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Trondheim, Norway

Norwegian University of Science and Technology is a public research university located in the city of Trondheim, Norway. NTNU is the second largest of the eight universities in Norway, and, as its name suggests, has the main national responsibility for higher education in engineering and technology. In addition to engineering and the natural and physical science, the university offers advanced degrees in other academic disciplines ranging from the social science, the arts, medicine, architecture and fine art.The current rector is professor dr.med. Gunnar Bovim. Wikipedia.

Mai X.-M.,Norwegian University of Science and Technology
American Journal of Epidemiology | Year: 2012

Experimental studies suggest that vitamin D modulates the activity of adipocytes. The authors examined baseline serum 25-hydroxyvitamin D (25(OH)D) level in relation to prevalent and cumulative incident obesity in Norway. A cohort of 25,616 adults aged 19-55 years participated in both the second and third surveys of the Nord-Trøndelag Health Study (HUNT 2 (1995-1997) and HUNT 3 (2006-2008)). Serum 25(OH)D levels measured at baseline and anthropometric measurements taken at both baseline and follow-up were available for a random sample of 2,460 subjects. Overall, 40% of the 2,460 subjects had a serum 25(OH)D level less than 50.0 nmol/L, and 37% had a level of 50.0-74.9 nmol/L. The prevalence and cumulative incidence of obesity, defined as body mass index (weight (kg)/height (m) 2) ≥30, were 12% and 15%, respectively. Lower serum 25(OH)D level was associated with a higher prevalence of obesity. In the 2,165 subjects with baseline BMI less than 30, a serum 25(OH)D level less than 50.0 nmol/L was associated with a significantly increased odds ratio for incident obesity during follow-up (adjusted odds ratio = 1.73, 95% confidence interval: 1.24, 2.41). When prevalent and incident obesity were classified according to waist circumference (≥88 cm for women, ≥102 cm for men), similar results were obtained. In addition to prevalent obesity, a serum 25(OH)D level less than 50.0 nmol/L was significantly associated with new-onset obesity in adults. American Journal of Epidemiology © The Author 2012. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved.

Aamo O.M.,Norwegian University of Science and Technology
IEEE Transactions on Automatic Control | Year: 2013

Many interesting problems in the oil and gas industry face the challenge of responding to disturbances from afar. Typically, the disturbance occurs at the inlet of a pipeline or the bottom of an oil well, while sensing and actuation equipment is installed at the outlet, only, kilometers away from the disturbance. The present paper develops an output feedback control law for such cases, based on modelling the transport phenomenon as a 2 x 2 linear partial differential equation (PDE) of hyperbolic type and the disturbance as a finite-dimensional linear system affecting the left boundary of the PDE. Sensing and actuation are co-located at the right boundary of the PDE. The design provides a separation principle, allowing a disturbance attenuating full-state feedback control law to be combined with an observer. The results are applied to a relevant problem from the oil and gas industry and demonstrated in simulations. © 2012 IEEE.

Representing an environment globally, in a coarse way, and locally, in a fine-grained way, are two fundamental aspects of how our brain interprets the world that surrounds us. The neural correlates of these representations have not been explicated in humans. In this study we used fMRI to investigate these correlates and to explore a possible functional segregation in the hippocampus and parietal cortex. We hypothesized that processing a coarse, global environmental representation engages anterior parts of these regions, whereas processing fine-grained, local environmental information engages posterior parts. Participants learned a virtual environment and then had to find their way during fMRI. After scanning, we assessed strategies used and representations stored. Activation in the hippocampal head (anterior) was related to the multiple distance and global direction judgments and to the use of a coarse, global environmental representation during navigation. Activation in the hippocampal tail (posterior) was related to both local and global direction judgments and to using strategies like number of turns. A structural shape analysis showed that the use of a coarse, global environmental representation was related to larger right hippocampal head volume and smaller right hippocampal tail volume. In the inferior parietal cortex, a similar functional segregation was observed, with global routes represented anteriorly and fine-grained route information such as number of turns represented posteriorly. In conclusion, moving from the anterior to the posterior hippocampus and inferior parietal cortex reflects a shift from processing coarse global environmental representations to processing fine-grained, local environmental representations.

Giannakos M.N.,Norwegian University of Science and Technology
Computers and Education | Year: 2013

Educational games have enhanced the value of instruction procedures in institutions and business organizations. Factors that increase students' adoption of learning games have been widely studied in past; however, the effect of these factors on learners' performance is yet to be explored. In this study, factors of Enjoyment, Happiness, and Intention to Use were chosen as important attitudes in learning educational games and increasing learning performance. A two-step between group experiment was conducted: the first study compared game-based learning and traditional instruction in order to verify the value of the game. 41 Gymnasium (middle school) students were involved, and the control and experimental groups were formed based on a pretest method. The second study, involving 46 Gymnasium students, empirically evaluates whether and how certain attitudinal factors affect learners' performance. The results of the two-part experiment showed that a) the game demonstrated good performance (as compared to traditional instruction) concerning the gain of knowledge, b) learners' enjoyment of the game has a significant relation with their performance, and c) learners' intention to use and happiness with the game do not have any relation with their performance. Our results suggest that there are attitudinal factors affecting knowledge acquisition gained by a game. © 2013 Elsevier Ltd. All rights reserved..

Zhang S.J.,Norwegian University of Science and Technology
Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Year: 2014

The mammalian space circuit is known to contain several functionally specialized cell types, such as place cells in the hippocampus and grid cells, head-direction cells and border cells in the medial entorhinal cortex (MEC). The interaction between the entorhinal and hippocampal spatial representations is poorly understood, however. We have developed an optogenetic strategy to identify functionally defined cell types in the MEC that project directly to the hippocampus. By expressing channelrhodopsin-2 (ChR2) selectively in the hippocampus-projecting subset of entorhinal projection neurons, we were able to use light-evoked discharge as an instrument to determine whether specific entorhinal cell groups--such as grid cells, border cells and head-direction cells--have direct hippocampal projections. Photoinduced firing was observed at fixed minimal latencies in all functional cell categories, with grid cells as the most abundant hippocampus-projecting spatial cell type. We discuss how photoexcitation experiments can be used to distinguish the subset of hippocampus-projecting entorhinal neurons from neurons that are activated indirectly through the network. The functional breadth of entorhinal input implied by this analysis opens up the potential for rich dynamic interactions between place cells in the hippocampus and different functional cell types in the entorhinal cortex (EC).

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