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71.
Functional stability limits (FSLs) are the percentage of the base of support that individuals are willing to extend their centre of pressure. The objective of this study was to provide construct validation of FSLs as a measure of balance by comparing FSLs across ages and with clinical balance measures. A total of 52 participants volunteered. FSLs significantly decreased with age (p < 0.004). Correlations between FSLs and age (-0.56 < R < -0.73), multi-directional reach test (0.35 < R < 0.75) and anteroposterior and mediolateral centre of pressure excursions during static stance (-0.29 < R < -0.72) were generally moderate to good. Cronbach's alpha (0.75) indicated that these measures were internally consistent, i.e. measuring similar aspects of the balance construct. FSLs appear to be valid indicators of balance ability. They may be used in posture prediction models to determine when a step is required when reaching or lifting objects and in biomechanical models as a means of incorporating stability constraints. 相似文献
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Interactive visualization of intercluster galaxy structures in the horologium-reticulum supercluster
Miller J Quammen CW Fleenor MC 《IEEE transactions on visualization and computer graphics》2006,12(5):1149-1155
We present GyVe, an interactive visualization tool for understanding structure in sparse three-dimensional (3D) point data. The scientific goal driving the tool's development is to determine the presence of filaments and voids as defined by inferred 3D galaxy positions within the Horologium-Reticulum supercluster (HRS). GyVe provides visualization techniques tailored to examine structures defined by the intercluster galaxies. Specific techniques include: interactive user control to move between a global overview and local viewpoints, labelled axes and curved drop lines to indicate positions in the astronomical RA-DEC-cz coordinate system, torsional rocking and stereo to enhance 3D perception, and geometrically distinct glyphs to show potential correlation between intercluster galaxies and known clusters. We discuss the rationale for each design decision and review the success of the techniques in accomplishing the scientific goals. In practice, GyVe has been useful for gaining intuition about structures that were difficult to perceive with 2D projection techniques alone. For example, during their initial session with GyVe, our collaborators quickly confirmed scientific conclusions regarding the large-scale structure of the HRS previously obtained over months of study with 2D projections and statistical techniques. Further use of GyVe revealed the spherical shape of voids and showed that a presumed filament was actually two disconnected structures. 相似文献
74.
Claudio Luparello Ilenia Cruciata Andreas C. Joerger Cory A. Ocasio Rhiannon Jones Raysa Khan Tareque Mark C. Bagley John Spencer Martin Walker Carol Austin Tiziana Ferrara Pietro DOca Rossella Bellina Rossella Branni Fabio Caradonna 《International journal of molecular sciences》2021,22(7)
The carbazole compounds PK9320 (1-(9-ethyl-7-(furan-2-yl)-9H-carbazol-3-yl)-N-methylmethanamine) and PK9323 (1-(9-ethyl-7-(thiazol-4-yl)-9H-carbazol-3-yl)-N-methylmethanamine), second-generation analogues of PK083 (1-(9-ethyl-9H-carbazol-3-yl)-N-methylmethanamine), restore p53 signaling in Y220C p53-mutated cancer cells by binding to a mutation-induced surface crevice and acting as molecular chaperones. In the present paper, these three molecules have been tested for mutant p53-independent genotoxic and epigenomic effects on wild-type p53 MCF-7 breast adenocarcinoma cells, employing a combination of Western blot for phospho-γH2AX histone, Comet assay and methylation-sensitive arbitrarily primed PCR to analyze their intrinsic DNA damage-inducing and DNA methylation-changing abilities. We demonstrate that small modifications in the substitution patterns of carbazoles can have profound effects on their intrinsic genotoxic and epigenetic properties, with PK9320 and PK9323 being eligible candidates as “anticancer compounds” and “anticancer epi-compounds” and PK083 a “damage-corrective” compound on human breast adenocarcinoma cells. Such different properties may be exploited for their use as anticancer agents and chemical probes. 相似文献
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Anderson Deborah K.; Lord Catherine; Risi Susan; DiLavore Pamela S.; Shulman Cory; Thurm Audrey; Welch Kathleen; Pickles Andrew 《Canadian Metallurgical Quarterly》2007,75(4):594
Verbal skills were assessed at approximately ages 2, 3, 5, and 9 years for 206 children with a clinical diagnosis of autism (n = 98), pervasive developmental disorders-not otherwise specified (PDD-NOS; n = 58), or nonspectrum developmental disabilities (n = 50). Growth curve analyses were used to analyze verbal skills trajectories over time. Nonverbal IQ and joint attention emerged as strong positive predictors of verbal outcome. The gap between the autism and other 2 groups widened with time as the latter improved at a higher rate. However, there was considerable variability within diagnostic groups. Children with autism most at risk for more serious language impairments later in life can be identified with considerable accuracy at a very young age, while improvement can range from minimal to dramatic. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
For broadband packet networks to be widely useful to society, they must dynamically recognize some network flows, like those that deal with disaster response, military operations, or emergencies as having greater importance than others. This paper proposes an architecture of geographically distributed ticket servers that issue importance tickets that indicate the priority that a flow should be given in the current dynamic network context. Any type of user or flow can be given priority, depending on the user needs and the context. User agents contact ticket servers using an agent communication language; then a ticket server intelligent agent determines how valuable of a ticket to issue. Use of ticket servers and agent communication enables quick adaptation to dynamic context changes and provides user feedback so that high priority communication activities can be conducted effectively. 相似文献
79.
Michael K. Henry Alexey V. Gorshkov Yaakov S. Weinstein Paola Cappellaro Joseph Emerson Nicolas Boulant Jonathan S. Hodges Chandrasekhar Ramanathan Timothy F. Havel Rudy Martinez David G. Cory 《Quantum Information Processing》2007,6(6):431-444
Incoherent noise is manifest in measurements of expectation values when the underlying ensemble evolves under a classical
distribution of unitary processes. While many incoherent processes appear decoherent, there are important differences. The
distribution functions underlying incoherent processes are either static or slowly varying with respect to control operations
and so the errors introduced by these distributions are refocusable. The observation and control of incoherence in small Hilbert
spaces is well known. Here we explore incoherence during an entangling operation, such as is relevant in quantum information
processing. As expected, it is more difficult to separate incoherence and decoherence over such processes. However, by studying
the fidelity decay under a cyclic entangling map we are able to identify distinctive experimental signatures of incoherence.
This is demonstrated both through numerical simulations and experimentally in a three qubit nuclear magnetic resonance implementation.
相似文献
80.
Selective toxicity of zinc oxide nanoparticles to prokaryotic and eukaryotic systems 总被引:1,自引:0,他引:1
Reddy KM Feris K Bell J Wingett DG Hanley C Punnoose A 《Applied physics letters》2007,90(213902):2139021-2139023
We report on the toxicity of ZnO nanoparticles (NPs) to gram-negative and gram-positive bacterial systems, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and primary human immune cells. ZnO NP (~13 nm) showed complete inhibition of E. coli growth at concentrations 3.4 mM, whereas growth of S. aureus was completely inhibited for 1 mM. Parallel experiments using flow cytometry based assays clearly demonstrated that growth inhibitory properties of ZnO NP were accompanied by a corresponding loss of cell viability. Identical ZnO NP had minimal effects on primary human T cell viability at concentrations toxic to both gram-negative and gram-positive bacteria. Collectively, these experiments demonstrate selectivity in the toxic nature of ZnO NP to different bacterial systems and human T lymphocytes. Developing selective toxicity to biological systems and controlling it by NP design could lead to biomedical and antibacterial applications. 相似文献