1,542 research outputs found
Replacing Gas Permeable Lenses: The Benefit of a Professional in Office Dispense
Replacing Gas Permeable Lenses: The Benefit of a Professional in Office Dispens
Classifying network attack scenarios using an ontology
This paper presents a methodology using network attack ontology to classify computer-based attacks. Computer network attacks differ in motivation, execution and end result. Because attacks are diverse, no standard classification exists. If an attack could be classified, it could be mitigated accordingly. A taxonomy of computer network attacks forms the basis of the ontology. Most published taxonomies present an attack from either the attacker's or defender's point of view. This taxonomy presents both views. The main taxonomy classes are: Actor, Actor Location, Aggressor, Attack Goal, Attack Mechanism, Attack Scenario, Automation Level, Effects, Motivation, Phase, Scope and Target. The "Actor" class is the entity executing the attack. The "Actor Location" class is the Actorâs country of origin. The "Aggressor" class is the group instigating an attack. The "Attack Goal" class specifies the attackerâs goal. The "Attack Mechanism" class defines the attack methodology. The "Automation Level" class indicates the level of human interaction. The "Effects" class describes the consequences of an attack. The "Motivation" class specifies incentives for an attack. The "Scope" class describes the size and utility of the target. The "Target" class is the physical device or entity targeted by an attack. The "Vulnerability" class describes a target vulnerability used by the attacker. The "Phase" class represents an attack model that subdivides an attack into different phases. The ontology was developed using an "Attack Scenario" class, which draws from other classes and can be used to characterize and classify computer network attacks. An "Attack Scenario" consists of phases, has a scope and is attributed to an actor and aggressor which have a goal. The "Attack Scenario" thus represents different classes of attacks. High profile computer network attacks such as Stuxnet and the Estonia attacks can now be been classified through the âAttack Scenarioâ class
Location and mapping of 2.4 GHz RF transmitters
This paper describes the use of a MetaGeek WiSpy dongle in conjunction with custom developed client-server software for the accurate identication of Wireless nodes within an organisation. The MetaGeek WiSpy dongle together with the custom developed software allow for the determination of the positions of Wi-Fi transceivers to within a few meters, which can be helpful in reducing the area for physical searches in the event of rogue units. This paper describes the tool and methodology for a site survey as a component that can be used in organisations wishing to audit their environments for wireless networks. The tool produced from this project, the WiSpy Signal Source Mapping Tool, is a three part application based on a client-server architecture. One part interfaces with a low cost 2.4 GHz spectrum analyser, another stores the data collected from all the spectrum analysers and the last part interprets the data to provide a graphical overview of the Wi-Fi network being analysed. The location of the spectrum analysers are entered as GPS points, and the tool can interface with a GPS device to automatically update its geographical location. The graphical representation of the 2.4 GHz spectrum populated with Wi-Fi devices (Wi-Fi network) provided a fairly accurate method in locating and tracking 2.4 GHz devices. Accuracy of the WiSpy Signal Source Mapping Tool is hindered by obstructions or interferences within the area or non line of sight
Bandwidth management and monitoring for IP network traffic : an investigation
Bandwidth management is a topic which is often discussed, but on which relatively little work has been done with regard to compiling a comprehensive set of techniques and methods for managing traffic on a network. What work has been done has concentrated on higher end networks, rather than the low bandwidth links which are commonly available in South Africa and other areas outside the United States. With more organisations increasingly making use of the Internet on a daily basis, the demand for bandwidth is outstripping the ability of providers to upgrade their infrastructure. This resource is therefore in need of management. In addition, for Internet access to become economically viable for widespread use by schools, NGOs and other academic institutions, the associated costs need to be controlled. Bandwidth management not only impacts on direct cost control, but encompasses the process of engineering a network and network resources in order to ensure the provision of as optimal a service as possible. Included in this is the provision of user education. Software has been developed for the implementation of traffic quotas, dynamic firewalling and visualisation. The research investigates various methods for monitoring and management of IP traffic with particular applicability to low bandwidth links. Several forms of visualisation for the analysis of historical and near-realtime traffic data are also discussed, including the use of three-dimensional landscapes. A number of bandwidth management practices are proposed, and the advantages of their combination, and complementary use are highlighted. By implementing these suggested policies, a holistic approach can be taken to the issue of bandwidth management on Internet links
A framework for the application of network telescope sensors in a global IP network
