Acoustic Integrity Codes: Secure Device Pairing Using Short-Range Acoustic Communication

Secure Device Pairing (SDP) relies on an out-of-band channel to authenticate devices. This requires a common hardware interface, which limits the use of existing SDP systems. We propose to use short-range acoustic communication for the initial pairing. Audio hardware is commonly available on existing off-the-shelf devices and can be accessed from user space without requiring firmware or hardware modifications. We improve upon previous approaches by designing Acoustic Integrity Codes (AICs): a modulation scheme that provides message authentication on the acoustic physical layer. We analyze their security and demonstrate that we can defend against signal cancellation attacks by designing signals with low autocorrelation. Our system can detect overshadowing attacks using a ternary decision function with a threshold. In our evaluation of this SDP scheme's security and robustness, we achieve a bit error ratio below 0.1% for a net bit rate of 100 bps with a signal-to-noise ratio (SNR) of 14 dB. Using our open-source proof-of-concept implementation on Android smartphones, we demonstrate pairing between different smartphone models.Comment: 11 pages, 11 figures. Published at ACM WiSec 2020 (13th ACM Conference on Security and Privacy in Wireless and Mobile Networks). Updated reference

Introduction to Special Section: Careers in Context

[Excerpt] Career scholars regularly cite Hughes’ (1937: 413) dictum that the study careers as “the moving perspective in which persons orient themselves with reference to the social order, and of the typical sequences and concatenations of office – may be expected to reveal the nature and \u27working constitution\u27 of a society.” Yet the greater part of the careers literature typically ignores this by focusing, largely, on the careers of individuals and influencing factors mainly linked to the person and his or her immediate context, to the neglect of the broader context within which the careers are lived. However, large-scale economic and organizational changes that have affected most industrial societies in recent decades – the rising amount of business activity across national borders (Anderson & Cavanaugh, 2005), the increasingly global arena for entertainment and media, the influence of the internet in economic, social and political affairs, increased labor force participation by women and concomitant changes in family roles, and the emergence of distinctive forms of employment relations across countries (Whitley, 1999; Barley & Kunda, 2004) – make neglect of the social and political contexts in which careers unfold very problematic. These developments have reshaped the multitude of settings in which work careers are lived: the communities of organizations, occupations, geographical areas, and so on. Specifically, the broad social context that provides the canvas on which work careers are painted, rather than the immediate organizational context as discussed, for example, by Johns (2001), is an important, yet partly neglected factor for understanding work careers. The immediate context may, of course, form a link between career and the broader context. However, it is the latter and not the former type of context that is a primary object of interest in this respect. We suggest that research exploring the broad context within which work careers are lived helps us understand better the nature of career in an Internet-based, globalised economy and how these careers, in turn, influence developments in the context

Suitability of Different PCR-DGGE Primer Sets for the Monitoring of Lactic Acid Bacteria in Wine

Lactic acid bacteria (LAB) play a dual role in winemaking as they are the main effectors of malolactic fermentation, but some members can also cause wine spoilage. PCR-DGGE has proved to be a quick tool to study the LAB community and their fluctuation in wine. For detecting wine-associated LAB by PCR-DGGE, the primer sets WLAB1/WLAB2GC, WBAC1/WBAC2GC, Lac1/Lac1o/Lac2GC, 341fGC/518r and rpoB1/rpoB1o/rpoB2GC were tested and evaluated in this study. The primer systems were assessed by the separation of LAB reference strains on DGGE gels and by attributing the resulting amplicons to defined species. Subsequently, the detection of LAB in wine samples and enrichments thereof was compared. While the primer systems WBAC1/WBAC2GC and 341fGC/518r were not appropriate, the Lac1/Lac1o/Lac2GC primer set performed well. However, multiple bands complicated the evaluation. The rpoB1/rpoB1o/rpoB2GC set seemed to be promising for the detection of LAB in wine, although further improvements in terms of the detection limit need to be done. Due to the pronounced sensitivity and the sufficient discrimination of LAB at species level, the WLAB1/WLAB2GC primer system was found to be most suitable for studying the occurrence of LAB in wine

Solid solution hardening of vacancy stabilized TixW1−xB2

AbstractWe present a combined experimental and theoretical investigation of sputter deposited thin films in the ternary system Ti1−xWxB2. Solid solutions of Ti1−xWxB2−z were prepared by physical vapor deposition (PVD) and, over the whole composition range, found to crystallize in the AlB2 structure type. The obtained films exhibit good thermal stability and high hardness, evidencing a maximum value of almost 40GPa for Ti0.67W0.33B2−z. The effect of vacancies on stabilization and mechanical properties of the AlB2 structure type is discussed, using ab initio simulations. Based on our results, we can conclude that vacancies are crucial for the phase stability of PVD deposited Ti1−xWxB2−z coatings

A synthesis: what works to deliver optimal health outcomes for uk care home residents

The detailed reviews, interviews and subsequent longitudinal case studies structured around a unifying realist analytical framework allowed us to establish a theory of commissioning for health care provision to care homes which proposes health services will work better when: staff are explicitly tasked to work with care homes at an institutional level as well as individual residents; healthcare and care home staff are empowered to co-design their working models; where explicit expertise in dementia care is available; the role of GP as a medical care provider is supported by access to a wider array of services; and they incorporate care management. There was no evidence from our study that a short term focus on avoiding admissions to acute hospitals from care homes added any value to service specification or care delivery

Platinum recycling going green via induced surface potential alteration enabling fast and efficient dissolution

The recycling of precious metals, for example, platinum, is an essential aspect of sustainability for the modern industry and energy sectors. However, due to its resistance to corrosion, platinum-leaching techniques rely on high reagent consumption and hazardous processes, for example, boiling aqua regia; a mixture of concentrated nitric and hydrochloric acid. Here we demonstrate that complete dissolution of metallic platinum can be achieved by induced surface potential alteration, an 'electrode-less' process utilizing alternatively oxidative and reductive gases. This concept for platinum recycling exploits the so-called transient dissolution mechanism, triggered by a repetitive change in platinum surface oxidation state, without using any external electric current or electrodes. The effective performance in non-toxic low-concentrated acid and at room temperature is a strong benefit of this approach, potentially rendering recycling of industrial catalysts, including but not limited to platinum-based systems, more sustainable