595 research outputs found
Tracking advanced persistent threats in critical infrastructures through opinion dynamics
Advanced persistent threats pose a serious issue for modern industrial environments, due to their targeted and complex attack vectors that are difficult to detect. This is especially severe in critical infrastructures that are accelerating the integration of IT technologies. It is then essential to further develop effective monitoring and response systems that ensure the continuity of business to face the arising set of cyber-security threats. In this paper, we study the practical applicability of a novel technique based on opinion dynamics, that permits to trace the attack throughout all its stages along the network by correlating different anomalies measured over time, thereby taking the persistence of threats and the criticality of resources into consideration. The resulting information is of essential importance to monitor the overall health of the control system and cor- respondingly deploy accurate response procedures. Advanced Persistent Threat Detection Traceability Opinion Dynamics.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Preventing Advanced Persistent Threats in Complex Control Networks
An Advanced Persistent Threat (APT) is an emerging attack against Industrial Control and Automation Systems, that is executed over a long period of time and is difficult to detect. In this context, graph theory can be applied to model the interaction among nodes and the complex attacks affecting them, as well as to design recovery techniques that ensure the survivability of the network. Accordingly, we leverage a decision model to study how a set of hierarchically selected nodes can collaborate to detect an APT within the network, concerning the presence of changes in its topology. Moreover, we implement a response service based on redundant links that dynamically uses a secret sharing scheme and applies a flexible routing protocol depending on the severity of the attack. The ultimate goal is twofold: ensuring the reachability between nodes despite the changes and preventing the path followed by messages from being discovered.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Gynecomastia during imatinib mesylate treatment for gastrointestinal stromal tumor: a rare adverse event
<p>Abstract</p> <p>Background</p> <p>Imatinib mesylate has been the standard therapeutic treatment for chronic myeloid leukemia, advanced and metastatic gastrointestinal stromal tumor (GIST). It is well tolerated with mild adverse effects. Gynecomastia development during the course of treatment has been rarely reported.</p> <p>Methods</p> <p>Ninety-eight patients with advanced or recurrent GIST were treated with imatinib mesylate. Among the fifty-seven male patients six developed gynecomastia during the treatment. The lesions were confirmed by sonography. Sex hormone levels were determined in six patients with and without the presence of gynecomastia respectively. The patients with gynecomatia were treated with tamoxifene and the sex hormones were assayed before and after tamoxifene treatment.</p> <p>Results</p> <p>In patients with gynecomastia the lump underneath the bilateral nipples was 2.5 to 5 centimeters in diameter. Their serum free testosterone levels ranged between 356.61 and 574.60 ng/dl with a mean ± SD of 408.64 ± 82.06 ng/dl (95% CI 343.03~474.25 ng/dl), which is within the normal range. The level of serum estradiol was 42.89 ± 16.54 pg/ml (95% CI 29.66~56.12 pg/ml). Three patients had higher levels (43.79~71.21 pg/ml) and the others' were within normal range of 27.00~34.91 pg/ml. Six patients without the development of gynecomastia had normal free testosterone. One patient died because of large tumor burden. The sex hormones had no significant changes before and after tamoxifene treatment.(<it>P </it>> 0.05)</p> <p>Conclusions</p> <p>Testosterone levels were not decreased in the six GIST patients with gynecomastia. Three patients had increased serum estradiol level which suggests that imbalance of sex hormones may be the cause of gynecomastia during treatment with imatinib mesylate.</p
Comparison of the in vitro invasive capabilities of Plasmodium falciparum schizonts isolated by Percoll gradient or using magnetic based separation
<p>Abstract</p> <p>Background</p> <p>Percoll gradient centrifugation is often used for synchronization, enrichment, or isolation of a particular stage of <it>Plasmodium falciparum</it>. However, Percoll, a hyperosmotic agent, may have harmful effects on the parasites. Magnetic bead column (MBC) separation has been used as an alternative. This is a report of a head-to-head comparison of the <it>in vitro </it>invasive capabilities of parasites isolated by either of the two methods.</p> <p>Methods</p> <p>The <it>P. falciparum </it>laboratory strain isolate 7G8 was grown <it>in vitro </it>using standard procedures and synchronized using 5% sorbitol. On separate days when the schizont parasitaemia was >1%, the culture was split and half was processed by Percoll gradient centrifugation and the other half by magnetic bead column separation. Both processed parasites were placed back in culture and allowed to invade new uninfected erythrocytes.</p> <p>Results</p> <p>In 10 paired assays, the mean efficiency of invasion of 7G8 parasites treated by Percoll gradient centrifugation was 35.8% that of those treated by magnetic bead column separation (95% CI, p = 0.00067) A paired <it>t </it>test with two tails was used for these comparisons.</p> <p>Conclusions</p> <p>In this comparison, magnetic bead column separation of 7G8 schizonts resulted in higher viability and efficiency of invasion than utilizing Percoll gradient centrifugation.</p
