This study describes the development and testing of a virtual reality locomotion system that uses the user’s arm swings as input. This system has also been integrated with audio and haptic feedback that reacts to the user’s velocity and the surface they’re currently walking on, in an attempt to provide an intuitive and immersive VR locomotion experience. To achieve this, an open source ArmSwinger implementation has been adapted, and custom haptic belts were crafted to display haptic feedback around the user’s feet. Tests with three participants have shown that the system is able to be operated even by users unfamiliar with VR, and the addition of locomotion feedback mostly succeeds in improving the user experience, albeit some issues with synchronization were brought up. / Denna studie beskriver utvecklingen och testningen av ett virtuell verklighet lokomotivsystem som använder användarens armsvängningar som ingång. Detta system har också integrerats med ljud och haptisk feedback som reagerar på användarens hastighet och ytan de för närvarande går på, i ett försök att ge en intuitiv och uppslukande VV rörelseupplevelse. För att uppnå detta har en öppen källkod ArmSwinger implementering anpassats och anpassade haptiska bälten har utformats för att visa haptisk feedback runt användarens fötter. Test med tre deltagare har visat att systemet kan drivas även av användare som inte känner till VV, och tillägget av rörelseåterkoppling lyckas främst förbättra användarupplevelsen, även om vissa problem med synkronisering togs upp.

This experiment determined the effects of transplantation of fetal hippocampus on the ability of male rats with hippocampal lesions to acquire versions of a radial arm maze that depended on either extramaze cues or intramaze cues for solution. Rats receiving transplants took significantly more trials than control rats to emit three consecutive errorless trials in the extramaze cue (spatial) variation of the maze. Rats with just hippocampal lesions never differed from any other group. No differences in this measure were found for the intramaze cue condition. Rats receiving transplants made more repeat entries into reinforced arms in both versions of the maze than control rats and more reentries into neverbaited arms in the spatial maze. Rats with hippocampal lesions failed to differ from any other group on this measure in the spatial maze, but were different from normal rats in the intramaze cue maze. These data suggest that in some tasks transplants of fetal tissue lead to greater behavioral impairment than lesions alone.

No description available.

Debate continues on the merits of strictly limiting alcohol consumption during all of pregnancy, and whether “safe” consumption levels and/or times exist. Only a relatively few experimental studies have been conducted that limit the timing of exposure to specific events during development and the exposure level to one that might model sporadic, incidental drinking during pregnancy. In the present study, the effects of two acute gavage exposures to low and moderate levels of ethanol (peak blood ethanol concentrations (BEC) of 104 and 177 mg/dl, respectively) either during gastrulation on gestational day (GD) 7 (at GD7:0 h and GD7:4 h) or during neurulation on GD8 (at GD8:6 h and GD8:10 h) on the spatial learning and memory abilities of adult mice in the radial arm maze (RAM) were examined. Mice were selected from a prenatal ethanol exposure (PAE) cohort that had been tested as neonates for their sensorimotor development (Schambra et al., 2015) and as juveniles and young adults for open field activity levels and emotionality (Schambra et al., 2016). Mice exposed on either of the two gestational days to acute, low or moderate levels of ethanol were deficient in overall performance in the RAM in adulthood. Importantly, mice in ethanol exposed groups took longer to reach criterion in the RAM, and many mice in these groups failed to do so after 48 trials when testing was terminated. Exposure to a low level of ethanol on either GD7 or GD8, or a moderate level on GD7, resulted in significant impairment in spatial reference (long-term) memory, while only mice exposed on GD7 to the low level of ethanol were significantly impaired in spatial working (short-term) memory. Mice exposed to the low ethanol level on either day had significantly shorter response latencies, which may reflect impairment of processes related to response inhibition or executive attention in these mice. For all measures, distributions of individual scores revealed a relatively small subset of mice in each PAE group who scored well outside the range of the control group, which skewed the population distributions to varying degrees in the direction of worse performance for the PAE groups. Overall the data suggest that after acute, low level ethanol exposure early in gestation, the likelihood that an individual mouse embryo experienced measureable ill-effects due to the exposure was rather low, but in a few of the embryos, damage occurred that resulted in significant deficits in later performance. The overall characteristics of our cohort of PAE mice, including delayed sensorimotor development, mild hypoactivity and increased emotionality, as shown in previous studies, together with deficits in spatial learning and memory as shown here, resemble those in a subset of human Fetal Alcohol Spectrum Disorder (FASD) diagnoses, specifically ADHD-Inattentive type (ADHD-I) and/or Sluggish Cognitive Tempo (SCT). Although possible correspondences between mechanisms underlying PAE-induced deficits in mice and those operating in humans remain undefined, further study with this mouse PAE model may ultimately help advance understanding of the causes of these conditions in affected children. This study highlights the possibility of risk associated with low to moderate sporadic alcohol consumption during the first month of human pregnancy.

