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This meta-analytic review (k = 62 studies; N = 7,613 mother-child dyads) shows that effect sizes for the association between child negative emotionality and parenting were generally small and were moderated by sample and measurement characteristics. The association between more child negative emotionality and less supportive parenting was relatively strong in lower socioeconomic status families, reversed in higher socioeconomic status families, and limited to studies with relatively high percentages of participants from ethnic minorities and studies using parent report to assess negative emotionality. Higher levels of child negative emotionality were associated with more restrictive control in samples with less than 75% 1st-born children, as well as in infants and preschoolers, and in studies using parent report or composite measures to assess both negative emotionality and restrictive parenting. Finally, more child negative emotionality was associated with less inductive control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Background  

During the last years engineered nanoparticles (NPs) have been extensively used in different technologies and consequently many questions have arisen about the risk and the impact on human health following exposure to nanoparticles. Nevertheless, at present knowledge about the cytotoxicity induced by NPs is still largely incomplete. In this context, we have investigated the cytotoxicity induced by gold nanoparticles (AuNPs), which differed in size and purification grade (presence or absence of sodium citrate residues on the particle surface) in vitro, in the human alveolar type-II (ATII)-like cell lines A549 and NCIH441.  相似文献   
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Thermoelectric properties of Au-substituted Si-based clathrates, Ba8AuGa13Si32 and Ba6A2AuGa x Si45−x (A = Sr, Eu, = 13, 14), were experimentally and theoretically investigated. The polycrystalline samples of the Au-substituted Si-based clathrates were prepared by using the spark plasma sintering technique. The electronic structure of Ba6A2AuGa13Si32 was theoretically calculated by ab initio calculations, and the thermoelectric properties of Ba6A2AuGa x Si45−x were estimated through the calculated electronic structure. The effective mass of Ba6A2AuGa x Si45−x was experimentally estimated to be greater than that of Ba8AuGa13Si32. Experimentally observed electronic properties agree with the calculations for Ba6A2AuGa x Si45−x . The maximum ZT value of Ba6Sr2AuGa14Ge31 is about 0.5 at 850 K. The calculated thermoelectric properties agree very well with the experimental results in the range from room temperature to 900 K.  相似文献   
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Skin colour assessment in safety testing of cosmetics. An overview   总被引:1,自引:0,他引:1  
Synopsis
Few subjects are as problematical to dermatologists, cosmetologists and related experimenters involved in safety testing as the clinical assessment of skin colour. At the core of the problem is the word erythema, which does not communicate a sense for the nuance of red. In addition, light shades of red are not visible in dark-skinned people. Human assays aiming at evaluating the irritancy and allergic potential of cosmetics take advantage to use instrumental assessments of skin colour. However, there are pitfalls related to the complex biological aspects of the cutaneous reactivity, to the design of the in vivo assay, and to technical aspects bound to the principle of the measuring methods. Sound information can only be reached when these concerns are solved.
Résumé
Peu de sujets sont aussi problématiques pour les dermatologues, cosmétologues et autres expérimentateurs impliqués dans les tests de sûreté que l'évaluation clinique des couleurs cutanées. Au centre du problème est le mot érythème qui ne communique pas la notion des nuances de rouge. De plus, un érythème discret peut ne pas être visible chez des individus à la peau foncée. Les tests humains visant àévaluer les potentialités d'irritation et d'allergie aux cosmétiques bénéficient des évaluations instrumentales de la couleur cutanée. Cependant, il existe des pièges liés aux aspects biologiques complexes de la réactivité cutanée, au choix du test in vivo et à des aspects techniques en relation avec le principe du système de mesure. Une information adéquate ne peut être obtenue qu'après avoir résolu ces problèmes.  相似文献   
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Eingegangen am 23.03.1995, in überarbeiteter Form am 12.07.1995  相似文献   
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The temperature and pH-dependence of the swelling of acid-processed gelatin was investigated. For stabilisation of the samples glyoxal was added as crosslinking agent. Swelling of the samples at different temperatures leads to different crosslinking densities. Degradation of network at temperatures higher than 10°C produces a time dependence of measured values. For the determination of the equilibrium swelling curve an extrapolation method was developed to eliminate the time dependence and to relate the degrees of swelling to constant crosslinking density. The slope of the equilibrium swelling curve shows deswelling of gelatin in water with increasing temperature. Using the equation between the slope of the swelling curve and the differential partial molar enthalpy of the solvent at the swelling maximum derived from the equilibrium condition for the chemical potential of the solvent an exothermic behaviour was found. pH-dependence of swelling corresponds qualitatively with Flory's theory. Hydrolysis in the alkaline region is much stronger than in the acid region. At pH = 12,8 hydrolysis increases sharply.  相似文献   
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