Channel Impulse Response-based Distributed Physical Layer Authentication

In this preliminary work, we study the problem of {\it distributed} authentication in wireless networks. Specifically, we consider a system where multiple Bob (sensor) nodes listen to a channel and report their {\it correlated} measurements to a Fusion Center (FC) which makes the ultimate authentication decision. For the feature-based authentication at the FC, channel impulse response has been utilized as the device fingerprint. Additionally, the {\it correlated} measurements by the Bob nodes allow us to invoke Compressed sensing to significantly reduce the reporting overhead to the FC. Numerical results show that: i) the detection performance of the FC is superior to that of a single Bob-node, ii) compressed sensing leads to at least $20\%$ overhead reduction on the reporting channel at the expense of a small ($<1$ dB) SNR margin to achieve the same detection performance.Comment: 6 pages, 5 figures, accepted for presentation at IEEE VTC 2017 Sprin

Lafora Disease Masquerading as Hepatic Dysfunction

Lafora disease is fatal intractable progressive myoclonic epilepsy. It is frequently characterized by epileptic seizures, difficulty walking, muscle spasms, and dementia in late childhood or adolescence. We chronicle here an unusual case of an asymptomatic young male soccer player who presented with elevated liver enzymes. Neurological examination was unremarkable. The diagnostic workup for hepatitis, infectious etiologies, autoimmune disorders, hemochromatosis, Wilson\u27s disease, alpha-1 antitrypsin deficiency, and other related diseases was inconclusive. He subsequently underwent an uneventful percutaneous liver biopsy. Based on the pathognomonic histopathological findings, Lafora disease was considered the likely etiology. The present study is a unique illustration of this rare disorder initially manifesting with abnormal liver enzymes. It underscores the importance of clinical suspicion of Lafora disease in cases with unexplained hepatic dysfunction. Prompt liver biopsy and genetic testing should be performed to antedate the onset of symptoms in these patients

Silicon-mediated mitigation of wounding stress acts by up-regulating the rice antioxidant system

Silicon (Si) is essential for normal growth and development in plants and is also beneficial for their responses to wounding. However, the mechanisms by which Si acts to mitigate the effects of wounding is not fully understood. This effect possibly occurs through a reduction in the oxidative stresses associated with wounding. Here, we tested this possibility by investigating the effects of applying different concentrations of Si (0,5 and 1,0 mM) to rice plants under wounding stress for a period of 6 and 12 h. We found that a higher uptake of Si was signifiacntly associated with an increase in leaf chlorophyll contet. In response to wounding induced oxidative stress, the extent of lipid bilayer peroxidation was reduced in a dose-dependent manner by Si application for 6 or 12 h. Activity of the catalase enzyme was initially lowered by Si treatment; however, at 1.0 mM Si, catalase activity increased significantly after 12h of wounding stress. A similar response was also observed for a peroxidase enzyme. Polyphenol oxidase showed a significant reduction in activity. We conclude that Si application does not only improve leaf chlorophyll content but can also overcome the oxidative stress due wounds or physical injuries

Systematic review and meta-analysis of mortality and digoxin use in atrial fibrillation

Background: There is growing controversy regarding the association between digoxin and mortality in atrial fibrillation (AF). The aim of this analysis was to systematically review digoxin use and risk of mortality in patients with AF. Methods: MEDLINE, EMBASE, GoogleScholar, CINAHL, meeting abstracts, presentations, and Cochrane central databases were searched from inception through December 2014, without language restrictions. For a study to be selected, it had to report the risk of mortality associated with digoxin use in AF patients as an outcome measure. Data were extracted by 2 independent authors. Evidence tables were created. Results: A total of 16 studies (6 post hoc analyses of randomized controlled trials) with 111,978 digoxin users and 389,643 non-digoxin users were included. In a random effects model, patients treated with digoxin had a 27% increased risk of all-cause mortality (pooled HR 1.27; 95% CI 1.19–1.36) and 21% increased risk of cardiovascular mortality (pooled HR 1.21; 95% CI 1.12–1.30) compared with those who did not use digoxin. In a random effects model, the association of digoxin with all-cause mortality was stronger for AF patients without heart failure (pooled HR 1.47; 95% CI 1.25–1.73) than AF patients with heart failure (pooled HR 1.21; 95% CI 1.07–1.36, interaction p = 0.06). Conclusions: Digoxin use in AF is associated with increased risk of all-cause and cardiovascular mortalities. The effect size was larger for AF patients without heart failure than AF patients with heart failure. The study suggests further directed analyses to study the effect that is suggested by this meta-analysis, especially in AF without heart failure.

Countering Active Attacks on RAFT-based IoT Blockchain Networks

This paper considers an Internet of Thing (IoT) blockchain network consisting of a leader node and various follower nodes which together implement the RAFT consensus protocol to verify a blockchain transaction, as requested by a blockchain client. Further, two kinds of active attacks, i.e., jamming and impersonation, are considered on the IoT blockchain network due to the presence of multiple {\it active} malicious nodes in the close vicinity. When the IoT network is under the jamming attack, we utilize the stochastic geometry tool to derive the closed-form expressions for the coverage probabilities for both uplink and downlink IoT transmissions. On the other hand, when the IoT network is under the impersonation attack, we propose a novel method that enables a receive IoT node to exploit the pathloss of a transmit IoT node as its fingerprint to implement a binary hypothesis test for transmit node identification. To this end, we also provide the closed-form expressions for the probabilities of false alarm, missed detection and miss-classification. Finally, we present detailed simulation results that indicate the following: i) the coverage probability improves as the jammers' locations move away from the IoT network, ii) the three error probabilities decrease as a function of the link quality

Channel Impulse Response-based Physical Layer Authentication in a Diffusion-based Molecular Communication System

Consider impersonation attack by an active malicious nano node (Eve) on a diffusion based molecular communication (DbMC) system-Eve transmits during the idle slots to deceive the nano receiver (Bob) that she is indeed the legitimate nano transmitter (Alice). To this end, this work exploits the 3-dimensional (3D) channel impulse response (CIR) with L taps as device fingerprint for authentication of the nano transmitter during each slot. Specifically, Bob utilizes the Alice's CIR as ground truth to construct a binary hypothesis test to systematically accept/reject the data received in each slot. Simulation results highlight the great challenge posed by impersonation attack-i.e., it is not possible to simultaneously minimize the two error probabilities. In other words, one needs to tolerate on one error type in order to minimize the other error type

Matching-invariant running quark masses in Quantum Chromodynamics

The conventional quark mass is not continuous at thresholds. In this paper, we derive matchinginvariant quark masses which are continuous everywhere. They are expanded as an obvious function of the logarithmic Lambda scaled energy. The expansion coefficients are related to the original gamma and beta functions, with concretization to four loop level. The results show that the new expressions for the quark masses converge indeed much faster