Implementation of block device drivers in userspace of modern general-purpose operating systems, although possible, is fairly uncommon, poorly supported and usually achieves only low performance. Being able to implement high- performance drivers in userspace with ease would allow for faster iterations in storage research and would make it possible to design block devices which operate in radically different ways. In this thesis, we present Block Device in Userspace (BUSE), a Linux ker- nel module and communication protocol which makes it easy to develop userspace block-device drivers. Compared to the existing approaches, BUSE can scale on modern multicore architectures and provides at least 7x higher throughput with significantly simpler setup. Furthermore, the kernel module communicates with the userspace driver through shared memory, eliminating an extraneous memory copy. BUSE also solves the write-after-write and read- after-write consistency issues which stem from the use of multiple hardware queues in the Linux storage stack, allowing the implementation to focus on the domain of the problem. As a proof-of-concept, we implemented Block Device in S3 (BS3), a userspace block device implementation backed by Amazon S3 (or any other S3-compatible storage) on top of BUSE. BS3 can be used as a generic disk...

Detection of malicious logic on a hardware device is difficult to detect. This thesis proposes a device driver that emulates a hardware device and that device’s software driver. This device driver attacks the target system by accessing the hard disk in order to perform read and write transactions without the knowledge of the operating system or intrusion detection/prevention software. The attacks performed by the driver compromise the confidentiality, integrity, and availability of data on the target system’s disk drive. The attacks performed by the device driver have a less than one percent impact on system performance. This thesis, while tested in a Windows environment, applies to other operating systems (such as Linux/Unix, etc.) and thus has major implications for a wide range of users.

A properly conducted forensic examination is one of the most fundamental aspects of a digital investigation. Examiners are obligated to obtain the skills necessary to use forensic tools and methodologies and rely on sound judgment when analyzing a digital device. Anytime during this process, the quality of the methods, skills, and expertise of the examiner may be challenged, thus, placing the forensic value of the evidence collected during the process in jeopardy. In order to combat the potential challenges posed as a result of the forensic examination process, the digital forensics community must ensure that suitable protocols are used throughout the analysis process. Currently, there is no standard methodology forensic examiners use to analyze a digital device. Examiners have made use of a model derived from the Digital Forensic Research Workshop in 2001 and the application of ad-hoc techniques has become routine. While these approaches may reveal potential data of evidentiary value when applying them to digital devices, their core purpose specifically involves the analysis of computers. It is not clear how effective these methods have been when examining other digital technologies, in particular Small Scale Digital Devices (SSDDs). Due to these mitigating factors, it is critical to develop standard scientifically sound methodologies in the area of digital forensics that allow us to evaluate various digital technologies while considering their distinctive characteristics. This research addresses these issues by introducing the concept of an extendable forensic process model applicable to smartphones regardless of platform. The model has been developed using the property of invariance to construct a core components list which serves as the foundation of the proposed methodology. This dissertation provides a description of the forensic process, the models currently used, the developed model, and experiments to show its usefulness.

Sepsis is an uncontrolled response to infection. Severe sepsis is associated with organ dysfunction, and has mortality rate of 30-50%. Identification of severity of sepsis and prediction on mortality is crucial in making clinical decisions. Recently, cell-free DNA (cfDNA) in blood was found to have high discriminative power in predicting ICU mortality in patients with severe sepsis. In an analysis of 80 severely septic patients, the mean cfDNA level in survivors (1.16±0.13μg/ml) was similar to that of healthy volunteers (0.93±0.76μg/ml), while that of non-survivors (4.65±0.48μg/ml) was notably higher. Therefore, rapid quantification of cfDNA concentration in blood will enable physicians to quickly predict mortality of sepsis and decide on treatment. Current methods for quantification of cfDNA involve multiple steps including centrifugation, DNA-extraction from plasma, and its quantification either through spectroscopic methods or quantitative PCR. The whole process is time consuming, thus is not suitable for immediate bedside assessment. To solve the problems, a microfluidic device is designed and fabricated in this thesis, which is potential for cfDNA quantification directly using blood in 5 minutes. The goal is to use this device for distinguishing survivors or healthy donors from non-survivors in patients with severe sepsis. The two-layer device consists of a sample channel (top) and an accumulation channel (bottom) that intersect each other. The accumulation channel is preloaded with 1% agarose gel, and the blood containing cfDNA and intercalating fluorescent dye is loaded in the sample channel. Fluorescently labeled DNA is able to be trapped and concentrated at the intersection using a DC electric field, and fluorescent intensity of the accumulated DNA is representative of its concentration in the blood. The simulated electric field in the sample channel reveals that both the magnitude and the gradient of electric field reach their maximum values at the intersection. Force analysis shows that DNA was driven into the gel by the dominate electrophoretic force, while red blood cells moved away from the gel due to a strong dielectrophoretic force. In this thesis, 4 types of samples have been used to characterize the performance of the device. It showed that DNA was efficiently accumulated at the intersection, and the fluorescent intensity could be measured using a fluorescent microscope. Samples from healthy donors were able to be distinguished from that of severely septic patients in 5 minutes. However, better resolution was needed for differentiating various cfDNA concentrations in patient samples. The discussion on the effect of applied voltage showed that 9V is an optimized setting compared with 3V and 15V. In addition, it has been proved that the fluorescent reagent could be immobilized in the device and the sample preparation could be absolutely eliminated. In summary, the device proposed in this thesis is capable of distinguishing severely septic patients from healthy donors using clinical plasma in 5 minutes, and is potential to be applied in clinical blood samples. It has low cost, and is ready to be developed into a fully functioned system. This tool can be a valuable addition to the ICU to rapidly assess the severity of sepsis for informed decision making. / Thesis / Master of Applied Science (MASc)