There are millions of fall-related injuries worldwide requiring medical attention on a yearly basis. These falls place a financial burden on the healthcare system. These falls can occur in the event of disruption in the postural control system and/or a loss of balance while walking. Previously, most gait studies have focused on the assessment of the lower extremities while neglecting the contribution of arm swing as it was believed to be a passive motion. However, it has been shown that there is an active component to arm swing. Moreover, these arm movements have been shown to affect the motion of the center of mass when walking. Therefore, arm swing could mitigate the destabilizing effects of perturbations caused by challenging surfaces. Additionally, no studies have examined the effect of arm swing when walking on a rocky surface. This type of surface causes perturbations in the anteroposterior and mediolateral directions simultaneously, leading to uneven center of mass displacement and spatiotemporal modifications. Hence, the present study assessed the effect of normal arm swing, held arm swing and active arm swing on postural control and dynamic stability when walking on regular and rocky surface. We hypothesized that active arm swing will have a negative impact on postural control and gait dynamics on a regular surface, while rocky surface walking will decrease stability and increase spatiotemporal variability. Additionally, we expect active arm swing to attenuate the negative effects of the rocky surface. Fifteen healthy young adults from the University of Ottawa community (mean age 23.4 ± 2.8 years) were recruited to participate in this study. They were asked to walk using three different arm conditions (normal, held and active arm swing) on the dual-belt CAREN-Extended System (Motek Medical, Amsterdam, NL) on simulated regular and rocky surface. This last is generated using the “Rumble” module (maximum range of ±2 cm at 0.6 Hz vertically, ±1° at 1 Hz pitch, and ±1° at 1.2 Hz roll). Mean, standard deviation and maximal values of trunk linear and angular velocity were calculated in all three planes. Moreover, step length, time and width mean and coefficient of variation as well as margin of stability mean and standard deviation were calculated. A mixed linear model was performed to compare the effects of the arm swing motions and surface types. The arm and surface conditions were set as fixed effects, while the walking speed was set as a covariate. Active arm swing increased trunk linear and angular velocity variability and peak values compared to normal and held arm conditions. Active arm swing also increased participants’ step length and step time, as well as the variability of margin of stability. Similarly, rocky surface walking increased trunk kinematics variability and peak values compared to regular surface walking. Furthermore, rocky surface increased the average step width while reducing the average step time. The spatiotemporal adaptations show the use of “cautious” gait to mitigate the destabilizing effects of both the active arm swing and rocky surface walking and, ultimately, maintain stability.

Thirteen bacterial cultures were isolated from the North arm of Great Salt Lake during the months of January and February of 1973. Eleven isolates were gram-negative pleomorphic rods which lysed in hypotonic solution. The remaining two were gram-positive cocci. All isolates and one known strain of Halobacterium salinarium were subjected to examination of morphological, cultural, physiological, and biochemical characteristics. A numerical taxonomic analysis was applied to the compiled characters to compute a coefficient of similarity for each individual isolate as compared to all other isolates. A comparative analysis was included in the similarity computation using characters assembled from those reported in the literature for six taxonomically accepted species of halophilic bacteria. The lake isolates proved to be extreme halophiles with relative high levels of similarity between each other and the known bacteria included in the numerical analysis.

No description available.

This report describes a project aimed at determining the angle of the landing platform to the drones using a tilted platform, IMU, and image processing algorithms. The goal of this project is to determine the safe landing of drones and drone landings by optimizing the landing location via platform tilt adjustment and angle computation. A robotic arm was used to tilt the rectangular platform, and a web camera was used to get images from the top view. Image processing methods built-in MATLAB allow for approximate landing angle determination and angle determination is also done with IMU. The findings confirm the system’s efficiency, with reasonable angle estimates and successful drone landings.

This thesis project investigated whether or not the use of an embedded system could help blackjack players to improve their game. This was done by designing and building a robot, that plays blackjack according to a card counting strategy. A robot prototype was built successfully, using a USB-camera to detect the cards and servo-motors to signal its playing decisions via hand gestures. Tests showed that the robot has a 1.4% edge over the house on average. However, due to high variance in the outcomes, the positive return found is non-significant. Recommendations of future work is proposed, including how both players and casinos can benefit from this project. / Detta examensarbete undersökte om ett inbyggt system kan hjälpa blackjackspelare att förbättra sitt spel. Detta gjordes genom att konstruera och bygga en robot, som spelar blackjack enligt en korträkningsstrategi. En robotprototyp byggdes med hjälp av en USB-kamera för att läsa av spelkorten, och servomotorer för att signalera spelbeslut genom handgester. Tester visade att roboten har i genomsnitt 1.4% fördel över huset. Dock är denna positiva avkastning icke-signifikant på grund av hög varians i utfallen. Rekommendationer om framtida arbete föreslås, som inkluderar hur både spelare och casinon kan dra nytta av detta projekt.

Recycling is becoming more crucial due to the fast pace of consumerism. This thesis explores how well a robot arm, with three degrees of freedom, can be implemented to give an autonomous recycling process. After the prototyping phase it was found that a cylindrical robot arm was best suited for the project. Computer vision in addition with machine learning is used for sorting and detecting objects. The end effector is a suction cup, connected to a plastic 60-milliliter syringe. Negative pressure is created by pulling and pushing a lead screw connected to a stepper motor. The accuracy of the ML-model, the robot’s movement andmax weight are evaluated. The ML-model is trained to detect four classes; plastic, metal, paper, and glass. The thesis found that the ML-model could classify plastic the most sufficient and paper the least. The robot arm’s movement had an average error of 0.54 cm and the maximum weight was 900 grams. For future development it would be interesting to compare a range of different suction cups, to see how the material, diameter, and depth would affect its ability to pick up various objects. Additionally, the model could be enhanced by training it on a larger dataset.