Enhancing security and dependability of industrial networks with opinion dynamics
Opinion Dynamics poses a novel technique to accurately locate the patterns of an advanced attack against an industrial infrastructure, compared to traditional intrusion detection systems. This distributed solution provides pro table information to identify the most a ected areas within the network, which can be leveraged to design and deploy tailored response mechanisms that ensure the continuity of the service. In this work, we base on this multi-agent collaborative approach to propose a response technique that permits the secure delivery of messages across the network. For such goal, our contribution is twofold: rstly, we rede ne the existing algorithm to assess not only the compromise of nodes, but also the security and quality of service of communication links; secondly, we develop a routing protocol that prioritizes the secure paths throughout
the topology considering the information obtained from the detection system.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tec
A four-helix bundle stores copper for methane oxidation
Methane-oxidising bacteria (methanotrophs) require large quantities of copper for the membrane-bound (particulate) methane monooxygenase (pMMO). Certain methanotrophs are also able to switch to using the iron-containing soluble MMO (sMMO) to catalyse methane oxidation, with this switchover regulated by copper. MMOs are Nature’s primary biological mechanism for suppressing atmospheric levels of methane, a potent greenhouse gas. Furthermore, methanotrophs and MMOs have enormous potential in bioremediation and for biotransformations producing bulk and fine chemicals, and in bioenergy, particularly considering increased methane availability from renewable sources and hydraulic fracturing of shale rock. We have discovered and characterised a novel copper storage protein (Csp1) from the methanotroph Methylosinus trichosporium OB3b that is exported from the cytosol, and stores copper for pMMO. Csp1 is a tetramer of 4-helix bundles with each monomer binding up to 13 Cu(I) ions in a previously unseen manner via mainly Cys residues that point into the core of the bundle. Csp1 is the first example of a protein that stores a metal within an established protein-folding motif. This work provides a detailed insight into how methanotrophs accumulate copper for the oxidation of methane. Understanding this process is essential if the wide-ranging biotechnological applications of methanotrophs are to be realised. Cytosolic homologues of Csp1 are present in diverse bacteria thus challenging the dogma that such organisms do not use copper in this location
Design of a Novel Multifunction Decision Support Display for Anesthesia Care: AlertWatch® OR
Radiological evaluation of colorectal anastomoses
Background and aims: The purpose of this study was to determine the accuracy, interobserver variability, timing and discordance with relaparotomy of postoperative radiological examination of colorectal anastomoses. Patient/methods: From 2000 to 2005, 429 patients underwent an
Medicines information and adherence in HIV/AIDS patients
Background: Providing written medicines information is being legislated in an increasing number of countries worldwide, with the patient information leaflet (PIL) being the most widely used method for conveying health information. The impact of providing such information on adherence to therapy is reportedly unpredictable. Therapy for human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) and related opportunistic infections usually involves polytherapy and complex regimens, both of which are risk factors for non-adherence. The objective of this study was to assess the impact of medicines information on adherence to chronic co-trimoxazole therapy in low-literate HIV/AIDS patients. Methods: Two different PILs were designed for co-trimoxazole tablets and were available in both English and isiXhosa. Participants were randomly allocated to a control group (receiving no PIL), group A (receiving a 'complex PIL') and group B (receiving a 'simple PIL' incorporating pictograms). At the first interview, demographic data were collected and the time, date and day that the participant would take his/her first tablet of the month's course was also documented. In a follow-up interview adherence to therapy was assessed using two methods; self-report and tablet count. Results: The medicines information materials incorporating simple text and pictograms resulted in significantly improved adherence to therapy in the short term, whereas a non-significant increase in adherence was associated with the availability of the more complex information. This was shown by both the self-reported assessment as well as the tablet count. Conclusion: This research suggests that appropriately designed written material can have a positive impact in improving adherence and, together with verbal consultation, are essential for enabling patients to make appropriate decisions about their medicine taking
A modified evidence-based practice- knowledge, attitudes, behaviour and decisions/outcomes questionnaire is valid across multiple professions involved in pain management
- …