5,265 research outputs found

    Side Channel Anomaly Detection in Industrial Control Systems Using Physical Characteristics of End Devices

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    Industrial Control Systems (ICS) are described by the Department of Homeland Security as systems that are so \vital to the United States that their incapacity or destruction would have a debilitating impact on our physical or economic security. Attacks like Stuxnet show that these systems are vulnerable. The end goal for Stuxnet was to spin centrifuges at a frequency rate outside of normal operation and hide its activity from the ICS operator. This research aims to provide a proof of concept for an anomaly detection system that would be able to detect an attack like Stuxnet by measuring the physical change in vibration caused by the attack. The attack can hide what is reported to the operator, but it cannot hide the physical changes caused by the attack. This research uses a piezoelectric vibration sensor to collect vibration data coming from a centrifugal pump and ow meter on an ICS training system at each operating level. The collected data is then fingerprinted and classified using established RF-DNA techniques to determine if it can differentiate between the vibrations produced at each of the operating level. A clear differentiation between operating levels indicates that an ADS is feasible

    Localized Blood Occlusion Generation in an In-Vitro Circulatory Catheter System

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    Hydrocephalus is a debilitating neurological disorder that involves the accumulation of cerebrospinal fluid in a ventricle of the brain. The implantation of a catheter commonly treats hydrocephalus with drainage. These catheters have a short lifespan due to obstruction from biological materials. Shunt systems have an extremely high failure rate of more than 40% failed within 1 year and up to 85% failed within 10 years. Previously, polymer-based flexible implantable magnetic micro-actuators were developed to clean up the catheter by mechanical vibration. We have demonstrated clearing of bacteria attachment and are proceeding to examine clearing effects on larger clotting materials, such as blood clots. A benchtop in-vivo blood circulatory system was created to simulate flow conditions. To prove device viability there must be a succinctly created, localized, consistent occlusion of the catheter. Targeted outcomes include clotting within a 20-30 minute time frame, consistent pressure at occlusion, and controlled clot location. Fibrin was applied to control the location of the clotting and to accelerate the occlusion. Contributing factors that were examined are the method of fibrin application, blood density, and protamine sulfate application. Testing has shown the necessity of blood density of 50% or higher for occlusion. Blood tested at 10% density rarely clotted. In comparison of differing fibrin coating applications, an externally supported coating was found to occlude within the desired parameters at the highest rate of any tested method and was found to be the most reliable method with 60% of tests occluding before 30 minutes and 80% occluding

    A novel tool to measure extracellular glutamate in the Zebrafish nervous system in vivo

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    Glutamate is the major excitatory neurotransmitter in the brain. Its release and eventual recycling are key to rapid sustained neural activity. We have paired the gfap promoter region with the glutamate reporter molecule, iGluSnFR, to drive expression in glial cells throughout the nervous system. Tg(gfap:iGluSnFR) is expressed on the glial membrane of Müller glia cells in the retina, which rapidly respond to stimulation and the release of extracellular glutamate. As glial cells are associated with most, if not all, synapses, Tg(gfap:iGluSnFR) is a novel and exciting tool to measure neuronal activity and extracellular glutamate dynamics in many regions of the nervous system. Glutamate is the major excitatory neurotransmitter in the brain. Its release and eventual recycling are key to rapid sustained neural activity.1 Glial cells play a key role in the uptake and recycling of glutamate from the synaptic cleft. iGluSnFR has been used to study synaptic activity by measuring glutamate dynamics in the zebrafish nervous system.2,3 Previous work has also used iGluSnFR in glial cells; however, this was done transiently in the mouse using viral vectors.2,4 As such, we designed a transgene to stably express iGluSnFR in the glial cells of the zebrafish nervous system. We report a novel transgenic zebrafish, Tg(gfap:iGluSnFR), that displays the glutamate-sensitive fluorescent reporter iGluSnFR specifically on the membrane of glial cells (Figure 1A–C). This molecule is expressed on the glial membrane in many brain regions and rapidly responds to stimulation and the release of extracellular glutamate (Figure 1D–F, Supplementary Data; Supplementary Data are available online at www.liebertpub.com/zeb). Thus, pairing the sensitivity of iGluSnFR and optical transparency of the zebrafish provides a powerful tool for understanding glutamate dynamics in neural tissues in vivo

