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Reports an error in "Does Barbie make girls want to be thin? The effect of experimental exposure to images of dolls on the body image of 5- to 8-year-old girls" by Helga Dittmar, Emma Halliwell and Suzanne Ive (Developmental Psychology, 2006 Mar, Vol 42[2], 283-292). A substantive error occurs in the Body shape dissatisfaction section on page 287. The sentence describing the calculation of body shape dissatisfaction scores from girls' responses to the Child Figure Rating Scale should instead read as follows: "A body shape dissatisfaction score was computed by subtracting the girl's actual from her ideal body size." (The following abstract of the original article appeared in record 2006-03514-007.) The ubiquitous Barbie doll was examined in the present study as a possible cause for young girls' body dissatisfaction. A total of 162 girls, from age 5 to age 8, were exposed to images of either Barbie dolls, Emme dolls (U.S. size 16), or no dolls (baseline control) and then completed assessments of body image. Girls exposed to Barbie reported lower body esteem and greater desire for a thinner body shape than girls in the other exposure conditions. However, this immediate negative impact of Barbie doll was no longer evident in the oldest girls. These findings imply that, even if dolls cease to function as aspirational role models for older girls, early exposure to dolls epitomizing an unrealistically thin body ideal may damage girls' body image, which would contribute to an increased risk of disordered eating and weight cycling. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In this paper, the diagnosability of n-dimensional star graph Sn under the comparison diagnosis model has been studied. It is proved that Sn is (n−1)-diagnosable under the comparison diagnosis model when n?4. 相似文献
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This article presents an elaborated model of organizational regression suggesting that, within the framework of general systems and catastrophe theory, organizational units and whole enterprises can be viewed as struggling to attain a state of super-resilience that enables them to cope effectively with a large number of regressive forces. The model comprises 6 phases of organizational regression that occur either in a 10-stage process or in a chaotically unpredictable but behaviorally understandable and orderly sequence. Internal and external regressive forces that constantly pressure an organization toward less effective performance and more primitive behavior are identified. Organizational barriers and balancing forces that counter the regressive pressures are also described, along with the consequences of regression for individuals and enterprises. Several brief case illustrations (e.g., Montgomery Ward, Apple Computer, and General Electric Corporation) are provided to highlight aspects of this conceptual approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In a study of pigs slaughtered at British abattoirs, approximately 23% carried Salmonella in their cecal (large intestine) contents. The most frequent serotype was Salmonella Typhimurium (STM), which was the second most common cause of human salmonellosis in Great Britain. A pig industry-monitoring program was developed to reduce Salmonella infection on British farms. The control of STM infection on the farm requires an understanding of STM transmission dynamics within the herd, and a mathematical model has been developed for an infected grower-finisher farm. The model estimates the probability of a random pig being infected with STM. There are three broad categories of STM infection in pigs: pigs that are infected but unable to transmit the infection (latent); pigs that are infectious, i.e., able to transmit the infection (shedders); and pigs that have stopped shedding but harbor STM in their internal organs (carriers). The model estimates that 21.0% (5th and 95th percentiles, 0.05 to 77.5%) of slaughter-age pigs on an infected farm are likely to be shedding STM. Although this range is wide, it is biologically plausible. Sensitivity analysis of the total number of infected pigs revealed that the most significant input parameters are the probability of effective contact between a specific infectious and susceptible pig and the duration of shedding. The model predicted that 11.5% of pigs would be shedding STM at slaughter age. This value is close to the estimate obtained from a British abattoir survey that 11. 1% of pigs carried STM in their ceca, indicating that the model has reasonable validity. 相似文献
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Isotopic variations of Zn in biological materials 总被引:3,自引:0,他引:3
Stenberg A Andrén H Malinovsky D Engström E Rodushkin I Baxter DC 《Analytical chemistry》2004,76(14):3971-3978
Variations in the isotopic composition of Zn present in various biological materials were determined using high-resolution multicollector inductively coupled plasma mass spectrometry (MC-ICPMS), following digestion and purification by anion exchange chromatography. To correct for differences in instrumental mass discrimination effects between samples and standards, Cu was employed as an elemental spike. Complementary analyses of Zn separates by sector field ICPMS instruments revealed that the concentrations of the majority of potentially interfering elements were reduced to negligible levels. Residual spectral interferences resulting from (35)Cl(16)O(2)(+), (40)Ar(14)N(2)(+), and (40)Ar(14)N(16)O(+) could be instrumentally resolved from the (67)Zn, (68)Zn, and (70)Zn ion beams, respectively, during measurement by MC-ICPMS. The only other observed interference in the Cu and Zn mass range that could not be effectively eliminated by high-resolution multicollection resulted from (35)Cl(2)(+), necessitating modification of the sample preparation procedure to allow accurate (70)Zn detection. Complete duplication of the entire analytical procedure for human whole blood and hair, as well as bovine liver and muscle, provided an external reproducibility of 0.05-0.12 per thousand (2sigma) for measured delta(66/64)Zn, delta(67/64)Zn, and delta(68/64)Zn values, demonstrating the utility of the method for the precise isotopic analysis of Zn in biological materials. Relative to the selected Zn isotopic standard, delta(66/64)Zn values for biological samples varied from -0.60 per thousand in human hair to +0.56 per thousand in human whole blood, identifying the former material as the isotopically lightest Zn source found in nature to date. 相似文献
48.
Pugh E 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2003,361(1813):2715-2729
Superconductors have many unusual properties not observed in normal metals. The superconducting state is attributed to the pairing of electrons. Conventional forms of superconductivity are produced by distortions in the underlying crystal structure of the material. Recently, it has become evident that not all forms of superconductivity can be explained in this way. The way pairing occurs has to be redressed in these materials. Of particular interest is the interplay between magnetism and superconductivity and the consequences this may have on pair formation. 相似文献
49.
Subtissue Imaging and Thermal Monitoring of Gold Nanorods through Joined Encapsulation with Nd‐Doped Infrared‐Emitting Nanoparticles 下载免费PDF全文
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