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61.
Blatt Sidney J.; Quinlan Donald M.; Chevron Eve S.; McDonald Cathy; Zuroff David 《Canadian Metallurgical Quarterly》1982,50(1):113
Two independent types of experiences of depression have been identified among normals—dependency and self-criticism. Using the Depressive Experiences Questionnaire, this study investigates their utility in differentiating depression in patients. 197 patients (mean age 34 yrs) and 262 normal controls (mean age 26.7 yrs) also completed the MMPI, Beck Depression Inventory, and Self Rating Depression Scale. There were consistent differences among patients as a function of whether their experiences of depression focused primarily on issues of dependency and/or self-criticism or an absence of these issues. The subjective experiences around which an individual's depression focuses seem to provide a valid basis for differentiating among types of depression. Judges using case records were able to differentiate patients who were high on dependency or self-criticism, on both, or on neither of these dimensions. The distinction between these 2 different foci of depression may provide valuable differentiations for clinical research, and have important implications for the therapeutic process with different types of depressed patients. (55 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Christian Larrigaudière Rosa Vilaplana Inmaculada Recasens Yolanda Soria Eve Dupille 《Journal of the science of food and agriculture》2010,90(14):2379-2385
BACKGROUND: ‘Diffuse skin browning’ (DSB) is a physiological disorder that affects Golden Delicious apples treated with 1‐methylcyclopropene (1‐MCP). Although a very high incidence is found, very little is known about the etiology of this disorder. This study aims to provide an understanding of the causes of this disorder and prevent it. RESULTS: A very high incidence of DSB was found in 1‐MCP‐treated apples independent of the location of the orchard. Similar to superficial scald, harvest maturity determines the DSB incidence, with the more mature fruit being less sensitive. The 1‐MCP dose (156 nL L?1 or 625 nL L?1) and the temperature at which the 1‐MCP treatment was applied (0.5 or 20 °C) did not affect the incidence of DSB. Diphenylamine (DPA) treatment did not prevent DSB, contrary to superficial scald. Additionally, controlled atmosphere storage only partially reduced the incidence of DSB, whereas progressive cooling strategies completely inhibited DSB occurrence. A direct correlation was found between the sensitivity of the Golden Delicious clone to russeting and its sensitivity to develop DSB during storage. CONCLUSION: Our results indicated that DSB and superficial scald are two different disorders involving different oxidative processes. DSB can be prevented by progressive cooling and selection of russeting‐resistant clones. Copyright © 2010 Society of Chemical Industry 相似文献
63.
Rahul Vanam Eve A. Riskin Richard E. Ladner Sheila S. Hemami 《Signal, Image and Video Processing》2013,7(5):991-1003
The H.264/AVC standard significantly improves video compression performance over earlier standards at the cost of increased complexity. In this paper, we present two offline algorithms for generating a lookup table of parameter settings that can be used by a complexity control algorithm for controlling the speed of the H.264 encoder. Our algorithms to design the lookup table of parameter settings take fewer than 2% of the number of encodings required by an exhaustive search of all possible parameter settings and find parameter settings that offer high peak signal-to-noise ratio (PSNR) with low encoding time at a given bitrate. Our parameter settings are fairly robust over different videos and bitrates. We focus on low-resolution videos at bitrates less than 300 kb/s. We compare the performance of our algorithms to both exhaustive search and a multiobjective optimization algorithm. Our parameter settings improve the average encoding speed over the default parameter setting of the x264 encoder on both PC and cell phone platforms by up to 37.4 and 94.1%, respectively, with PSNR difference of up to 0.3 dB. 相似文献
64.
Metal ions (Ag+, Cu2+, Hg2+) are incorporated into an electropolymerized, poly(N‐isopropyl acrylamide), pNIPAM, thermosensitive polymer associated with an electrode using the “breathing‐in” method. The ion‐functionalized pNIPAM matrices reveal ion‐dependent gel‐to‐solid phase‐transition temperatures (28 ± 1 °C, 25 ± 1 °C, 40 ± 1 °C for the Ag+, Cu2+, and Hg2+‐modified pNIPAM, respectively). Furthermore, the ion‐functionalized polymers exhibit quasi‐reversible redox properties, and the ions are reduced to the respective Ag0, Cu0, and Hg0 nanocluster‐modified polymers. The metal‐nanocluster‐functionalized pNIPAM matrices enhance the electron transfer (they exhibit lower electron‐transfer resistances) in the compacted states. The electron‐transfer resistances of the metal‐nanocluster‐modified pNIPAM can be cycled between low and high values by temperature‐induced switching of the polymer between its contracted solid and expanded gel states, respectively. The enhanced electron‐transfer properties of the metal nanocluster‐functionalized polymer are attributed to the contacting of the metal nanoclusters in the contracted state of the polymers. This temperature‐switchable electron transfer across a Ag0‐modified pNIPAM was implemented to design a thermo‐switchable electrocatalytic process (the temperature‐switchable electrocatalyzed reduction of H2O2 by Ag0‐pNIPAM). 相似文献
65.
