospitals had fewer resources than larger, less remote rural hospitals or urban hospitals. Conclusion: Rural EDs have fewer resources for addressing IPV. Further work is needed to identify specific barriers to obtaining resources for IPV management that can be used in all hospital settings. [West J Emerg Med. 2011;12(2):178-183.

Book Reviews

Reproductive Biology and Phylogeny of Lizards and Tuatara. J. L. Rheubert, D. S. Siegel, and S. E. Trauth (Eds.). 2014. CRC Press. ISBN 9781466579866. 760 p. $143.96 (hardcover).— According to the authors, this book was intended to summarize the current knowledge of phylo- geny and reproduction of the Lepidosauria. I believe the authors have achieved their goal. Many of the chapters in this book are derived from presentations that took place at the Symposium on Reproductive Biology of Lizards at the Joint Meeting of Ichthyologists and Herpetologists held in Chattanooga, Tennessee in 2014. Although the majority of the authors are from the United States, the book includes authors from nine countries representing four continents and New Zealand. In the first chapter, Laurie Vitt states (p. 1), “It is difficult to imagine anything more interesting to biologists... than understanding the origins of reproductive patterns among lizards.” I agree. Vitt continues with the early history of topics such as seasonality of reproduction and fat storage, parthenogenesis, evolution of viviparity, placentation, and several other topics. For each of these topics, Vitt explains the origin of the field and the major researchers responsible for the insights and hypotheses in each field. His chapter ends with a call for natural history studies. In chapter two, John Wiens and Shea Lambert discuss the phylogeny of lizard families. They present a compelling argument for combining molecular and morphological data sets in phylogenetic studies. The authors admit that there are still many unresolved issues and more data are needed to fully understand the phylogeny of the lizards. In chapter three, Jose ́ Mart ́ın and Pilar Lo ́ pez define pheromone, discuss chemosensory abilities, and describe the role of pheromones in lizard reproduction. They present a list of studies on lizards and Tuatara, describe the source of chemicals, and the chemical nature of putative phero- mones. Mart ́ın and Lo ́pez conclude with the evolutionary origin of chemical signaling in lizards and a call for additional work on pheromone communication in lizards. Robert Cox and Atiel Kahrl discuss sexual selection and sexual dimorphism in lizards in chapter four. They include a list of studies and evaluate the data to determine what factors led to sexual dimorphism. They discuss intra- and intersexual selection. Cox and Kahrl discuss the ultimate cause and proximate mechanisms for sexual dimorphism and conclude with a discussion of the consequence of sexual selection on speciation and species recognition

Evidence Favoring Molybdenum−Carbon Bond Formation in Xanthine Oxidase Action: \u3csup\u3e17\u3c/sup\u3eO- and \u3csup\u3e13\u3c/sup\u3eC-ENDOR and Kinetic Studies