    Cues and knowledge structures used by mental-health professionals when making risk assessments

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    Background: Research into mental-health risks has tended to focus on epidemiological approaches and to consider pieces of evidence in isolation. Less is known about the particular factors and their patterns of occurrence that influence clinicians’ risk judgements in practice. Aims: To identify the cues used by clinicians to make risk judgements and to explore how these combine within clinicians’ psychological representations of suicide, self-harm, self-neglect, and harm to others. Method: Content analysis was applied to semi-structured interviews conducted with 46 practitioners from various mental-health disciplines, using mind maps to represent the hierarchical relationships of data and concepts. Results: Strong consensus between experts meant their knowledge could be integrated into a single hierarchical structure for each risk. This revealed contrasting emphases between data and concepts underpinning risks, including: reflection and forethought for suicide; motivation for self-harm; situation and context for harm to others; and current presentation for self-neglect. Conclusions: Analysis of experts’ risk-assessment knowledge identified influential cues and their relationships to risks. It can inform development of valid risk-screening decision support systems that combine actuarial evidence with clinical expertise

    Global Disease Outbreaks Associated with the 2015–2016 El Niño Event

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    Interannual climate variability patterns associated with the El Niño-Southern Oscillation phenomenon result in climate and environmental anomaly conditions in specific regions worldwide that directly favor outbreaks and/or amplification of variety of diseases of public health concern including chikungunya, hantavirus, Rift Valley fever, cholera, plague, and Zika. We analyzed patterns of some disease outbreaks during the strong 2015–2016 El Niño event in relation to climate anomalies derived from satellite measurements. Disease outbreaks in multiple El Niño-connected regions worldwide (including Southeast Asia, Tanzania, western US, and Brazil) followed shifts in rainfall, temperature, and vegetation in which both drought and flooding occurred in excess (14–81% precipitation departures from normal). These shifts favored ecological conditions appropriate for pathogens and their vectors to emerge and propagate clusters of diseases activity in these regions. Our analysis indicates that intensity of disease activity in some ENSO-teleconnected regions were approximately 2.5–28% higher during years with El Niño events than those without. Plague in Colorado and New Mexico as well as cholera in Tanzania were significantly associated with above normal rainfall (p \u3c 0.05); while dengue in Brazil and southeast Asia were significantly associated with above normal land surface temperature (p \u3c 0.05). Routine and ongoing global satellite monitoring of key climate variable anomalies calibrated to specific regions could identify regions at risk for emergence and propagation of disease vectors. Such information can provide sufficient lead-time for outbreak prevention and potentially reduce the burden and spread of ecologically coupled diseases

    Bottomonium from lattice QCD as a probe of the Quark-Gluon Plasma

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    We study the temperature dependence of bottomonium for temperatures in the range 0.4Tc < T < 2.1Tc, using non-relativistic dynamics for the bottom quark and full relativistic lattice QCD simulations for Nf = 2 light flavors. We consider the behaviour of the correlators in Euclidean space, we analyze the associated spectral functions and we study the dependence on the momentum. Our results are amenable to a successful comparison with effective field theories. They help build a coherent picture of the behaviour of bottomonium in the plasma, consistent which the current LHC results

    Bottomonium from lattice QCD as a probe of the Quark-Gluon Plasma

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    We study the temperature dependence of bottomonium for temperatures in the range 0.4Tc < T < 2.1Tc, using non-relativistic dynamics for the bottom quark and full relativistic lattice QCD simulations for Nf = 2 light flavors. We consider the behaviour of the correlators in Euclidean space, we analyze the associated spectral functions and we study the dependence on the momentum. Our results are amenable to a successful comparison with effective field theories. They help build a coherent picture of the behaviour of bottomonium in the plasma, consistent which the current LHC results
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