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71.
Interactive information visualization systems rely on widgets to allow users to interact with the data and modify the representation. We define interactive legends as a class of controls combining the visual representation of static legends and interaction mechanisms of widgets. As interactive legends start to appear in popular websites, we categorize their designs for common data types and evaluate their effectiveness compare to standard widgets. Results suggest that 1) interactive legends can lead to faster perception of the mapping between data values and visual encodings and 2) interaction time is affected differently depending on the data type. Additionally, our study indicates superiority both in terms of perception and interaction of ordinal controls over numerical ones. Numerical techniques are mostly used in today's systems. By providing solutions to allowing users to modify ranges interactively, we believe that interactive legends make it possible to increase the use of ordinal techniques for visual exploration. 相似文献
72.
[Correction Notice: An erratum for this article was reported in Vol 3(1) of Psychological Trauma: Theory, Research, Practice, and Policy (see record 2010-26899-001). There were citation errors in the last sentence of the first column of text on page 9, and a reference was omitted from the reference list. The sentence should have read: “This result is consistent with other work that has found support for the anxious and dissociative reaction associated with trauma among Latinos and how it may relate to “ataque de nervios” (Hinton, Chong, Pollack, Barlow, & McNally, 2008; Lewis-Fernandez et al., 2002; Schechter et al., 2000; Tolin, Robinson, Gaztambide, Horowitz, & Blank, 2007).] [Correction Notice: An erratum for this article was reported in of Psychological Trauma: Theory, Research, Practice, and Policy (see record 2010-26899-001). In the original article there were citation errors in the last sentence of the first column of text on page 9, and a reference was omitted from the reference list. The sentence should have read: “This result is consistent with other work that has found support for the anxious and dissociative reaction associated with trauma among Latinos and how it may relate to “ataque de nervios” (Hinton, Chong, Pollack, Barlow, & McNally, 2008; Lewis-Fernandez et al., 2002; Schechter et al., 2000; Tolin, Robinson, Gaztambide, Horowitz, & Blank, 2007).] Research on the victimization of Latino women and the subsequent psychological impact has been limited by focusing on individual forms of victimization, primarily partner violence or sexual assault. Another deficiency includes mainly using convenience and/or geographically restricted samples, which impacts the generalizability of the results. To overcome these research limitations, the Sexual Assault Among Latinas (SALAS) study aimed to evaluate the broader scope of victimization among Latino women. The study surveyed a national sample of 2,000 Latino women using random digit dial methodology. Women were asked about various forms of victimization in childhood and adulthood including physical assaults, sexual assaults, stalking, threats, and witnessed violence, as well as psychological symptomatology including depression, anxiety, anger, and dissociation. This analysis found that victimized women were more likely to experience some form of polyvictimization and/or revictimization throughout their lives, with only 36% of victimized women experiencing one form of victimization in childhood or adulthood alone. Furthermore, multiple victimization experiences significantly increased the proportion of women who experienced psychological distress symptoms in the clinical range. For almost all evaluated symptoms, the multiple forms of victimization or varying victimization patterns significantly predicted clinical levels of psychological distress over any specific form or single incident of victimization. The results suggest that victimized Latino women experience multiple forms of victimization and that the evaluation of a broader spectrum of victimization better accounts for pathological symptomatology. Clinical implications for Latino women and future research directions are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
73.
In most watermarking systems, masking models, inherited from data compression algorithms, are used to preserve fidelity by controlling the perceived distortion resulting from adding the watermark to the original signal. So far, little attention has been paid to the consequences of using such models on a key design parameter: the robustness of the watermark to intentional attacks. The goal of this paper is to demonstrate that by considering fidelity alone, key information on the location and strength of the watermark may become available to an attacker; the latter can exploit such knowledge to build an effective mask attack. First, defining a theoretical framework in which analytical expressions for masking and watermarking are laid, a relation between the decrease of the detection statistic and the introduced perceptual distortion is found for the mask attack. The latter is compared to the Wiener filter attack. Then, considering masking models widely used in watermarking, experiments on both simulated and real data (audio and images) demonstrate how knowledge on the mask enables to greatly reduce the detection statistic, even for small perceptual distortion costs. The critical tradeoff between robustness and distortion is further discussed, and conclusions on the use of masking models in watermarking drawn. 相似文献
74.
Muscle fibre types play an important role in bovine meat tenderness, and conditions the speed of ageing. Two generations of myotubes appear during foetal life. Their differentiation results in several types of fibres differing in their contractile and metabolic properties, namely type I fibres and type II fibres (IIA and IIB). Fibre types were identified using antibodies by immunohistochemistry and western-blotting techniques. The aim was to test different antibodies on foetal and adult muscles by these two techniques. Ten monoclonal antibodies reported to be specific to different myosin heavy chain (MHC) isoforms in other species were tested. Only three antibodies were selected: BF.35, specific for I and IIa MHCs, F1.652 specific for foetal MHC and SC.71 an anti II MHCs (IIa and IIb) antibody. The use of these antibodies will enable a more precise characterisation of muscle fibres and will have applications in the study of bovine muscle ontogenesis. 相似文献
75.
