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The proliferation of Internet of Things (IoT) systems is having a profound impact across all aspects of life. Recognising and identifying particular users is central to delivering the personalised experience that citizens want to experience, and that organisations wish to deliver. This article presents a survey of human-computer interaction-based (HCI-based) and natural habits-based behavioral biometrics that can be acquired unobtrusively through smart devices or IoT sensors for user recognition purposes. Robust and usable user recognition is also a security requirement for emerging IoT ecosystems to protect them from adversaries. Typically, it can be specified as a fundamental building block for most types of human-to-things accountability principles and access-control methods. However, end-users are facing numerous security and usability challenges in using currently available knowledge- and token-based recognition (i.e., authentication and identification) schemes. To address the limitations of conventional recognition schemes, biometrics, naturally come as a first choice to supporting sophisticated user recognition solutions. We perform a comprehensive review of touch-stroke, swipe, touch signature, hand-movements, voice, gait and footstep behavioral biometrics modalities. This survey analyzes the recent state-of-the-art research of these behavioral biometrics with a goal to identify their attributes and features for generating unique identification signatures. Finally, we present security, privacy, and usability evaluations that can strengthen the designing of robust and usable user recognition schemes for IoT applications.

The flow field of a chevron synthetic jet in impinging configuration at Reynolds number Re = 4500 , dimensionless stroke length L 0 / D = 28 and nozzle-to-plate distance H / D = 2 is experimentally investigated by means of Stereoscopic Particle Image Velocimetry. This study is motivated by the need of explaining the heat transfer behaviour of the chevron synthetic jet highlighting its differences with respect to the circular synthetic jet. Two different experiments are carried out. The first experiment is devoted to the characterisation of the flow field evolution on the impingement plate. The second experiment is a three-dimensional reconstruction of the entire flow field at three characteristic phases. The results show that the circular synthetic jet presents a circular velocity pattern on the plate, while the chevron exit leads to the acceleration of the fluid, thus to a larger impinging velocity with a star-shaped pattern. Furthermore, in both configurations a secondary vortex ring is formed on the wall at a radial position of about 2 diameters. For the circular synthetic jet, the intense turbulence levels are located in two annular regions: the inner region is due to the turbulent wall jet generated by the impinging trailing jet and the outer region is due to the effect of the generation of the secondary vortex ring. For the chevron synthetic jet, the intense turbulence level is produced by the turbulent wall jet along preferential paths. These preferential paths are caused by the star-shaped distribution of impinging velocity and the impinging streamwise coherent vortices. These features characterizing the impinging flow field are fundamental to understand and explain the mechanisms behind the heat transfer behaviour of such devices.

The objective of this study was to evaluate the local effect of the corpus luteum (CL) on ipsilateral oviduct-uterus functionality and early embryo development in ewes. A total of 499 embryos were transferred on Day 1 after in vitro fertilization into the ipsilateral (n = 250) and contralateral oviducts (n = 249) of 13 ewes on Day 1 after ovulation (18-20 embryos per oviduct). On Day 6, their reproductive tracts were collected and their uterine horns were flushed for embryo recovery. More recovered embryos, a higher proportion of blastocysts, and more viable embryos were collected when the embryos were transferred into the ipsilateral oviducts (P

Background The burden and characteristics of unplanned readmission after epilepsy-related discharge in children in the United States is not known. Methods We undertook a retrospective cohort study of children aged one to 17 years discharged after a nonelective hospitalization for epilepsy, sampled from the Healthcare Cost and Utilization Project’s 2013 and 2014 Nationwide Readmissions Database. Descriptive statistics and logistic regression models were used to examine the characteristics of initial hospitalization and risk factors for readmission. Results A total of 42,873 admissions for unique patients were identified, with 4470 (10.4%) leading to readmission within 30 days. The most common readmission diagnosis was epilepsy (24.9%). Neurodevelopmental diagnoses including cerebral palsy, intellectual disability, and developmental delay were associated with increased odds of readmission. Longer hospitalization, gastrostomy, and tracheostomy were also associated with readmission, but continuous electroencephalography use was not. Children insured by Medicare had a readmission rate of 34.4%, whereas there were no associations of readmission with other sociodemographic characteristics such as neighborhood, income, and sex. Conclusions Seizures are among the most frequent reasons for hospitalization in children. Establishing a benchmark readmission rate for pediatric epilepsy of 10.4% may be useful to health systems designing quality improvement efforts. Clinical factors were more strongly associated with readmission than demographic characteristics. Interventions to reduce pediatric epilepsy readmissions may have the highest yield when targeting children with neurodevelopmental comorbidities.

Urban horticulture (UH) has been proposed as a solution to increase urban sustainability, but the potential risks to human health due to potentially elevated soil heavy metals and metalloids (HM) concentrations represent a major constraint for UH expansion. Here we provide the first UK-wide assessment of soil HM concentrations (total and bioavailable) in UH soils and the factors influencing their bioavailability to crops. Soils from 200 allotments across ten cities in the UK were collected and analysed for HM concentrations, black carbon (BC) and organic carbon (OC) concentrations, pH and texture. We found that although HM are widespread across UK UH soils, most concentrations fell below the respective UK soil screening values (C4SLs): 99 % Cr; 98 % As, Cd, Ni; 95 % Cu; 52 % Zn. However, 83 % of Pb concentrations exceeded C4SL, but only 3.5 % were above Pb national background concentration of 820 mg kg−1. The bioavailable HM concentrations represent a small fraction (0.01–1.8 %) of the total concentrations even for those soils that exceeded C4SLs. There was a significant positive relationship between both total and bioavailable HM and soil BC and OC concentrations. This suggest that while contributing to the accumulation of HM concentrations in UH soils, BC and OC may also provide a biding surface for the bioavailable HM concentrations contributing to their immobilisation. These findings have implications for both management of the risk to human health associated with UH growing in urban soils and with management of UH soil. There is a clear need to understand the mechanisms driving soil-to-crop HM transfer in UH to improve potentially restrictive C4SL (e.g. Pb) especially as public demand for UH land is growing. In addition, the UH community would benefit from education programs promoting soil management practices that reduce the risk of HM exposure - particularly in those plots where C4SLs were exceeded.