Variable rate vector quantization for medical image compression 总被引:1,自引:0,他引:1
Three techniques for variable-rate vector quantizer design are applied to medical images. The first two are extensions of an algorithm for optimal pruning in tree-structured classification and regression due to Breiman et al. The code design algorithms find subtrees of a given tree-structured vector quantizer (TSVQ), each one optimal in that it has the lowest average distortion of all subtrees of the TSVQ with the same or lesser average rate. Since the resulting subtrees have variable depth, natural variable-rate coders result. The third technique is a joint optimization of a vector quantizer and a noiseless variable-rate code. This technique is relatively complex but it has the potential to yield the highest performance of all three techniques. 相似文献
66.
Srinivas B.S. Ladner R.E. Azizoglu M. Riskin E.A. 《IEEE transactions on image processing》1999,8(4):462-475
We propose a new maximum a posteriori (MAP) detector, without the need for explicit channel coding, to lessen the impact of communication channel errors on compressed image sources. The MAP detector exploits the spatial correlation in the compressed bitstream as well as the temporal memory in the channel to correct channel errors. We first present a technique for computing the residual redundancy inherent in a compressed grayscale image (compressed using VQ). The performance of the proposed MAP detector is compared to that of a memoryless MAP detector. We also investigate the dependence of the performance on memory characteristics of the Gilbert-Elliott channel as well as average channel error rate. Finally, we study the robustness of the proposed MAP detector's performance to estimation errors. 相似文献
67.
To use wavelet packets for lossy data compression, the following issues must be addressed: quantization of the wavelet subbands, allocation of bits to each subband, and best-basis selection. We present an algorithm for wavelet packets that systematically identifies all bit allocations/best-basis selections on the lower convex hull of the rate-distortion curve. We demonstrate the algorithm on tree-structured vector quantizers used to code image subbands from the wavelet packet decomposition. 相似文献
68.
Cosman PC Tseng C Gray RM Olshen RA Moses LE Davidson HC Bergin CJ Riskin EA 《IEEE transactions on medical imaging》1993,12(4):727-739
The authors apply a lossy compression algorithm to medical images, and quantify the quality of the images by the diagnostic performance of radiologists, as well as by traditional signal-to-noise ratios and subjective ratings. The authors' study is unlike previous studies of the effects of lossy compression in that they consider nonbinary detection tasks, simulate actual diagnostic practice instead of using paired tests or confidence rankings, use statistical methods that are more appropriate for nonbinary clinical data than are the popular receiver operating characteristic curves, and use low-complexity predictive tree-structured vector quantization for compression rather than DCT-based transform codes combined with entropy coding. The authors' diagnostic tasks are the identification of nodules (tumors) in the lungs and lymphadenopathy in the mediastinum from computerized tomography (CT) chest scans. Radiologists read both uncompressed and lossy compressed versions of images. For the image modality, compression algorithm, and diagnostic tasks the authors consider, the original 12 bit per pixel (bpp) CT image can be compressed to between 1 bpp and 2 bpp with no significant changes in diagnostic accuracy. The techniques presented here for evaluating image quality do not depend on the specific compression algorithm and are useful new methods for evaluating the benefits of any lossy image processing technique. 相似文献
69.
Studied sex differences and sex role correlates of depressive experiences in 82 female and 39 male college students. Gender differences in depressive experiences were found. These differences were consistent with societal sex role expectations. The level of depression on the Zung Self-Rating Depression Scale was negatively associated with sex role congruence, as assessed by the Sex-Role Stereotype Questionnaire, scored for Competency and Warmth–Expressiveness. Degree of sex role congruence within the male and female samples was also associated with different depressive experiences on the Depressive Experiences Questionnaire. The sex differences and the different intrasex correlations indicated that experiences of depression are associated with different facets of sex role stereotypes. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Ashmead Daniel H.; Clifton Rachel K.; Perris Eve E. 《Canadian Metallurgical Quarterly》1987,23(5):641
The precision of auditory localization in 26- to 30-week old infants was measured with a test based on the adult minimum audible angle. In this test, the horizontal angle between loudspeakers was varied systematically to determine thresholds for discriminating rightward versus leftward sound displacements. Infants were presented with sounds that shifted from straight ahead to the left or right, and observers judged from the infants' eye and head movements to which side the sound had shifted. From trial to trial, the size of the shift was decreased after correct responding and increased after incorrect responding. Infants discriminated sound displacements of about 19°, considerably less accurate than adult values of 1–2°. These findings are discussed in terms of their methodological implications and the development of sensitivity to information for sound localization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献