67 research outputs found

    Toward Scalable Docker-Based Emulations of Blockchain Networks

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    Blockchain, like any other technology, needs a strong testing methodology to support its evolution. Setting up meaningful blockchain tests is a notoriously complex task for several reasons: software is complex, large number of nodes are involved, network is non ideal, etc. Developers usually adopts small virtual laboratories or costly real devnets, based on real software. Researchers usually prefer simulations of a large number of nodes, based on simplified models. In this paper, we aim to obtain the advantages of both approaches, i.e., performing large, realistic, unexpensive, and flexible experiments, using real blockchain software within a virtual environment. To do that, we tackle the challenge of running large blockchain networks in a single physical machine, leveraging Linux and Docker. We analyze a number of problems that arise when large blockchain networks are emulated and we provide technical solutions for all of them. Finally, we describe our experience of emulating a fairly large blockchain network, comprising more than 3000 containers, for research purposes

    Experimental Investigation and Lumped-parameter Model of the Cooling System of an ICE under Nucleate Boiling Conditions

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    Abstract The work presents the results of experimental tests, which were carried out on a small-displacement spark ignition engine, where a low flow rate electric pump was used to substitute the standard crankshaft-driven one. The engine was then operated both under usual single-phase heat transfer regime and under nucleate boiling conditions. The engine was properly instrumented in order to record coolant pressure, temperature and flow rate as well as metal temperatures. The experimental investigation was coupled with the development of a dynamic lump-parameter model of the engine cooling system. The model calculates the spatial averaged metal temperature, the engine-out coolant temperature and the fraction of metal heat transfer area which is involved in nucleate boiling as a function of engine-in coolant flow rate, pressure and temperature, fuel mass flow rate and engine speed. The experimental data and the model results show a good agreement and the model is suitable to develop a coolant flow rate control system. This facilitates faster engine warm-up, lower fuel consumption and lower CO 2 emissions, which can be significant under low-load and cold-start conditions

    The future of Cybersecurity in Italy: Strategic focus area

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    This volume has been created as a continuation of the previous one, with the aim of outlining a set of focus areas and actions that the Italian Nation research community considers essential. The book touches many aspects of cyber security, ranging from the definition of the infrastructure and controls needed to organize cyberdefence to the actions and technologies to be developed to be better protected, from the identification of the main technologies to be defended to the proposal of a set of horizontal actions for training, awareness raising, and risk management

    Frailty and post-operative delirium influence on functional status in patients with hip fracture: the GIOG 2.0 study

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    Background: This study analyzes the effect of frailty and Post-Operative Delirium (POD) on the functional status at hospital discharge and at 4-month follow-up in patients with hip fracture (HF). Methods: Multicenter prospective observational study of older patients with HF admitted to 12 Italian Orthogeriatric centers (July 2019-August 2022). POD was assessed using the 4AT. A 26-item Frailty Index (FI) was created using data collected on admission. The outcome measures were Cumulated Ambulation Score (CAS) ≤ 2 at discharge and a telephone-administered CAS ≤ 2 after 4 months. Poisson regression models were used to assess the effect of frailty and POD on outcomes. Results: 984 patients (median age 84 years, IQR = 79–89) were recruited: 480 (48.7%) were frail at admission, 311 (31.6%) developed POD, and 158 (15.6%) had both frailty and POD. In a robust Poisson regression, frailty alone (Relative Risk, RR = 1.56, 95% Confidence Intervals, CI 1.19–2.04, p = 0.001) and its combination with POD (RR = 2.57, 95% CI 2.02–3.26, p < 0.001) were associated with poor functional status at discharge. At 4-month follow-up, the combination of frailty with POD (RR 3.65, 95% CI 1.85–7.2, p < 0.001) increased the risk of poor outcome more than frailty alone (RR 2.38, 95% CI 1.21–4.66, p < 0.001). Conclusions: POD development exacerbates the negative effect that frailty exerts on functional outcomes in HF patients

    Sustained Na<sup>+</sup>/H<sup>+</sup> exchanger activation promotes gliotransmitter release from reactive hippocampal astrocytes following oxygen-glucose deprivation

