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1.
Gamut mapping deals with the need to adjust a color image to fit into the constrained color gamut of a given rendering medium. A typical use for this tool is the reproduction of a color image prior to its printing, such that it exploits best the given printer/medium color gamut, namely the colors the printer can produce on the given medium. Most of the classical gamut mapping methods involve a pixel-by-pixel mapping and ignore the spatial color configuration. Recently proposed spatial-dependent approaches for gamut mapping are either based on heuristic assumptions or involve a high computational cost. In this paper, we present a new variational approach for space-dependent gamut mapping. Our treatment starts with the presentation of a new measure for the problem, closely related to a recent measure proposed for Retinex. We also link our method to recent measures that attempt to couple spectral and spatial perceptual measures. It is shown that the gamut mapping problem leads to a quadratic programming formulation, guaranteed to have a unique solution if the gamut of the target device is convex. An efficient numerical solution is proposed with promising results.  相似文献   
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Carbon Black (CB)-containing immiscible polymer blends based on high-impact polystyrene/thermoplastic polyurethane (HIPS/TPU) were studied as sensing materials for an homologous series of alcohols, including, methanol, ethanol and 1-propanol. The studied immiscible blend was designed to exhibit a double-continuity structure i.e., the CB particles form chain-like network structures within the TPU phase, which forms a continuous phase within the HIPS matrix. Extruded HIPS/TPU/CB filaments produced by a capillary rheometer process at various shear rate levels were used for the sensing experiments. All filaments displayed a selective resistance changes upon exposure to the various alcohols combined with reproducibility and recovery behaviour. An attempt is made to identify the dominant mechanisms controlling the sensing process in a CB-containing immiscible polymer blend characterized by a double-continuity structure. The distinct structure and composition of the HIPS/TPU interphase region were found to have a crucial role in the sensing mechanism, determining the selectivity of the filaments toward the studied alcohols. Additionally, the sensing performance of HIPS/TPU/CB system is compared to recent results for TPU/CB compounds, polypropylene/TPU/CB and HIPS/ethylene vinyl acetate/CB immiscible polymer blends.  相似文献   
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OBJECTIVE: To assess the role of DNA ploidy as a predictor of radioresistance in T1 glottic carcinoma. DESIGN: Case-control study. Flow cytometric DNA ploidy measurements were performed on formalin-fixed paraffin-embedded tumor specimens from 15 patients with T1 glottic laryngeal carcinomas in whom radiotherapy had failed and from a matched group of 15 patients in whom an identical radiotherapy regimen was curative. Analysis of DNA content was performed blind to outcome of treatment. SETTING: Academic tertiary referral medical center. PARTICIPANTS: Thirty patients with clinically staged T1, N0, M0 glottic carcinoma. INTERVENTION: All patients received radiation to the larynx through opposed lateral ports at a total dose of 64 to 70 Gy. RESULTS: Ten diploid and five aneuploid histograms were found in the resistant group, and six diploid and nine aneuploid histograms were found in the radiosensitive group. This difference was not statistically significant. A trend toward a higher relapse rate after radiotherapy (62.5%) among patients with diploid tumor compared with those with aneuploid tumor (35.7%) was noted. CONCLUSIONS: DNA ploidy did not predict response to radiotherapy in patients with T1 glottic cancer, probably because of the small number of patients. A trend toward lower risk of local recurrence after radiotherapy in aneuploid tumors was noted. A larger prospective study is needed to assess the value of DNA ploidy in the treatment of early laryngeal cancer.  相似文献   
5.
