6,303 research outputs found
Aneuploidy and proteotoxic stress in cancer
Although nearly ubiquitous in cancer, aneuploidy exerts detrimental effects on human cells. We recently demonstrated that aneuploid human cells exhibit impaired heat shock factor protein 1 (HSF1) and HSP90 function, suggesting a functional link between two recurring features of cancer cells: aneuploidy and proteotoxic stress. Further, our fi ndings implicate HSF1 as a key factor in mitigating the effects of aneuploid
Turning Point Scotland's Housing First Project Evaluation: Final Report
GIS maps are one kind of complex display in which people search for targets. Recent studies have shown that the choice of colour-scales when displaying these maps has important implications for people's strategies in searching these displays (Donnelly, Cave, Welland & Menneer, 2006). The current study follows up on this research. Observers searched for multiple targets in each display. Two targets were red and two were blue, and targets were not very salient. Observers searched until all targets were found. This often took several seconds and many fixations. The order in hich observers found targets suggested that they were more reliant on search for particular colours under some color-scales than under others. What will be presented here is a number of oculomotor measures used to explore how search was guided in the displays: the degree to which fixations clustered around targets, the image characteristics of regions of the display that were fixated, and goodness of fit to fixation distributions of Itti & Koch saliency maps, where the features used to compute saliency were varied. The goal was to see which measures would best pick up on differences in what guided search through complex display
Single vortex states in a confined Bose-Einstein condensate
It has been demonstrated experimentally that non-axially symmetric vortices
precess around the centre of a Bose-Einstein condensate. Two types of single
vortex states have been observed, usually referred to as the S-vortex and the
U-vortex. We study theoretically the single vortex excitations in spherical and
elongated condensates as a function of the interaction strength. We solve
numerically the Gross-Pitaevskii equation and calculate the angular momentum as
a function of precession frequency. The existence of two types of vortices
means that we have two different precession frequencies for each angular
momentum value. As the interaction strength increases the vortex lines bend and
the precession frequencies shift to lower values. We establish that for given
angular momentum the S-vortex has higher energy than the U-vortex in a rotating
elongated condensate. We show that the S-vortex is related to the solitonic
vortex which is a nonlinear excitation in the nonrotating system. For small
interaction strengths the S-vortex is related to the dark soliton. In the
dilute limit a lowest Landau level calculation provides an analytic description
of these vortex modes in terms of the harmonic oscillator states
Integration of Modelling and Monitoring to Optimize Network Control: Two Case Studies from Lisbon
AbstractIn recent years, EPAL, Portugal's largest water supply company, has successfully implemented projects for optimizing control of the Lisbon distribution network, which include the implementation of a network monitoring project (WONE) aimed at reducing water losses, as well as the development of an EPANET based all-pipe hydraulic network model. Building on the individual success of each of these projects, the integration of these two base tools has proved to be extremely useful as regards managing situations of great complexity, as demonstrated in the two case studies that are presented in this paper
Avoided intersections of nodal lines
We consider real eigen-functions of the Schr\"odinger operator in 2-d. The
nodal lines of separable systems form a regular grid, and the number of nodal
crossings equals the number of nodal domains. In contrast, for wave functions
of non integrable systems nodal intersections are rare, and for random waves,
the expected number of intersections in any finite area vanishes. However,
nodal lines display characteristic avoided crossings which we study in the
present work. We define a measure for the avoidance range and compute its
distribution for the random waves ensemble. We show that the avoidance range
distribution of wave functions of chaotic systems follow the expected random
wave distributions, whereas for wave functions of classically integrable but
quantum non-separable wave functions, the distribution is quite different.
Thus, the study of the avoidance distribution provides more support to the
conjecture that nodal structures of chaotic systems are reproduced by the
predictions of the random waves ensemble.Comment: 12 pages, 4 figure
Effect of cochlear implant electrode insertion on middle-ear function as measured by intra-operative laser Doppler vibrometry
Hypothesis: The aim of this study was to investigate the impact of cochlear implant electrode insertion on middle-ear low frequency function in humans.Background: Preservation of residual low frequency hearing with addition of electrical speech processing can improve the speech perception abilities and hearing in noise of cochlear implant users. Preservation of low frequency hearing requires an intact middle-ear conductive mechanism in addition to intact inner-ear mechanisms. Little is known about the effect of a cochlear implant electrode on middle-ear function.Methods: Stapes displacement was measured in seven patients undergoing cochlear implantation. Measurements were carried out intra-operatively before and after electrode insertion. Each patient acted as his or her own control. Sound was delivered into the external auditory canal via a speaker and calibrated via a probe microphone. The speaker and probe microphone were integrated into an individually custom-made ear mould. Ossicular displacement in response to a multisine stimulus at 80 dB SPL was measured at the incudostapedial joint via the posterior tympanotomy, using an operating microscope mounted laser Doppler vibrometry system.Results: Insertion of a cochlear implant electrode into the scala tympani had a variable effect on stapes displacement. In three patients, there was little change in stapes displacement following electrode insertion. In two patients, there was a significant increase, while in a further two there was a significant reduction in stapes displacement. This variability may reflect alteration of cochlear impedance, possibly due to differing loss of perilymph associated with the electrode insertion.Conclusion: Insertion of a cochlear implant electrode produces a change in stapes displacement at low frequencies, which may have an effect on residual low frequency hearing thresholds
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