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1.
One reason for the limited attention to existential psychology in child treatment is the assumption that children are restricted in the amount of freedom and responsibility they can assume. However, current research on child development reveals that children actively influence their social and physical environment and hence begin from birth the process of self-determination. This article presents guidelines for implementing existential psychology with children derived from theoretical tenets and case study findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Elaine F. Becker 《乙烯基与添加剂工艺杂志》1996,2(4):321-325
The introduction of low-price color systems, both quality control and color formulation, has brought affordability and practicality to the medium and small plastics companies. While color systems today are faster, cheaper, more accurate, easier to use than ever before, they are not that much more successful at doing what they were designed to do than they were 25 years ago. The pitfalls of start-up and implementation and the people problems have changed very little and are still a major factor in determining the degree of success. This paper discusses the ramifications of who is chosen to implement the system, what their charter is, and the resources that they are given. Factors to be considered and creating the right environment when implementing a color system are discussed. Some suggestions for planning a successful start-up and installation are given. 相似文献
3.
A Lanza S Tornaletti C Rodolfo MC Scanavini AM Pedrini 《Canadian Metallurgical Quarterly》1996,271(12):6978-6986
DNA topoisomerases have been proposed as the proteins involved in the formation of the DNA-protein cross-links detected after ultraviolet light (UV) irradiation of cellular DNA. This possibility has been investigated by studying the effects of UV-induced DNA damage on human DNA topoisomerase I action. UV lesions impaired the enzyme's ability to relax negatively supercoiled DNA. Decreased relaxation activity correlated with the stimulation of cleavable complexes. Accumulation of cleavable complexes resulted from blockage of the rejoining step of the cleavage-religation reaction. Mapping of cleavage sites on the pAT153 genome indicated UV-induced cleavage at discrete positions corresponding to sites stimulated also by the topoisomerase I inhibitor camptothecin, except for one. Subsequent analysis at nucleotide level within the sequence encompassing the UV-specific cleavage site revealed the precise positions of sites stimulated by camptothecin with respect to those specific for UV irradiation. Interestingly, one of the UV-stimulated cleavage sites was formed within a sequence that did not contain dimerized pyrimidines, suggesting transmission of the distortion, caused by photodamage to DNA, into the neighboring sequences. These results support the proposal that DNA structural alterations induced by UV lesions can be sufficient stimulus to induce cross-linking of topoisomerase I to cellular DNA. 相似文献
4.
5.
Modeling guided wave propagation with application to the long-range defect detection in railroad tracks 总被引:2,自引:0,他引:2
Ivan Bartoli Francesco Lanza di Scalea Mahmood Fateh Erasmo Viola 《NDT & E International》2005,38(5):325-334
The aim of this work is to demonstrate the use of a commercial finite element package, ABAQUS EXPLICIT, to model ultrasonic guided waves in structural components. The particular application of interest is modeling the interaction of a broadband vertical bending mode with transverse-type defects in railroad tracks. This topic is part of a broader project on high-speed defect detection in rails by long-range ultrasonic inspections. Reflection coefficient spectra in the 20–45 kHz range are obtained for four different sizes and three different orientations of transverse head flaws. A preliminary study of Lamb waves in a free plate helps drawing modeling guidelines for the rail. 相似文献
6.
M. F. Stroosnijder N. Zheng W. J. Quadakkers R. Hofman A. Gil F. Lanza 《Oxidation of Metals》1996,46(1-2):19-35
The effect of niobium implantation (2×1016 and 1017 ions/cm2) on the oxidation behavior of a -TiAl-based intermetallic alloy Ti–48Al–2Cr in air at 800°C has been examined. Isothermal studies with exposure times up to 200 hr and cyclic-oxidation tests up to 800 hr revealed a negligible effect for the low implantation dose. However, a remarkable decrease in oxidation rates was observed for the material implanted with 1017 Nb ions/cm2. The improvement in the oxidation resistance appeared to be similar to that obtained by alloying of the intermetallic with a few atomic percent niobium. Possible mechanisms for the effect of niobium on the oxidation resistance of TiAl-base intermetallics are discussed in view of the results obtained for the implanted material. 相似文献
7.
第一批人凝血因子Ⅶ浓制剂国家标准品协作标定 总被引:1,自引:0,他引:1
目的 协作标定第一批人凝血因子Ⅶ浓制剂国家标准品。方法 以 WHO 97/592批人凝血因子Ⅶ浓制剂国际标准品为对照,采用一期法标定我国首批人凝血因子Ⅶ因家标准品,并将标准品分别置4℃、22℃、37℃保存5个月,用加速破坏试验进行稳定性考查。结果 该批标准品效价为16.0IU/支,稳定性良好。其他项目均达到国家标准品要求。结论 已成功研制第一批人凝血因子Ⅶ浓制剂国家标准品。 相似文献
8.
Background
Leptin and its soluble receptor (sOB-R) are important to regulation of body composition but there are no data on the developmental variations in these plasma variables and their relationship with body composition measurements, 相似文献9.
Elaine C. Lopes Pereira Bluma G. Soares Adriana A. Silva Guilherme M. O. Barra 《应用聚合物科学杂志》2021,138(39):51164
Conducting polymer composites constituted by co-continuous poly (vinylidene fluoride) (PVDF)/ ethylene- vinyl acetate copolymer (EVA) blends with multiwalled carbon nanotube (CNT) were prepared by melt mixing using different procedures. The effect of the master batch approach on the conductivity, morphology, mechanical, thermal and rheological properties of PVDF/EVA/CNT nanocomposites was compared with that based on one step mixing strategy. The selective extraction experiments revealed that CNT was preferentially localized in the EVA phase in all situations, even when PVDF@CNT master batch was employed. Nanocomposites prepared with EVA@CNT master batch displayed higher conductivity, whose value reached around 10−1 S m−1 with the addition of 0.56 vol% of CNT. The better electrical performance was attributed to the better distribution of the filler, as indicated by transmission electron microscopy and rheological behavior. The electrical and rheological behavior were also investigated as a function of the CNT content. 相似文献
10.
The objectives of this study are to provide detailed information about green roof performance in the Mediterranean climate (retained volume, peak flow reduction, runoff delay) and to identify a suitable modelling approach for describing the associated hydrologic response. Data collected during a 13-month monitoring campaign and a seasonal monitoring campaign (September-December 2008) at the green roof experimental site of the University of Genova (Italy) are presented together with results obtained in quantifying the green roof hydrologic performance. In order to examine the green roof hydrologic response, the SWMS_2D model, that solves the Richards' equation for two-dimensional saturated-unsaturated water flow, has been implemented. Modelling results confirm the suitability of the SWMS_2D model to properly describe the hydrologic response of the green roofs. The model adequately reproduces the hydrographs; furthermore, the predicted soil water content profile generally matches the observed values along a vertical profile where measurements are available. 相似文献