A simple, rigorous electromagnetic formula is derived for predicting the electromagnetic power provided by sources located in transparent or dissipative planar microcavities. With this simple approach, we compare numerically and experimentally the electromagnetic power that escapes the microcavity when the source is located in a metallodielectric or in an all-dielectric resonant planar structure. Although a strong light-extraction coefficient might be expected for metallodielectric microcavities, we show that these attractive structures suffer from metal absorption even when thin metallic layers are used. Experiments implemented with europium chelates located in metallodielectric or in all-dielectric microcavities confirm this result. 相似文献
76.
V Picard F Renaudie C Porcher MW Hentze B Grandchamp C Beaumont 《Canadian Metallurgical Quarterly》1996,87(5):2057-2064
To test the hypothesis that variations in H- and L-subunit composition in the ferritin shell affect intracellular iron metabolism, we established stable transfectants of mouse erythroleukemia cells overexpressing the H-ferritin subunit. Analyses were performed on individual clones of transfected cells induced to differentiate with hexamethylenbisacetamide (HMBA). The results showed that there was a reduction in the amount of hemoglobin produced, in inverse relationship with the level of H-subunit overexpression. Incorporation of [2-14C]glycine into heme was reduced by 20% t0 30% in the clones overexpressing H-ferritin subunit compared with control clone. However, the reduction in hemoglobin production was not reversed by addition of heme precursors (delta-aminolevulinic acid or iron) or by hemin itself. A reduced accumulation of beta-globin mRNA was also observed, which could account for the impaired hemoglobin synthesis. Furthermore, synthesis of the endogenous L-ferritin subunit was greatly repressed. Gel retardation assays performed on cytoplasmic extracts of transfected cells using an iron-responsive element (IRE) as a probe revealed that in overexpressing cells, the iron-regulatory protein (IRP) had a conformation with a high RNA-binding affinity, thus leading to translational repression of the endogenous L-ferritin synthesis. These data suggest that an increased formation of H-rich isoferritins leads to a rapid chelation of the regulatory iron pool. While the mechanism underlying the reduction in beta-globin mRNA remains to be elucidated, this study provides direct evidence for the role of IRP-mediated regulation of ferritin expression in erythroid cell metabolism. 相似文献
77.
Classement des porteurs de charge et conductivite du compose K8Na4Sb12O36 de structure KSbO3 cubique
H. Watelet J.-P. Picard G. Baud J.-P. Besse R. Chevalier 《Materials Research Bulletin》1981,16(7):877-882
Two structures have been reported for cubic KSbO3 type. One has space group Pn3, where K+ ions are in an ordered state. The other has Im3 with K+ ions in a disordered state. These ions are weakly bound in large tunnels along 〈111〉 and are mobile along them three-dimensionally.The presence of two alkaline cations in these tunnels is in favour of the ordered state. Single-crystals of K8Na4Sb12O36 are obtained and crystallize in the space group Pn3, . Using 563 independent reflections, the structure has been refined by full-matrix least squares, to factor R = 0,059.The comparison of the ionic conductivity of ordered (Pn3) and disordered (Im3) compounds is studied by the authors. 相似文献
78.
We measure with a gated intensified CCD camera the cross-polarized backscattered light from a linearly polarized laser beam penetrating a cloud made of spherical particles. In accordance with previously published results we observe a clear azimuthal pattern in the recorded images. We show that the pattern is symmetrical, that it originates from second-order scattering, and that higher-order scattering causes blurring that increases with optical depth. We also find that the contrast in the symmetrical features can be related to measurement of the optical depth. Moreover, when the blurring contributions are identified and subtracted, the resulting pattern provides a pure second-order scattering measurement that can be used for retrieval of droplet size. 相似文献
79.
Human exposure to electromagnetic fields emitted by mobile phones is characterised by the Specific Absorption Rate (sar). This value corresponds to therf power absorbed by unitary mass of the equivalent tissue. It represents the basic restriction used to define limit of human exposure torf electromagnetic fields. Academic and industrial labs have contributed through thecomobio project to define international standards for mobile phones certification. 相似文献
80.
Glidle A Yasukawa T Hadyoon CS Anicet N Matsue T Nomura M Cooper JM 《Analytical chemistry》2003,75(11):2559-2570
We describe a method, based on X-ray photoelectron spectroscopy (XPS) measurements, to assess the extent of protein adsorption or binding on a variety of different muTAS and biosensor interfaces. Underpinning this method is the labeling of protein molecules with either iodine- or bromine-containing motifs by using protocols previously developed for radiotracer studies. Using this method, we have examined the adsorption and binding properties of a variety of modified electrodeposited polymer interfaces as well as other materials used in muTAS device fabrication. Using polymer interfaces modified with poly(propylene glycol) (PPG) chains, our results indicate that a chain of at least approximately 30 monomer units is required to inhibit nonspecific adsorption from concentrated protein solutions. The XPS methodology was also used to probe specific binding of avidins and enzyme conjugates thereof to biotinylated and mixed biotin/PPG-modified polymer interfaces. In one example, using competitive binding, it was established that the mode of binding of a peroxidase-streptavidin conjugate to a biotinylated modified polymer interface was primarily via the streptavidin moiety (as opposed to nonspecific binding via the enzyme conjugate). XPS evaluation of nonspecific and specific peroxidase-streptavidin immobilization on various functionalized polymers has guided the design and fabrication of functionalized interdigitated electrodes in a biosensing muTAS device. Subsequent characterization of this device using scanning electrochemical microscopy (SECM) corroborated the adsorption and binding previously inferred from XPS measurements on macroscale electrodes. 相似文献