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    Hypoxia ischemia (HI)-related brain injury is the major cause of long-term morbidity in neonates. One characteristic hallmark of neonatal HI is the development of reactive astrogliosis in the hippocampus. However, the impact of reactive astrogliosis in hippocampal damage after neonatal HI is not fully understood. In the current study, we investigated the role of Na +/H+ exchanger isoform 1 (NHE1) protein in mouse reactive hippocampal astrocyte function in an in vitro ischemia model (oxygen/glucose deprivation and reoxygenation, OGD/REOX). 2 h OGD significantly increased NHE1 protein expression and NHE1-mediated H+ efflux in hippocampal astrocytes. NHE1 activity remained stimulated during 1-5 h REOX and returned to the basal level at 24 h REOX. NHE1 activation in hippocampal astrocytes resulted in intracellular Na+ and Ca2+ overload. The latter was mediated by reversal of Na+/Ca2+ exchange. Hippocampal astrocytes also exhibited a robust release of gliotransmitters (glutamate and pro-inflammatory cytokines IL-6 and TNFα) during 1-24 h REOX. Interestingly, inhibition of NHE1 activity with its potent inhibitor HOE 642 not only reduced Na+ overload but also gliotransmitter release from hippocampal astrocytes. The noncompetitive excitatory amino acid transporter inhibitor TBOA showed a similar effect on blocking the glutamate release. Taken together, we concluded that NHE1 plays an essential role in maintaining H + homeostasis in hippocampal astrocytes. Over-stimulation of NHE1 activity following in vitro ischemia disrupts Na+ and Ca2+ homeostasis, which reduces Na+-dependent glutamate uptake and promotes release of glutamate and cytokines from reactive astrocytes. Therefore, blocking sustained NHE1 activation in reactive astrocytes may provide neuroprotection following HI. © 2014 Cengiz et al

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    USBCaptchaIn: Preventing (un)conventional attacks from promiscuously used USB devices in industrial control systems

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    Industrial Control Systems (ICS) are sensible targets for high profile attackers and advanced persistent threats, which are known to exploit USB thumb drives as an effective spreading vector. In ICSes, thumb drives are widely used to transfer files among disconnected systems and represent a serious security risks, since, they may be promiscuously used in both critical and regular systems. The threats come both from malware hidden in files stored in the thumb drives and from BadUSB attacks. BadUSB leverages the modification of firmware of USB devices in order to mimic the behaviour of a keyboard and send malicious commands to the host. We present a solution that allows a promiscuous use of USB thumbs drives while protecting critical machines from malware, that spreads by regular file infection or by firmware infection. The main component of the architecture we propose is an hardware, called USBCaptchaIn, intended to be in the middle between critical machines and connected USB devices. We do not require users to change the way they use thumb drives. To avoid human-errors, we do not require users to take any decision. The proposed approach is highly compatible with already deployed products of a ICS environment and proactively blocks malware before they reach their targets. We describe our solution, provide a thorough analysis of the security of our approach in the ICS context, and report the informal feedback of some experts regarding our first prototypes

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    Automated configuration and measurement of emulated networks with AutoNetkit

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    Simon Knigh

    Pipeline-integrity: Scaling the use of authenticated data structures up to the cloud

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    Public cloud storage services are widely adopted for their scalability and low cost. However, delegating the management of the storage has serious implications from the security point of view. We focus on integrity verification of query results based on the use of Authenticated Data Structures (ADS). An ADS enables efficient updates of a cryptographic digest, when data changes, and efficient query verification against this digest. Since, the digest can be updated (and usually signed)exclusively with the intervention of a trusted party, the adoption of this approach is source of a serious performance degradation, in particular when the trusted party is far from the server that stores the ADS. In this paper, we show a protocol for a key–value storage service that provides ADS-enabled integrity-protected queries and updates without impairing scalability, even in the presence of large network latencies between trusted clients and an untrusted server. Our solution complies with the principle of the cloud paradigm in which services should be able to arbitrarily scale with respect to number of clients, requests rates, and data size keeping response time limited. We formally prove that our approach is able to detect server misbehaviour in a setting whose consistency rules are only slightly weaker than those guaranteed by previous results. We provide experimental evidence for the feasibility and scalability of our approach
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