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The main aim of this study was to analyze the psychometric properties of the Children's Surgical Worries Questionnaire developed by Quiles, Mendez, and Hidalgo (1999). We applied the questionnaire to a representative sample of 1,311 Spanish-speaking, elementary school students. The exploratory factor analysis isolated only 1 factor-corroborated by the confirmatory factor analysis-Children Surgical Worries, which included 17 items and accounted for the 22.13% of the variance. Internal consistency (.83) and test-retest reliability with a 7- to 10-day interval (.90) were satisfactory. Surgical worries correlated positively with medical fears (.60). The most worrisome situations for children were those related to the negative repercussions of surgery, pain, and separation from parents. Girls (p = .000) and children who had never had an operation (p = .005) presented a higher degree of surgical worries. No statistically significant differences were found regarding age nor the interaction of gender, age, and surgical experience variables. [ABSTRACT FROM AUTHOR]

Purpose:This study seeks to compare functional modifications of the plasma membrane induced either by water radiolysis (80kV X-rays) or by visible light in the presence of the photosensitizer photofrin II. The two methods generate different kinds of free radicals and other reactive species such as singlet oxygen. Their effect on the electrical properties of the plasma membrane is investigated. Method: The patch-clamp technique (whole-cell and inside-out configuration) was applied to the plasma membrane of an epithelial cell line (opossum kidney (OK) cells). Results: Generation of the reactive species gave rise to a decay of the membrane potential, to an inactivation of K-channels, and to an increase of the leak conductance of the membrane. All three effects were strongly involved in photomodification of the membrane. Following X-ray exposure (doses up to 1000Gy) on the other hand, the decay of the membrane conductance caused by inactivation of ion channels was predominant, while the increase of the leak conductance and the depolarization were comparatively minor responses. Conclusion: Photomodification of the plasma membrane by visible light in the presence of the membrane-active sensitizer photofrin II is of considerably greater consequence for the electrical properties of the membrane, compared with exposure to ionizing radiation of the membrane and its aqueous environment. The differences are thought to reflect the types of reactive species produced by the two methods and their site of generation. [ABSTRACT FROM AUTHOR]

The classical problem of the ignition and flame generation of combustible premixed gases by a hot flat plate is analyzed by asymptotic techniques for moderate values of the Zeldovich numbers. For temperatures of the plate smaller than the adiabatic flame temperature it was found that the corrections to the zeroth-order solution (Zeldovich approximation) are very important for finite Zeldovich numbers. The asymptotic analysis was carried out with the inclusion of reactant consumption showing different responses depending if the reactant consumption parameter is larger or smaller than a critical one. For temperatures of the plate larger than the adiabatic flame temperatures (that is, the reactant consumption parameter larger than the critical one), the ignition is not characterized by a thermal runaway and a smooth transition from frozen to equilibrium flow is obtained. The evolution towards the premixed flame formation is analyzed and the flame position and flame temperature are obtained. [ABSTRACT FROM PUBLISHER]