| 1. |
- Almgren, Magnus, 1972, et al.
(författare)
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A Comparison of Alternative Audit Sources for Web Server Attack Detection
- 2007
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Ingår i: The 12th Nordic Workshop on Secure IT-systems.
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Konferensbidrag (refereegranskat)abstract
- Most intrusion detection systems available today are usinga single audit source for detecting all attacks, eventhough attacks have distinct manifestations in differentparts of the system. In this paper we carry out a theoretical investigation of the role of the audit source for the detection capability of the intrusion detection system (IDS). Concentrating on web server attacks, we examine the attack manifestations available to intrusiondetection systems at different abstraction layers, includinga network-based IDS, an application-based IDS, andfinally a host-based IDS.Our findings include that attacks indeed have differentmanifestations depending on the audit source used. Someaudit sources may lack any manifestation for certain attacks, and, in other cases contain only events that are indirectly connected to the attack in question. This, in turn, affects the reliability of the attack detection if the intrusion detection system uses only a single audit source for collecting security-relevant events. Hence, we conclude that using a multisource detection model increases the probability of detecting a range of attacks directed toward the web server. We also note that this model should account for the detection quality of each attack / audit stream to be able to rank alerts.Keywords: intrusion detection, attack manifestations
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| 2. |
- Almgren, Magnus, 1972, et al.
(författare)
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A Multi-Sensor Model to Improve Automated Attack Detection
- 2008
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Ingår i: 11th International Symposium, RAID 2008, Cambridge, MA, USA, September 15-17, 2008. Lecture Notes in Computer Science. - 9783540874027 ; 5230/2008, s. 291-310
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Konferensbidrag (refereegranskat)abstract
- Most intrusion detection systems available today are using a single audit source for detection, even though attacks have distinct manifestations in different parts of the system. In this paper we investigate how to use the alerts from several audit sources to improve the accuracy of the intrusion detection system (IDS). Concentrating on web server attacks, we design a theoretical model to automatically reason about alerts from different sensors, thereby also giving security operators a better understanding of possible attacks against their systems. Our model takes sensor status and capability into account, and therefore enables reasoning about the absence of expected alerts. We require an explicit model for each sensor in the system, which allows us to reason about the quality of information from each particular sensor and to resolve apparent contradictions in a set of alerts.Our model, which is built using Bayesian networks, needs some initial parameter values that can be provided by the IDS operator. We apply this model in two different scenarios for web server security. The scenarios show the importance of having a model that dynamically can adapt to local transitional traffic conditions, such as encrypted requests, when using conflicting evidence from sensors to reason about attacks.
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| 3. |
- Aulchenko, Yurii S, et al.
(författare)
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Loci influencing lipid levels and coronary heart disease risk in 16 European population cohorts
- 2009
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 41:1, s. 47-55
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Tidskriftsartikel (refereegranskat)abstract
- Recent genome-wide association (GWA) studies of lipids have been conducted in samples ascertained for other phenotypes, particularly diabetes. Here we report the first GWA analysis of loci affecting total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglycerides sampled randomly from 16 population-based cohorts and genotyped using mainly the Illumina HumanHap300-Duo platform. Our study included a total of 17,797-22,562 persons, aged 18-104 years and from geographic regions spanning from the Nordic countries to Southern Europe. We established 22 loci associated with serum lipid levels at a genome-wide significance level (P < 5 x 10(-8)), including 16 loci that were identified by previous GWA studies. The six newly identified loci in our cohort samples are ABCG5 (TC, P = 1.5 x 10(-11); LDL, P = 2.6 x 10(-10)), TMEM57 (TC, P = 5.4 x 10(-10)), CTCF-PRMT8 region (HDL, P = 8.3 x 10(-16)), DNAH11 (LDL, P = 6.1 x 10(-9)), FADS3-FADS2 (TC, P = 1.5 x 10(-10); LDL, P = 4.4 x 10(-13)) and MADD-FOLH1 region (HDL, P = 6 x 10(-11)). For three loci, effect sizes differed significantly by sex. Genetic risk scores based on lipid loci explain up to 4.8% of variation in lipids and were also associated with increased intima media thickness (P = 0.001) and coronary heart disease incidence (P = 0.04). The genetic risk score improves the screening of high-risk groups of dyslipidemia over classical risk factors.