The use of Network Telescope systems has become increasingly popular amongst security researchers in recent years. This study provides a framework for the utilisation of this data. The research is based on a primary dataset of 40 million events spanning 50 months collected using a small (/24) passive network telescope located in African IP space. This research presents a number of differing ways in which the data can be analysed ranging from low level protocol based analysis to higher level analysis at the geopolitical and network topology level. Anomalous traffic and illustrative anecdotes are explored in detail and highlighted. A discussion relating to bogon traffic observed is also presented. Two novel visualisation tools are presented, which were developed to aid in the analysis of large network telescope datasets. The first is a three-dimensional visualisation tool which allows for live, near-realtime analysis, and the second is a two-dimensional fractal based plotting scheme which allows for plots of the entire IPv4 address space to be produced, and manipulated. Using the techniques and tools developed for the analysis of this dataset, a detailed analysis of traffic recorded as destined for port 445/tcp is presented. This includes the evaluation of traffic surrounding the outbreak of the Conficker worm in November 2008. A number of metrics relating to the description and quantification of network telescope configuration and the resultant traffic captures are described, the use of which it is hoped will facilitate greater and easier collaboration among researchers utilising this network security technology. The research concludes with suggestions relating to other applications of the data and intelligence that can be extracted from network telescopes, and their use as part of an organisationâs integrated network security system
Mapping the location of 2.4 GHz transmitters to achieve optimal usage of an IEEE 802.11 network
This paper describes the use of a low cost 2.4 GHz spectrum analyser, the MetaGeek WiSpy device, in conjunction with custom developed client-server software for the accurate identification of 2.4 GHz transmitters within a given area. The WiSpy dongle together with the custom developed software allow for determination of the positions of Wi-Fi transmitters to within a few meters, which can be helpful in reducing the work load for physical searches in the process of surveying the Wi-Fi network and geographical area. This paper describes the tool and methodology for a site survey as a component that can be used in organisations wishing to audit their environments for Wi-Fi networks. The tool produced from this project, the WiSpy Signal Source Mapping Tool, is a three part application based on a client-server architecture. One part interfaces with a low cost 2.4 GHz spectrum analyser, another stores the data collected from all the spectrum analysers and the third part interprets the data to provide a graphical overview of the Wi-Fi network being analysed. The location of the spectrum analysers are entered as GPS points, and the tool can interface with a GPS device to automatically update its geographical location. The graphical representation of the 2.4 GHz spectrum populated with Wi-Fi devices (Wi-Fi network) provided a fairly accurate method in locating and tracking 2.4 GHz devices. Accuracy of the WiSpy Signal Source Mapping Tool is hindered by obstructions, interferences within the area or non line of sight
Testing the Effects of Automated Navigation in a General Population Web Survey
This study investigates how an auto-forward design, where respondents navigate through a web survey automatically, affects response times and navigation behavior in a long mixed-device web survey. We embedded an experiment in a health survey administered to the general population in The Netherlands to test the auto-forward design against a manual-forward design. Analyses are based on detailed paradata that keep track of the respondentsâ behavior in navigating the survey. We find that an auto-forward design decreases compleÂtion times and that questions on pages with automated navigation are answered significantÂly faster compared to questions on pages with manual navigation. However, we also find that respondents use the navigation buttons more in the auto-forward condition compared to the manual-forward condition, largely canceling out the reduction in survey duration. Furthermore, we also find that the answer options 'I don't know' and 'I rather not say' are used just as often in the auto-forward condition as in the manual-forward condition, indiÂcating no differences in satisficing behavior. We conclude that auto-forwarding can be used to reduce completing times, but we also advice to carefully consider mixing manual and auto-forwarding within a survey
Targeting LOXL2 for cardiac interstitial fibrosis and heart failure treatment
Interstitial fibrosis plays a key role in the development and progression of
heart failure. Here, we show that an enzyme that crosslinks collagenâLysyl
oxidase-like 2 (Loxl2)âis essential for interstitial fibrosis and mechanical
dysfunction of pathologically stressed hearts. In mice, cardiac stress
activates fibroblasts to express and secrete Loxl2 into the interstitium,
triggering fibrosis, systolic and diastolic dysfunction of stressed hearts.
Antibody-mediated inhibition or genetic disruption of Loxl2 greatly reduces
stress-induced cardiac fibrosis and chamber dilatation, improving systolic and
diastolic functions. Loxl2 stimulates cardiac fibroblasts through PI3K/AKT to
produce TGF-ÎČ2, promoting fibroblast-to-myofibroblast transformation; Loxl2
also acts downstream of TGF-ÎČ2 to stimulate myofibroblast migration. In
diseased human hearts, LOXL2 is upregulated in cardiac interstitium; its
levels correlate with collagen crosslinking and cardiac dysfunction. LOXL2 is
also elevated in the serum of heart failure (HF) patients, correlating with
other HF biomarkers, suggesting a conserved LOXL2-mediated mechanism of human
HF
Why we should understand the patient experience: clinical empathy and medicines optimisation
Objectives
To critically discuss the need for pharmacists to underpin their consultations with appropriate âclinical empathyâ as part of effective medicines optimisation.
Methods
Use of literature around empathy, consultation and pharmacy practice to develop a case for greater clinical empathy in pharmacy consultations.
Key findings
Clinical empathy is defined from the literature and applied to pharmacy consultations, with a comparison to empathy in other clinical professions. Historical barriers to the embedding of clinical empathy into pharmacy consultations are also explored.
Conclusions
We challenge the pharmacy profession to consider how clinical empathy should underpin consultations with a series of introspective questions and provide some sample questions to support pharmacy consultations. We also make the case for appropriate education and professional development of consultation skills at undergraduate and postgraduate level. We contend that patientsâ relationships with practitioners are critical, and a lack of empathy can impact the effectiveness of care
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