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71.
Observers consciously prefer Mondrian's paintings in their original orientation compared with a rotated position—the “oblique effect” (Latto, Brain, & Kelly, 2000). However, this finding's premise, that all vertical–horizontal orientations of the thick black lines in Mondrian's oeuvre are preferred, overlooks the fact that the overall balance of these images is also altered when they are reoriented. Thus, balance may regulate the oblique effect, which might influence conscious aesthetic preferences. To address this issue, we explore Hess's (1965, 1972) claim that observers will unconsciously increase their pupil diameter to pleasing images and constrict it to unpleasant images. We overcame Hess's methodological limitation of not keeping his images' luminances and contrast constant across conditions by presenting eight Mondrian paintings (1921–1944) to 30 observers on a CRT for 20 s each in either their original or seven rotated positions. Simultaneously, we measured their pupil size while asking them to report how (dis)pleasing they found each image. We found both evidence for the oblique effect (where image rotation hampers preference) and a correlation between this consciously reported aesthetic preference and unconsciously derived pupil size. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
To measure exploratory play at 1 yr of age, 41 middle-class infants were observed in a free-play setting. In a separate session, 11 structured tasks assessed the infants' persistence in mastering tasks. In a 3rd session, the Bayley Scales of Infant Development were given. As part of another study, home observations were available for 40 of the infants at 1 yr of age and for 23 of the infants at 6 mo of age. Measures of quantitative aspects of exploratory play showed no relationship to persistence or cognitive development; however, measures indexing the quality of exploratory play did. In addition, environmental measures at both 6 and 12 mo were related to exploratory play at 1 yr, particularly to the production of perceptual effects; but some of these findings were opposite to those expected. Results suggest that the quality of exploratory play, rather than the quantity, is a better index of underlying mastery motivation. In addition, the widely accepted assumption of a link between the amount of general exploration and cognitive ability needs to be reexamined. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
Object-oriented change detection for the city of Harare,Zimbabwe   总被引:1,自引:0,他引:1  
Object building and the extraction of homogeneous landscape units on which spatial statistics can be applied is useful in assessing land use and land cover change. Object-oriented processing techniques are becoming more popular compared to traditional pixel-based image analysis. A hierarchical image segmentation approach was adopted to extract the objects from multi-temporal Landsat images over Zimbabwe. The spatial arrangement of t0 and t1 objects was independent as the segmentation process was independently applied, although object change of t1 was based on t0 boundaries. We applied a Standardized, Object Oriented, Automatic Classification (SOOAC) method based on fuzzy logic. The error matrix for the TM image had an overall accuracy of 95.6% and a KIA value of 94.7%, the ETM showed slightly lower overall accuracy. Various LULC changes were identified over the 13 year period per object and also per class, mainly vegetation decrease. Object-oriented change information is necessary in decision support systems and uncertainty management strategies. This approach addresses some of the major issues in object-based GIS change analysis as it is based on stable object geometry.  相似文献   
74.
Soft lactic cheeses were manufactured with raw goat milk inoculated with Listeria monocytogenes. The physico-chemical and microbiological characteristics of curds and cheeses were determined after each processing step as well as during ripening and refrigerated storage. The fate of Listeria monocytogenes was evaluated by enumeration on PALCAM agar and by a qualitative detection after a double selective enrichment procedure. The results showed that the physico-chemical and microbiological characteristics of lactic cheeses caused a decrease of Listeria monocytogenes counts. However, this decrease did not lead to the complete disappearance of the pathogen and Listeria monocytogenes was able to survive in soft lactic cheeses made with raw goat milk.  相似文献   
75.
The effect of thermosonication (TS) and pulsed electric fields (PEF) on inactivation of Staphylococcus aureus (SST 2.4) and selected quality aspects in orange juice was investigated. Conventional pasteurization (HTST, 94 °C for 26 s) was used as a control. TS (10 min at 55 °C) applied in combination with PEF (40 kV/cm for 150 μs) resulted in a comparable inactivation of S. aureus to that achieved by conventional HTST. TS/PEF did not affect the pH, conductivity, or °Brix and had a milder impact on the juice color than thermal treatment. Furthermore, the non-enzymatic browning index was significantly affected by HTST (P < 0.05) but not by TS and PEF. Ascorbic acid retention was almost complete after TS and PEF (96.0%), but it was substantially lower (P < 0.05) after HTST (80.5%). Residual activity of pectin methyl esterase (PME) decreased as PEF field strength and treatment time increased; however, applying TS and PEF in combination left a greater residual PME activity than HTST (12.9 vs 5.0%, respectively).  相似文献   
76.
Ion beam enhanced deposition (IBED) was adopted to synthesize biocompatible titanium oxide film. Structure characteristics of titanium oxide film were investigated by RBS, AES, and XRD. The blood compatibility of the titanium oxide film was studied by measurements of blood clotting time and platelet adhesion. The results show that the anticoagulation property of titanium oxide film is improved significantly. The mechanism of anticoagulation of the titanium oxide film was discussed.  相似文献   
77.
