Electrocardiogram-based biometrics for user identification - Using your heartbeat as a digital key.

External biometrics such as thumbprint and facial recognition have become standard tools for securing our digital devices and protecting our data. These systems, however, are potentially prone to copying and cybercrime access. Researchers have therefore explored internal biometrics, such as the electrical patterns within an electrocardiogram (ECG). The heart's electrical signals carry sufficient distinctiveness to allow the ECG to be used as an internal biometric for user authentication and identification. Using the ECG in this way has many potential advantages and limitations. This article reviews the history of ECG biometrics and explores some of the technical and security considerations. It also explores current and future uses of the ECG as an internal biometric.

What Proportion of People Who Try One Cigarette Become Daily Smokers? A Meta-Analysis of Representative Surveys.

Introduction: The "conversion rate" from initial experimentation to daily smoking is a potentially important metric of smoking behavior, but estimates of it based on current representative data are lacking. Methods: The Global Health Data Exchange was searched for representative surveys conducted in English speaking, developed countries after the year 2000 that included questions about ever trying a cigarette and ever smoking daily. The initial search identified 2776 surveys that were further screened for language, location, year, sample size, survey structure, and representativeness. Forty-four surveys that passed the screening process were accessed, and their codebooks were examined to see whether the two questions of interest were included. Eight datasets allowed extraction or estimation of relevant information. Survey quality was assessed with regards to response rates, sampling methods, and data collection procedures. PRISMA guidelines were followed, with explicit rules for approaching derived variables and skip patterns. Proportions were pooled using random effects meta-analysis. Results: The eight surveys used representative samples of the general adult population. Response rates varied from 45% to 88%. Survey methods were on par with the best practice in this field. Altogether, 216314 respondents were included of whom 60.3% (95% CI = 51.3 to 69.3) ever tried a cigarette. Among them, 68.9% (95% CI = 60.9 to 76.9%) progressed to daily smoking. Conclusions: Over two-thirds of people who try one cigarette become, at least temporarily, daily smokers. The finding provides strong support for the current efforts to reduce cigarette experimentation among adolescents. Implications: The transition from trying the first cigarette through occasional to daily smoking usually implies that a recreational activity is turning into a compulsive need that has to be satisfied virtually continuously. The "conversion rate" from initial experimentation to daily smoking is thus a potentially important metric of smoking behavior, but estimates of it based on representative data are lacking. The present meta-analysis addressed this gap. Currently, about two-thirds of nonsmokers experimenting with cigarettes progress to daily smoking. The finding supports strongly the current efforts to reduce cigarette experimentation among adolescents.

Biotin-, fluorescein- and 'clickable' conjugates of phospha-oseltamivir as probes for the influenza virus which utilize selective binding to the neuraminidase.

The synthesis of conjugates of phospha-oseltamivir to the well established reporter groups fluorescein and biotin and an approach to multimeric inhibitors is described. We report powerful inhibition of the influenza neuraminidase by these probes and quantify fluorescence quenching during binding of the fluorescein conjugate through titration with the neuraminidase. Thus, we show that they could be useful tools to efficiently inhibit, detect and quantify the virus and the neuraminidase in biological systems.