An experimental investigation on the heat transfer enhancement achieved by impinging synthetic jets with vortex generators, in the form of chevron elements at the nozzle exit, is carried out. The heated thin foil heat transfer sensor is used in conjunction with the infrared thermography to measure the spatial distribution of the Nusselt number on the target plate. The heat transfer rates of impinging circular and chevron synthetic jets are compared under the same condition of cavity pressure. A parametric study on the effect of the dimensionless stroke length and the nozzle-to-plate distance on the heat transfer rates is carried out. For increasing dimensionless stroke length, at short nozzle-to-plate distances, the chevron synthetic jet reveals a star-shaped heat transfer pattern similar to that observed for an impinging continuous one. The results show that a chevron exit geometry can provide a significant heat transfer enhancement for relatively small nozzle-to-plate distances, up to a 20% increase with respect to the circular synthetic jet. At small dimensionless stroke lengths, such an enhancement is observed for a wide range of nozzle-to-plate distances.

Symptomatic metastatic spine disease (MSD), is a challenging disease involving 3%-20% of patients with bone metastases. Different surgical options are available and must be tailored to the general and neurologic conditions of the patients. Open kyphoplasty (OKP) refers to decompressive hemilaminectomy, associated with a contralateral percutaneous kyphoplasty, and in some cases, to a posterior stabilization. The aim of the study was to critically review our experience during the last decade with OKP in patients with cancer.Fifty-three patients with cancer underwent OKP for symptomatic MSD. The Tokuhashi score and Spinal Instability Neoplastic Score were calculated for each patient. Length of hospital stay, perioperative complications, incidence of adjacent-level fractures, and median survival after surgery were evaluated. Karnofsky Performance Status, visual analog scale, and Dennis Pain Score were calculated preoperatively, postoperatively, and at last follow-up.Median Tokuhashi score and Spinal Instability Neoplastic Score were 10 and 10, respectively. The mean volume of filling material inserted was 3.6 mL. Median operative time was 180 minutes. Complications included 8 leakages (15%), 2 permanent motor deficits (3.8%), and 2 asymptomatic pulmonary embolisms (3.8%). Mean length of hospital stay was 7 days. A significant improvement was observed in Karnofsky Performance Status, visual analog scale score, and Dennis Pain Score (P0.0001). Median follow-up was 16 months and overall survival 22 months.OKP was an effective treatment of symptomatic MSDs in selected oncologic patients with low Tokuhashi scores. It relieved lateral epidural compressions, expanded indications of palliative surgery in patients who were not otherwise surgical candidates, and rapidly dealt with cement leakages.

In this paper, we present a behavioral biometric-based smartphone user authentication mechanism, namely, AnswerAuth , which relies on the very common users’ behavior. Behavior, here, refers to the way a user slides the lock button on the screen, to unlock the phone, and brings the phone towards her ear. The authentication mechanism works with the biometric behavior based on the extracted features from the data recorded using the built-in smartphone sensors, i.e., accelerometer, gyroscope, gravity, magnetometer and touchscreen, while the user performed sliding and phone-lifting actions. We tested AnswerAuth on a dataset of 10,200 behavioral patterns collected from 85 users while they performed the unlocking actions, in sitting, standing, and walking postures, using six state-of-the-art conceptually different machine learning classifiers in two settings, i.e., with and without simultaneous feature selection and classification. Among all the chosen classifiers, Random Forest (RF) classifier proved to be the most consistent and accurate classifier on both full and reduced features and provided a True Acceptance Rate (TAR) as high as 99.35%. We prototype proof-of-the-concept Android app, based on our findings, and evaluate it in terms of security and usability. Security analysis of AnswerAuth confirms its robustness against the possible mimicry attacks. Similarly, the usability study based on Software Usability Scale (SUS) 1 questionnaire verifies the user-friendliness of the proposed scheme (SUS Score of 75.11). Experimental results prove AnswerAuth as a secure and usable authentication mechanism.

Information-Centric Networking (ICN) has emerged as a paradigm to cope with the increasing demand for content delivery on the Internet. In contrast to the Internet Protocol (IP), the underlying architecture of ICN enables users to request contents based on their name rather than their hosting location (IP address). On the one hand, this preserves users’ anonymity since packet routing does not require source and destination addresses of the communication parties. On the other hand, semantically-rich names reveal information about users’ interests, which poses serious threats to their privacy. A curious ICN node can monitor the traffic to profile users’ or censor specific contents for instance. In this paper, we present PrivICN: a system that enhances users privacy in ICN by protecting the confidentiality of content names and content data. PrivICN relies on a proxy encryption scheme and has several features that distinguish it from existing solutions: it preserves full in-network caching benefits, it does not require end-to-end communication between consumers and providers and it provides flexible user management (addition/removal of users). We evaluate PrivICN in a real ICN network (CCNx implementation) showing that it introduces an acceptable overhead and little delay. PrivICN is publicly available as an open-source library.