Uneven key pre-distribution scheme for multi-phase wireless sensor networks

In multi-phase Wireless Sensor Networks (WSNs), sensor nodes are redeployed periodically to replace nodes whose batteries are depleted. In order to keep the network resilient against node capture attacks across different deployment epochs, called generations, it is necessary to refresh the key pools from which cryptographic keys are distributed. In this paper, we propose Uneven Key Pre-distribution (UKP) scheme that uses multiple different key pools at each generation. Our UKP scheme provides self healing that improves the resiliency of the network at a higher level as compared to an existing scheme in the literature. Moreover, our scheme provides perfect local and global connectivity. We conduct our simulations in mobile environment to see how our scheme performs under more realistic scenarios

Scraping Airlines Bots: Insights Obtained Studying Honeypot Data

Airline websites are the victims of unauthorised online travel agencies and aggregators that use armies of bots to scrape prices and flight information. These so-called Advanced Persistent Bots (APBs) are highly sophisticated. On top of the valuable information taken away, these huge quantities of requests consume a very substantial amount of resources on the airlines' websites. In this work, we propose a deceptive approach to counter scraping bots. We present a platform capable of mimicking airlines' sites changing prices at will. We provide results on the case studies we performed with it. We have lured bots for almost 2 months, fed them with indistinguishable inaccurate information. Studying the collected requests, we have found behavioural patterns that could be used as complementary bot detection. Moreover, based on the gathered empirical pieces of evidence, we propose a method to investigate the claim commonly made that proxy services used by web scraping bots have millions of residential IPs at their disposal. Our mathematical models indicate that the amount of IPs is likely 2 to 3 orders of magnitude smaller than the one claimed. This finding suggests that an IP reputation-based blocking strategy could be effective, contrary to what operators of these websites think today

Uses and Abuses of Server-Side Requests

More and more web applications rely on server-side requests (SSRs) to fetch resources (such as images or even entire webpages) from user-provided URLs. As for many other web-related technologies, developers were very quick to adopt SSRs, even before their consequences for security were fully understood. In fact, while SSRs are simple to add from an engineering point of view, in this paper we show that—if not properly implemented—this technology can have several subtle consequences for security, posing severe threats to service providers, their users, and the Internet community as a whole. To shed some light on the risks of this communication pattern, we present the first extensive study of the security implication of SSRs. We propose a classification and four new attack scenarios that describe different ways in which SSRs can be abused to perform malicious activities. We then present an automated scanner we developed to probe web applications to identify possible SSR misuses. Using our tool, we tested 68 popular web applications and find that the majority can be abused to perform malicious activities, ranging from server-side code execution to amplification DoS attacks. Finally, we distill our findings into eight pitfalls and mitigations to help developers to implement SSRs in a more secure way

The additional value of patient-reported health status in predicting 1-year mortality after invasive coronary procedures: A report from the Euro Heart Survey on Coronary Revascularisation

Objective: Self-perceived health status may be helpful in identifying patients at high risk for adverse outcomes. The Euro Heart Survey on Coronary Revascularization (EHS-CR) provided an opportunity to explore whether impaired health status was a predictor of 1-year mortality in patients with coronary artery disease (CAD) undergoing angiographic procedures. Methods: Data from the EHS-CR that included 5619 patients from 31 member countries of the European Society of Cardiology were used. Inclusion criteria for the current study were completion of a self-report measure of health status, the EuroQol Questionnaire (EQ-5D) at discharge and information on 1-year follow-up, resulting in a study population of 3786 patients. Results: The 1-year mortality was 3.2% (n = 120). Survivors reported fewer problems on the five dimensions of the EQ-5D as compared with non-survivors. A broad range of potential confounders were adjusted for, which reached a p<0.10 in the unadjusted analyses. In the adjusted analyses, problems with self-care (OR 3.45; 95% CI 2.14 to 5.59) and a low rating (≤ 60) on health status (OR 2.41; 95% CI 1.47 to 3.94) were the most powerful independent predictors of mortality, among the 22 clinical variables included in the analysis. Furthermore, patients who reported no problems on all five dimensions had significantly lower 1-year mortality rates (OR 0.47; 95% CI 0.28 to 0.81). Conclusions: This analysis shows that impaired health status is associated with a 2-3-fold increased risk of all-cause mortality in patients with CAD, independent of other conventional risk factors. These results highlight the importance of including patients' subjective experience of their own health status in the evaluation strategy to optimise risk stratification and management in clinical practice

The Highway Technique: a new stenting technique to treat coronary bifurcation lesions

WOS: 000294133900012PubMed ID: 20142197Aims: We report a new stenting technique which was employed in 12 patients to treat coronary bifurcation lesions. Methods and results: A stent is positioned in the main vessel together with a balloon in the side branch, which is positioned slightly proximal to the main vessel stent that also has enough length to cover the side branch ostium. Both the stent in the main vessel and the balloon in the side branch are inflated simultaneously. Following deflation, a double lumen is created in the main vessel, proximal to the bifurcation. The stent balloon is removed with the side branch balloon left deflated in its initial position. The main vessel is rewired with a third guidewire. The side branch balloon and guidewire are removed. The initial guidewire in the main vessel is directed to the side branch. A balloon is advanced and inflated in the side branch to dilate the struts of the main vessel stent that will provide the side branch entrance. The side branch balloon is left in place. A size matched balloon is advanced on the third guidewire that was advanced in the main vessel and inflated inside the stent with high pressure. Finally, kissing balloon inflation is performed at the bifurcation. Provisional stenting of the side branch can be performed when necessary. Final kissing balloon inflation is recommended after stenting of the side branch. Conclusions: As a new coronary bifurcation stenting method, the Highway Technique has some advantages in side branch protection, with favourable immediate and 30-day clinical outcomes

How to estimate left ventricular hypertrophy in hypertensive patients

Left ventricular hypertrophy (LVH) is a structural remodeling of the heart developing as a response to volume and/or pressure overload. Previous studies have shown that hypertension is not an independent factor in the development of LVH and occurrence does not depend on the length and severity of hypertension, but the role played by other comorbidities such as triglycerides, age, gender, genetics, insulin resistance, obesity, physical inactivity, increased salt intake and chronic stress. LVH develops through three phases: adaptive, compensatory, and pathological phase. Contractile dysfunction is reversible in the first two phases and irreversible in the third. According to the Framingham study, LVH develops in 15-20% of patients with mild arterial hypertension, and in 50% of patients with severe hypertension. The pathophysiology of LVH includes hypertrophy of cardiomyocytes, interstitial and perivascular fibrosis, coronary microangiopathy and macroangiopathy. Individuals with LVH have 2-4 times higher risk of having adverse CV events compared to patients without LVH