Cu/Zn superoxide dismutase (Cu/Zn SOD) is a key enzyme in the metabolism of oxygen free radicals. The gene resides on chromosome 21 and is overexpressed in patients with Down syndrome. Cultured neurons of transgenic Cu/Zn SOD (Tg-Cu/Zn SOD) mice with elevated activity of Cu/Zn SOD were used to determine whether constitutive overexpression of Cu/Zn SOD creates an indigenous oxidative stress that predisposes the Tg-Cu/Zn SOD neurons to added insults. Neurons from three independently derived Tg-Cu/Zn SOD strains showed higher susceptibility than nontransgenic neurons to kainic acid (KA)-mediated excitotoxicity, reflected by an earlier onset and enhanced apoptotic cell death. This higher susceptibility of transgenic neurons to KA-mediated apoptosis was associated with a chronic prooxidant state that was manifested by reduced levels of cellular glutathione and altered [Ca2+]i homeostasis. The data are compatible with the thesis that overexpression of Cu/Zn SOD creates chronic oxidative stress in the transgenic neurons, which exacerbates their susceptibility to additional insults such as KA-mediated excitotoxicity.  相似文献   
6.
Responds to the points made by R. Cropanzano and K. James (see record 1991-00462-001) concerning the article by R. D. Arvey et al (1989). The authors acknowledge that the Arvey et al study is based on a single design, makes use of a small and special sample, and, as such, is vulnerable to threats of internal and external validity. Nevertheless, after providing a more comprehensive conceptual and empirical context for the study, and after reviewing a number of the issues raised by Cropanzano and James, the authors conclude that it is not premature to accept the idea that work attitudes are partially genetically influenced. Indeed, the authors use behavioral genetic theory, together with data gathered in the Arvey et al study, to make specific point predictions regarding the outcomes of an array of studies that easily can be undertaken. Finally, the authors acknowledge that the comments and issues raised by Cropanzano and James, along with the interchange, can offer directions for future research in this important area. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We administered the Multidimensional Personality Questionnaire (MPQ) to 217 monozygotic and 114 dizygotic reared-together adult twin pairs and 44 monozygotic reared-apart adult twin pairs. A four-parameter biometric model (incorporating genetic, additive versus nonadditive, shared family-environment, and unshared environment components) and five reduced models were fitted through maximum-likelihood techniques to data obtained with the 11 primary MPQ scales and its 3 higher order scales. Solely environmental models did not fit any of the scales. Although the other reduced models, including the simple additive model, did fit many of the scales, only the full model provided a satisfactory fit for all scales. Heritabilities estimated by the full model ranged from .39 to .58. Consistent with previous reports, but contrary to widely held beliefs, the overall contribution of a common family-environment component was small and negligible for all but 2 of the 14 personality measures. Evidence of significant nonadditive genetic effects, possibly emergenic (epistatic) in nature, was obtained for 3 of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
We studied 17 pedigrees with 108 affected males with X-linked juvenile retinoschisis (RS; McKusick No. 31270) and have analyzed all of the known polymorphic markers in the RS region of Xp22.1-p22.2 between DXS987 and DXS41. By haplotype analyses we found 7 individuals who showed crossovers in this interval surrounding RS. We previously reported AFM291wf5 as the centromeric boundary, and this remains unchanged in the present study. A new recombination was identified on the telomeric side at (DXS1195, DXS418). Our data support the locus order Xpter--(DXS987, DXS207, DXS1053, DXS43)--(DXS1195, DXS418)--(RS, DXS257, DXS999)--(AFM291wf5, DXS443)--DXS1052--(DXS1226, DXS274, DXS41)--Xcen; loci grouped in parentheses could not be mutually ordered by our genetic data. Physical mapping has indicated a distance of at most 900-1,000 kb between (DXS1195, DXS418) and AFM291wf5. No recombination was observed between RS and DXS257 which lies in our new interval of interest, but one critical individual was not informative with this marker. Our data now define the smallest RS inclusion interval. This interval is contained on a single YAC from which we have identified expressed sequences as candidate genes for RS.  相似文献   
10.
Automated regression suites are essential in developing large applications, while maintaining reasonable quality and timetables. The main argument against the automation of regression suites, in addition to the cost of creation and maintenance, is the observation that if you run the same test many times, it becomes increasingly less likely to find bugs. To alleviate such problems, a new regression suite practice, using random test generators to create regression suites on-the-fly, is becoming more common. In this practice, instead of maintaining tests, we generate test suites on-the-fly by choosing several specifications and generating a number of tests from each specification.  相似文献   
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