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| 4. |
- Enoksson, Emmi
(författare)
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Studies on image control for better reproduction in offset
- 2006
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This research work has focused on studies of image control for better reproduction in offset and has been applied practically. This research work has resulted in a survey of color management knowledge, a communication list concerning ICC profiles, an educational kit, a proposal for a new terminology and a patent concerning image adaptation. The work is divided into following three areas: 1) image classification A better understanding of image processing can avoid misunderstandings in the print and leading to more satisfied customers. To achieve optimal print quality for different images, it is important to adapt the prepress settings to the image category. Images can be divided into different categories depending on their image content, key information and tone distribution. Trials have been carried out in which the IT.8 test chart has been adapted to different image categories. The results of the image adaptation suggest that an adjustment only to low-key images (dark images) is sufficient, as even normal-key images then show a better similarity to the original image. The low-key image showed more details in dark areas. 2) color separation Two studies has been carried out. The purpose has been to investigate the knowledge level in color separation, the use of ICC-profiles and the understanding of color management in various printing houses in Sweden. This was done to identify and suggest new applications and suggested actions. These studies indicate that there is a serious problem in the graphic arts industry. The problem is that there is both an insufficient knowledge of color management and a lack of communication. There is a lack of competence and a lack of literature and instructions which can help printers to better understand the technology, and communication suffers through a lack of a common language. 3) suggested actions and the development of tools Terminology simplification is crucial for the users. A new term for separation “Compensation by Black”, CB, has been suggested. A single term should make it easier for the users to understand and use the different settings which impact the image reproduction. A new tool/kit for the evaluation of ICC-profiles has been created. The goal of this educational kit is to facilitate and exemplify the practical understanding of profiles and their use for the users.
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| 5. |
- Enroth, Maria, 1960-
(författare)
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Developing tools for sustainability management in the graphic arts industry
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The main aim of this thesis is to develop and test industry-specific, applied work procedures and tools for environmental and emerging sustainability work in the graphic arts industry. This includes methods to quantify, follow-up, evaluate, manage, improve and communicate the environmental performance of activities in the graphic arts supply chain and printed products.In order to achieve the aims of the thesis, a selection of work areas were chosen as the basis for developing the industry-specific work procedures and tools. The selected work areas are the following: environmental management (being a part of sustainability management), environmental and sustainability strategies, environmental indicators and design for environment (DfE).The research presented in this thesis was based on survey research methods, case studies and multi-company studies. Within the framework of these methods, quantitative and qualitative techniques for data gathering were used. The companies included in the studies were selected according to their willingness, interest and motivation to participate and develop their environmental or sustainability work.The most significant results of the research presented in this thesis regarding the selected work areas are the following:• An evaluation of early certified environmental management systems (EMSs) in Sweden identified four areas as priorities in making the EMSs more efficient. Two of them, viz. improvement in the follow-up of environmental work, and the linking of EMSs to product design, were developed for the graphic arts industry. The remaining two areas were clarifying the identification process and assessment of environmental aspects, and streamlining and co-ordinating different management systems.• An established and successfully tested working method for formulating and realising corporate sustainability strategies in the graphic arts industry.• Industry-specific environmental indicator models for the graphic arts industry with defined methods for standardised inventorying and calculations. These models have been tested, used and approved of by the industry itself.• Collected and compiled data for the developed environmental indicator models. Data have been collected from quite a large number of companies (10-20 companies for each of the printing techniques covered, i.e. coldset offset, heatset offset and gravure) over a period of several years.• The use of the industry-specific environmental indicator models was developed and illustrated.• A described and recommended work procedure for DfE in graphic arts companies including industry-specific tools for applying DfE to printed products, in the form of a manual and a checklist. The checklist was designed so that it can serve as a simple tool for the environmental assessment of printed products. The tools were tested by graphic arts companies.
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| 6. |
- Fransson, Martin, 1978-, et al.
(författare)
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A preliminary study of modeling and simulation in individualized drug dosage – azathioprine on inflammatory bowel disease
- 2007
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Ingår i: SIMS 2006: Proceedings of the 47th Conference on Simulation and Modelling, Helsinki, Finland. - Helsinki : Kopio Niini Oy. - 9525183300 ; , s. 216-220
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Konferensbidrag (refereegranskat)abstract
- Individualized drug dosage based on population pharmacokinetic/dynamic models is an important future technology used to reduce or eliminate side effects of certain drugs, e.g. cancer drugs. In this paper we report preliminary results from work-in-progress: a simplified linear model of the metabolism of a cancer treatment drug was estimated from experimental data. The model was then validated against the same data as a test of the adequacy of the model structure. From this investigation it became apparent that the model structure could not be used due to its inability to recreate the dynamic properties of the system.
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| 7. |
- Gustafsson, Ulf, 1976-, et al.