“Reclaiming the non- places” is an ambition to activate underutilized urban spaces- normally referred to as “non- places”. Non- place is a term founded by philosopher Marc Augé, describing places characterized by anonymity, such as airports, hotels, motorways etc… Based on this information, one could find new examples of non- places in Umeå. As a student, the main campus of Umeå became an interesting site to investigate. How could I improve this site architecturally, by introducing my notion of the non- place?  When inventing a spatial programme, it felt logic to relate the function of the structure to the function of the site. Therefore, I decided the programme to be about learning.  However, I don’t want to replicate the logic of the typical learning environment, I imagine that my proposal could rethink the learning experience.  We are all aware that seminars and lectures can become boring, even if the subject itself is interesting. As human beings, we are not meant to sit still for too long. Therefore, the typical classroom is poorly designed.  My ambition is to create a free learning environment where people can learn and move at the same time. I believe that “learning by moving” could be a better tool than “learning by sitting down”. I also have a futuristic viewpoint on the project. What technologies could enhance the learning experience?  I want the learning process to be an active experience that touch all the senses.

Canine cadaveric forelimbs (136) were randomly assigned to either treatment (aiming device) or control (fluoroscopic-guided) groups, and to either diplomate or resident for humeral transcondylar screw placement. Each limb underwent a transcondylar humeral screw placement from a lateral to medial direction. Digital radiography was used to evaluate screw trajectory, measured as deviation from the epicondylar line, and eccentricity on the humeral condyle. Procedure time, difference in outcome based on experience level, and complications were recorded. In the right limb, screw trajectory with the aiming device was decreased compared to fluoroscopy. There was no difference of accuracy between leg laterality with fluoroscopy. Screw trajectory was increased with resident versus diplomate procedures. Eccentricity deviation was decreased in fluoroscopy groups. The findings of this current study suggest that the universal aiming device produced accurate transcondylar screws with comparable results to fluoroscopic- guided methods.

This is an open access article under CC BY license (https://creativecommons.org/licenses/by/4.0/) Background: Effects of internal and external workloads (IL, EL) on lower limb soft-tissue injuries (LLSTI) risk in male soccer players has been described, the relationships remain unclear in collegiate female (soccer players. Objective: The purpose was to examine the mean difference in IL and EL in LLSTI between non-injured and injured groups (N-IG and IG). Method: 20 collegiate female soccer players (age: 19.2±1.2years; height: 168.2±7.3cm; body mass: 41.0±17.9kg) were included for 14 week competitive season. IL included average heart rate (Avg-HR) and high heart rate zone. EL included total distance, average speed (Avg-Spd), and high-speed running distance. Injuries were counted if (a) they were LLSTI and muscular/ ligamentous strains or tears and tendon problems, and (b) the players missed more than one match or training session. Acute (7-day simple average) and chronic (21-day simple average) IL and EL were calculated in the IG while the mean of acute (7-day) and chronic (21-day) IL and EL were computed in the NIG. Acute Chronic Workload Ratio (ACWR) was calculated as the ratio of acute and chronic IL and EL. Results: Seven LLSTI occurred over 14 weeks. The acute Avg-HR and ACWR of Avg-Spd were significantly higher in the IG than the N-IG (p=0.001 and 0.024). IL and EL in the IG were placed below or above the mean of the N-IG. Conclusion: LLSTI might occur at high and low workloads in collegiate female soccer players. This may support the use of micro-technology to monitor workload based on individual player’s threshold to reduce LLSTI.

To meet the purpose of the study, three hypotheses were tested: First, it was predicted there was a relationship between spousal connectedness and personal and spousal ICT (information and communication technology) device usage; second, it was predicted satisfaction with personal or spousal ICT device usage were mediators of the primary relationship between spousal connectedness and ICT device usage; and third, it was expected communication moderated the relationship between spousal connectedness and personal ICT device usage. A representative sample of married adults (n=208) were sampled. Personal and spousal ICT device use, satisfaction with personal and spousal ICT device use, spousal connectedness, and communication were measured and the resulting data analyzed. Regression analyses and path analyses were performed to test the hypotheses. The first and third hypotheses were found to be significant, but the second was not. The negative relationship between personal ICT device use and spousal connectedness indicates that as ICT device use increases, connectedness decreases. Communication, however, was shown to buffer this relationship. Data indicated that the more a person recalled communicating with their spouse, the less prominent was the relationship between their personal ICT device use and spousal connectedness.

This thesis presents the design and validation of a wireless interface for a vulvar quantitative sensory testing device (v-QueST). The wireless interface works in tandem with an Android application which allows a patient to indicate when their pressure pain threshold has been reached via an on-screen button. Using the fully assembled prototype, the sampling frequency and response time of the wireless interface was validated. The results indicated that the sampling frequency was sufficient to meet the desired specifications, and the time delay between the tap of the on-screen button and the reading of the force measurement was negligible. However, inspection of the force time-series acquired from the v-QueST device through Bluetooth transmission revealed systematic error. Implementation of a new signal conditioner is recommended before using the v-QueST device for research or clinical applications to objectively measure vulvar pain sensitivity.

In this study we examined the differences of performance of various input devices on a steering task. Two paths were created, one easy and one hard, with the harder path having more turning points to navigate with one of three different input devices: mouse and keyboard, Xbox 360 controller, and a joystick. Participants were also exposed to low or high stress conditions. High stress was caused by playing loud short bursts of music over headphones worn by participants during testing. Results indicated the mouse and keyboard performed better in all cases. There was no significant difference between the Xbox controller and joystick. No differences were found in the low and high stress conditions. Differences in sex were found, even when controlling for video game experience. These findings indicate that the mouse and keyboard is the best device to use on a steering task.