Antibodies were used to probe the degree of association of starch biosynthetic enzymes with starch granules isolated from maize (Zea mays) endosperm. Graded washings of the starch granule, followed by release of polypeptides by gelatinization in 2% sodium dodecyl sulfate, enables distinction between strongly and loosely adherent proteins. Mild aqueous washing of granules resulted in near-complete solubilization of ADP-glucose pyrophosphorylase, indicating that little, if any, ADP-glucose pyrophosphorylase is granule associated. In contrast, all of the waxy protein plus significant levels of starch synthase I and starch branching enzyme II (BEII) remained granule associated. Stringent washings using protease and detergent demonstrated that the waxy protein, more than 85% total endosperm starch synthase I protein, and more than 45% of BEII protein were strongly associated with starch granules. Rates of polypeptide accumulation within starch granules remained constant during endosperm development. Soluble and granule-derived forms of BEII yielded identical peptide maps and overlapping tryptic fragments closely aligned with deduced amino acid sequences from BEII cDNA clones. These observations provide direct evidence that BEII exits as both soluble and granule-associated entities. We conclude that each of the known starch biosynthetic enzymes in maize endosperm exhibits a differential propensity to associate with, or to become irreversibly entrapped within, the starch granule.  相似文献   
78.
OBJECTIVE: The purpose of our study was to review and report the patient selection, techniques, and results of percutaneous drainage of pancreatic abscesses by retrospective review. MATERIALS AND METHODS: Fifty-nine patients (46 men and 13 women) with a mean age of 44 years old had 80 pancreatic abscesses that were drained percutaneously under radiologic guidance (CT, n = 77; sonography, n = 2; and fluoroscopy, n = 1). Abscesses had a wide spectrum of causes, with alcoholic pancreatitis being most common, trauma second most common, and gallstones third. Ten patients had undergone surgery for pancreatic necrosis or abscess. Patients with pancreatic pseudocysts, necrosis, or acute fluid collections were excluded from this study. RESULTS: Of the 59 patients, 51 (86%) were cured with percutaneous drainage and antibiotic therapy. Of the patients who were not cured with percutaneous drainage, seven required surgery and one underwent repeat percutaneous drainage. In the 59 patients, complications included non-life-threatening bleeding in three patients. Ten of 59 patients (17%) had fistulas that spontaneously formed into the gastrointestinal tract. The duration of catheterization ranged from 4 to 119 days, with a mean duration of 33 days. The rate of mortality at 30 days after completion of percutaneous drainage was 8% (5 of 59). CONCLUSION: Percutaneous drainage was an effective therapy for this defined group of patients with pancreatic abscesses. Factors leading to the relatively high success rate described in this study likely included selection of patients; catheters of adequate size, number, and location; careful follow-up with appropriate catheter manipulations; and an integrated, cooperative approach whereby surgeons were willing to permit drainage to effect its benefits, rather than operating prematurely.  相似文献   
79.
The sodium disilicate-barium disilicate join of the ternary system, Na2O-BaO-SiO2, has been studied by means of the quenching method, and the phase-equilibrium diagram has been determined. The two compounds form a binary system without intermediate compounds and without appreciable solid solution. The eutectic occurs at approximately 32% of barium disilicate by weight and at a temperature of 797° C. The melting point of barium disilicate was determined as 1418° C. The glasses in the field of stability of barium disilicate show a marked tendency toward devitrification. The refractive indices of the glasses for sodium light were measured by the microscopic immersion method. These varied regularly from 1.505 for sodium disilicate glass to 1.610 for barium disilicate glass. The refractive index-composition curve plotted on a weight percentage basis is definitely convex downward, whereas on a mol percentage basis it is slightly convex upward.  相似文献   
80.
The dielectric constants, densities, and refractive indices of two series of soda-boro-silicate glasses were measured at 25° C. on some quenched specimens and on other specimens that were stabilized at different temperatures. The compositions of the two series were Na2O-4.69 SiO2-B2O, (0 to 45%) and Na2O B2O3-SiO2 (30 to 100%), respectively. The structure of the glasses was found to depend on the ratio of oxygen atoms to the sum of the boron and silicon atoms and also on the concentration of the sodium ions. If the ratio of O to B + Si is greater than 2.0 or if the ratio of oxygen to sodium ions is less than 6.0, some of the oxygens are bonded only to one boron or to one silicon atom. The presence of “single-bonded” oxygen atoms in the glass structure leads to a lower density and a higher dielectric constant and refractive index. The dielectric constant decreases and the density increases continuously as the temperature of heat treatment is lowered. The effect of heat treatment is greater for the glasses which contain the larger number of “single-bonded” oxygen atoms and the higher concentration of sodium ions.  相似文献   
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