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

2015 Building a Grad Nation Report: Progress and Challenge in Ending the High School Dropout Epidemic

This sixth annual report to the nation highlights the significant progress that has been made, but also the serious challenges that remain – closing gaping graduation gaps between various student populations; tackling the challenge in key states and school districts; and keeping the nation's focus on ensuring that all students – whom Robert Putnam calls "our kids" – have an equal chance at the American Drea

On Deception-Based Protection Against Cryptographic Ransomware

In order to detect malicious file system activity, some commercial and academic anti-ransomware solutions implement deception-based techniques, specifically by placing decoy files among user files. While this approach raises the bar against current ransomware, as any access to a decoy file is a sign of malicious activity, the robustness of decoy strategies has not been formally analyzed and fully tested. In this paper, we analyze existing decoy strategies and discuss how they are effective in countering current ransomware by defining a set of metrics to measure their robustness. To demonstrate how ransomware can identify existing deception-based detection strategies, we have implemented a proof-of-concept anti-decoy ransomware that successfully bypasses decoys by using a decision engine with few rules. Finally, we discuss existing issues in decoy-based strategies and propose practical solutions to mitigate them

Establishing a sensitive fluorescence-based quantification method for cyclic nucleotides

BACKGROUND: Approximately 40% of prescribed drugs exert their activity via GTP-binding protein-coupled receptors (GPCRs). Once activated, these receptors cause transient changes in the concentration of second messengers, e.g., cyclic adenosine 3′,5′-monophosphate (cAMP). Specific and efficacious genetically encoded biosensors have been developed to monitor cAMP fluctuations with high spatial and temporal resolution in living cells or tissue. A well characterized biosensor for cAMP is the Förster resonance energy transfer (FRET)-based Epac1-camps protein. Pharmacological characterization of newly developed ligands acting at GPCRs often includes numerical quantification of the second messenger amount that was produced. RESULTS: To quantify cellular cAMP concentrations, we bacterially over-expressed and purified Epac1-camps and applied the purified protein in a cell-free detection assay for cAMP in a multi-well format. We found that the biosensor can detect as little as 0.15 pmol of cAMP, and that the sensitivity is not impaired by non-physiological salt concentrations or pH values. Notably, the assay tolerated desiccation and storage of the protein without affecting Epac1-camps cyclic nucleotide sensitivity. CONCLUSIONS: We found that determination cAMP in lysates obtained from cell assays or tissue samples by purified Epac1-camps is a robust, fast, and sensitive assay suitable for routine and high throughput analyses

Improving Secure Device Insertion in Home Ad Hoc Networks

Home ad-hoc networks are sets of devices that interact to offer enhanced services to the users. These networks are heterogeneous, dynamic and fully decentralized. Moreover, they generally lack of a skilled administrator. These properties dramatically reduce the efficiency of classical security approaches: even defining the boundaries of such networks can be difficult. Ways to solve this problem where recently found, using the concept of secure long-term communities. Solutions rely on one critical operation: the secure insertion of a device in the home ad-hoc network. In this paper, we propose two ways to improve this operation, using store-and-forward techniques. The first improvement deals with the ability to realize insertion under loose connectivity circumstances. The other improvement deals with the ability for the user to use any trusted device in order to realize insertion. Keywords: Network Security, Key-management

Why Tenth Graders Fail to Finish High School: A Dropout Typology Latent Class Analysis

A large percentage of the students who drop out of K-12 schools in the United States do so at the end of high school, at some point after grade 10. Yet we know little about the differences between different types of students who drop out of the end of high school. The purpose of this study is to examine a typology of high school dropouts from a large nationally representative dataset (ELS:2002) using latent class analysis (LCA). We found three significantly different types of dropouts; Quiet, Jaded, and Involved. Based on this typology of three subgroups, we discuss implications for future dropout intervention research, policy, and practice

Dissecting CD8+ T cell pathology of severe SARS-CoV-2 infection by single-cell immunoprofiling

Introduction: SARS-CoV-2 infection results in varying disease severity, ranging from asymptomatic infection to severe illness. A detailed understanding of the immune response to SARS-CoV-2 is critical to unravel the causative factors underlying differences in disease severity and to develop optimal vaccines against new SARS-CoV-2 variants. Methods: We combined single-cell RNA and T cell receptor sequencing with CITE-seq antibodies to characterize the CD8+ T cell response to SARS-CoV-2 infection at high resolution and compared responses between mild and severe COVID-19. Results: We observed increased CD8+ T cell exhaustion in severe SARS-CoV-2 infection and identified a population of NK-like, terminally differentiated CD8+ effector T cells characterized by expression of FCGR3A (encoding CD16). Further characterization of NK-like CD8+ T cells revealed heterogeneity among CD16+ NK-like CD8+ T cells and profound differences in cytotoxicity, exhaustion, and NK-like differentiation between mild and severe disease conditions. Discussion: We propose a model in which differences in the surrounding inflammatory milieu lead to crucial differences in NK-like differentiation of CD8+ effector T cells, ultimately resulting in the appearance of NK-like CD8+ T cell populations of different functionality and pathogenicity. Our in-depth characterization of the CD8+ T cell-mediated response to SARS-CoV-2 infection provides a basis for further investigation of the importance of NK-like CD8+ T cells in COVID-19 severity.</p

Affiliation-Hiding Authentication with Minimal Bandwidth Consumption

Part 3: Lightweight AuthenticationInternational audienceAffiliation-Hiding Authentication (AHA) protocols have the seemingly contradictory property of enabling users to authenticate each other as members of certain groups, without revealing their affiliation to group outsiders. Of particular interest in practice is the group-discovering variant, which handles multiple group memberships per user. Corresponding solutions were only recently introduced, and have two major drawbacks: high bandwidth consumption (typically several kilobits per user and affiliation), and only moderate performance in scenarios of practical application.While prior protocols have O(n2) time complexity, where n denotes the number of affiliations per user, we introduce a new AHA protocol running in O(nlogn) time. In addition, the bandwidth consumed is considerably reduced. We consider these advances a major step towards deployment of privacy-preserving methods in constraint devices, like mobile phones, to which the economization of these resources is priceless