The reaction mechanism of the molybdoenzyme xanthine oxidase has been further investigated by 13C and 17O ENDOR of molybdenum(V) species and by kinetic studies of exchange of oxygen isotopes. Three EPR signal-giving species were studied:  (i) Very Rapid, a transient intermediate in substrate turnover, (ii) Inhibited, the product of an inhibitory side reaction with aldehyde substrates, and (iii) Alloxanthine, a species formed by reaction of reduced enzyme with the inhibitor, alloxanthine. The Very Rapid signal was developed either with [8-13C]xanthine or with 2-oxo-6-methylpurine using enzyme equilibrated with [17O]H2O. The Inhibited signal was developed with 2H13C2HO and the Alloxanthine signal by using [17O]H2O. Estimates of Mo−C distances were made, from the anisotropic components of the 13C-couplings, by corrected dipolar coupling calculations and by back-calculation from assumed possible structures. Estimated distances in the Inhibited and Very Rapid species were about 1.9 and less than 2.4 Å, respectively. A Mo−C bond in the Inhibited species is very strongly suggested, presumably associated with side-on bonding to molybdenum of the carbonyl of the aldehyde substrate. For the Very Rapid species, a Mo−C bond is highly likely. Coupling from a strongly coupled 17O, not in the form of an oxo group, and no coupling from other oxygens was detected in the Very Rapid species. No coupled oxygens were detected in the Alloxanthine species. That the coupled oxygen of the Very Rapid species is the one that appears in the product uric acid molecule was confirmed by new kinetic data. It is concluded that this oxygen of the Very Rapid species does not, as frequently assumed, originate from the oxo group of the oxidized enzyme. A new turnover mechanism is proposed, not involving direct participation of the oxo ligand group, and based on that of Coucouvanis et al. [Coucouvanis, D., Toupadakis, A., Lane, J. D., Koo, S. M., Kim, C. G., Hadjikyriacou, A. (1991) J. Am. Chem. Soc. 113, 5271−5282]. It involves formal addition of the elements of the substrate (e.g., xanthine) across the MoS double bond, to give a Mo(VI) species. This is followed by attack of a “buried” water molecule (in the vicinity of molybdenum and perhaps a ligand of it) on the bound substrate carbon, to give an intermediate that on intramolecular one-electron oxidation gives the Very Rapid species. The latter, in keeping with the 13C, 17O, and 33S couplings, is presumed to have the 8-CO group of the uric acid product molecule bonded side-on to molybdenum, with the sulfido molybdenum ligand retained, as in the oxidized enzyme

The Association between Emergency Department Resources and Diagnosis of Intimate Partner Violence

Objective: There is little information about which intimate partner violence (IPV) policies and services assist in the identification of IPV in the emergency department (ED). The objective of this study was to examine the association between a variety of resources and documented IPV diagnoses. Methods: Using billing data assembled from 21 Oregon EDs from 2001 to 2005, we identified patients assigned a discharge diagnosis of IPV. We then surveyed ED directors and nurse managers to gain information about IPV-related policies and services offered by participating hospitals. We combined billing data, survey results and hospital-level variables. Multivariate analysis assessed the likelihood of receiving a diagnosis of IPV depending on the policies and services available. Results: In 754,597 adult female ED visits, IPV was diagnosed 1,929 times. Mandatory IPV screening and victim advocates were the most commonly available IPV resources. The diagnosis of IPV was independently associated with the use of a standardized intervention checklist (OR 1.71, 95% CI 1.04-2.82). Public displays regarding IPV were negatively associated with IPV diagnosis (OR 0.56, 95% CI 0.35-0.88). Conclusions: IPV remains a rare documented diagnosis. Most common hospital-level resources did not demonstrate an association with IPV diagnoses; however, a standardized intervention checklist may play a role in clinicians\u27 likelihood diagnosing IPV

Taub--NUT Dyons in Heterotic String Theory

Starting with the Taub--NUT solution to Einstein's equations, together with a constant dilaton, a dyonic Taub--NUT solution of low energy heterotic string theory with non--trivial dilaton, axion and $U(1)$ gauge fields is constructed by employing $O(1,1)$ transformations. The electromagnetic dual of this solution is constructed, using SL(2,\rline) transformations. By an appropriate change to scaled variables, the extremal limit of the dual solution is shown to correspond to the low energy limit of an exact conformal field theory presented previously.Comment: 16 pages (plain TEX), (Revised version has curvature singularities correctly identified), IASSNS-HEP-94/50, McGill/94-2

Psychological Barriers to a Peaceful Resolution: Longitudinal Evidence from the Middle East and Northern Ireland

Does individual-level exposure to political violence prompt conciliatory attitudes? Does the answer vary by phase of conflict? The study uses longitudinal primary datasets to test the hypothesis that conflict-related experiences impact conciliation. Data were collected from Israeli Jews, Palestinians, and Protestants and Catholics in Northern Ireland. Across both contexts, and among both parties to each conflict, psychological distress and threat perceptions had a polarizing effect on conciliatory preferences. The study highlights that experiences of political violence are potentially a crucial source of psychological distress, and consequently, a continuing barrier to peace. This has implications in peacemaking, implying that alongside removing the real threat of violence, peacemakers must also work toward the social and political inclusion of those most affected by previous violence