(författare)
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Apical circumferential motion of the right and the left ventricles in healthy subjects described with speckle tracking
- 2008
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Ingår i: Journal of the American Society of Echocardiography. - : Elsevier BV. - 0894-7317 .- 1097-6795. ; 21:12, s. 1326-1330
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Tidskriftsartikel (refereegranskat)abstract
- Background The aim of this study was to determine whether right ventricular (RV) apical rotation could be of importance in RV function and compare this with left ventricular (LV) apical rotation. Methods Short-axis images at the apical level of both ventricles were simultaneously recorded in 14 healthy subjects (mean age, 62 ± 11 years). Results There was a significant difference in mean rotation between the two ventricles in the time interval between 50% of ejection and aortic valve closure (P < .05). At aortic valve closure, LV rotation was 10.9 ± 4.8° counterclockwise, and RV rotation was 1.1 ± 5.8° clockwise. The anterior and inferior parts of the right ventricle rotated in opposite directions toward the septum. The septal segments of both ventricles rotated inferiorly, thus likely reducing interventricular stress. Conclusion This study showed clear differences in apical rotation between the two ventricles. Whereas the left ventricle displayed uniform rotation, the right ventricle showed heterogeneous rotation, resulting overall in almost no rotation but in a “tightening belt” motion.
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| 8. |
- Gustafsson, Ulf, 1976-, et al.
(författare)
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Assessment of regional rotation patterns improves the understanding of the systolic and diastolic left ventricular function : an echocardiographic speckle-tracking study in healthy individuals
- 2009
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Ingår i: European Journal of Echocardiography. - : Oxford University Press (OUP). - 1525-2167 .- 1532-2114. ; :10, s. 56-61
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Tidskriftsartikel (refereegranskat)abstract
- AIM To elucidate the complexity of left ventricular motion throughout the cardiac cycle, we studied regional rotation in detail. METHODS AND RESULTS: Regional rotation in six subdivisions of the circumference at three levels was studied by using speckle-tracking echocardiography in 40 healthy subjects. At the basal level the inferoseptal segments rotated significantly more clockwise during systole than the opposing anterolateral segments. At the papillary level the inferoseptal segments differed significantly from the anterolateral segments, where the inferoseptal segments rotated clockwise and the anterolateral segments rotated counter-clockwise. The apical level showed significant difference in regional rotation only at aortic valve opening. In early systole, untwist before the main systolic twist was seen at the basal and apical levels; however, the duration of the basal untwist was much longer than that of the apical. The diastolic phases of rotation at the basal and apical levels matched the different filling phases. CONCLUSION: Large regional differences in rotation are present at the basal and papillary levels in healthy subjects. The diastolic untwist matches the phases of both the E-wave and A-wave and seems to be related with intraventricular pressure differences, indicating that untwist plays an important role in the filling of the ventricle.
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| 9. |
- Hindorf, Ulf, et al.
(författare)
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Adverse events leading to modification of therapy in a large cohort of patients with inflammatory bowel disease
- 2006
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Ingår i: Alimentary Pharmacology and Therapeutics. - : Wiley. - 0269-2813 .- 1365-2036. ; 24:2, s. 331-342
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Tidskriftsartikel (refereegranskat)abstract
- Background: Adverse events leading to discontinuation or dose reduction of thiopurine therapy occur in 9-28% of patients with inflammatory bowel disease. Aims: To evaluate the influence of thiopurine methyltransferase status and thiopurine metabolites in a large patient population for the risk of developing adverse event. Methods: Three hundred and sixty-four patients with inflammatory bowel disease and present or previous thiopurine therapy were identified from a local database. Results: The adverse event observed in 124 patients (34%) were more common in adults than children (40% vs. 15%, P < 0.001) and in low to intermediate (≤9.0 U/mL red blood cell) than normal thiopurine methyltransferase activity (P = 0.02). Myelotoxicity developed later than other types of adverse event. An increased frequency of adverse event was observed in patients with tioguanine (thioguanine) nucleotide above 400 or methylated thioinosine monophosphate above 11 450 pmol/ 8 × 108 red blood cell. A shift to mercaptopurine was successful in 48% of azathioprine-intolerant patients and in all cases of azathioprine-induced myalgia or arthralgia. Conclusions: A pre-treatment determination of thiopurine methyltransferase status might be appropriate as patients with low to intermediate thiopurine methyltransferase activity are more prone to develop an adverse event, determination of metabolite levels can be useful in the case of an adverse event. Mercaptopurine therapy should be considered in azathioprine-intolerant patients. © 2006 The Authors.
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| 10. |
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