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101.
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The intention of this experimental work is to investigate the influence of elevated temperatures of short duration (usually during fires in buildings) on the properties of concrete that affect the measurements by non-destructive methods (rebound hammer and pulse velocity). Relationships between strength of concrete as well as rebound and pulse velocity versus heating temperatures are established. Finally, the above results are evaluated to find the direct relation between non-destructive measurements and strength of concrete exposed to fire. 相似文献
103.
E Eng 《Canadian Metallurgical Quarterly》1977,25(2):164-171
104.
Cloned genomic DNA sequences corresponding to various regions of the human type II procollagen gene were used to analyze the DNA from 78 normal volunteers. Southern hybridization experiments detected polymorphic HindIII, BamHI, and EcoRI sites. The presence of the polymorphic HindIII site results in a 7.0-kilobase (kb) band, and the absence of this site results in a 14.0-kb band. When present, the BamH1 polymorphic site yields a 4.8-kb band, and when absent, yields a 7.2-kb band. The presence of the EcoRI polymorphic site results in a 3.7-kb band, and its absence results in a 7.0-kb band. Each polymorphic site was mapped. Analyses of the data demonstrated that the sites are present in overall gene frequencies of .39 for HindIII, .04 for BamHI, and .02 for EcoRI. Gene frequencies of the polymorphic sites were also studied with respect to race. The polymorphic sites are present in a Hardy-Weinberg distribution in the study population. Study of an extended family demonstrated that the segregation of the HindIII polymorphic site is consistent with Mendelian inheritance. 相似文献
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106.
Objective: To evaluate the utility of the theory of planned behavior (TPB) for explaining and predicting leisure time physical activity (LTPA) in the chronic kidney disease population. Study Design: Prospective correlational design. Participants: Eighty men (n=52) and women (n=28) with chronic kidney disease (mean serum creatinine=310.55 [±148.75] μmol/L). Method: Baseline interview assessing attitude, subjective norm, perceived behavioral control, and intention to engage in LTPA. Telephone interview 1 week later assessing frequency and intensity of LTPA. Results: Perceived behavioral control (β=.69) but not attitude (β=.17) or subjective norm (β=.02) was associated with intention to engage in LTPA. Intention (β=.53) but not perceived behavioral control (β=.18) predicted LTPA. Conclusion: These findings provide partial support for the utility of the TPB for explaining LTPA among people with chronic kidney disease. Additional research is required to determine if targeting perceived behavioral control may be an effective means for increasing LTPA in this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Taylor Steven; Zvolensky Michael J.; Cox Brian J.; Deacon Brett; Heimberg Richard G.; Ledley Deborah Roth; Abramowitz Jonathan S.; Holaway Robert M.; Sandin Bonifacio; Stewart Sherry H.; Coles Meredith; Eng Winnie; Daly Erin S.; Arrindell Willem A.; Bouvard Martine; Cardenas Samuel Jurado 《Canadian Metallurgical Quarterly》2007,19(2):176
Accumulating evidence suggests that anxiety sensitivity (fear of arousal-related sensations) plays an important role in many clinical conditions, particularly anxiety disorders. Research has increasingly focused on how the basic dimensions of anxiety sensitivity are related to various forms of psychopathology. Such work has been hampered because the original measure--the Anxiety Sensitivity Index (ASI)--was not designed to be multidimensional. Subsequently developed multidimensional measures have unstable factor structures or measure only a subset of the most widely replicated factors. Therefore, the authors developed, via factor analysis of responses from U.S. and Canadian nonclinical participants (n = 2,361), an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns. Factorial validity of the ASI-3 was supported by confirmatory factor analyses of 6 replication samples, including nonclinical samples from the United States and Canada, France, Mexico, the Netherlands, and Spain (n = 4,494) and a clinical sample from the United States and Canada (n = 390). The ASI-3 displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
Jyi-Tsong Lin Yi-Chuen Eng 《Electron Devices, IEEE Transactions on》2007,54(12):3238-3244
An original blocking technology is proposed for improving the short-channel characteristics of polycrystalline silicon thin-film transistors (poly-Si TFTs). In particular, two types of modified devices called poly-Si TFT with block oxide and poly-Si on partial insulator (POPI)-TFT are designed for the first time in this field to enhance device performance. The proposed TFT structures can significantly reduce short-channel effects when compared with a thick source/drain (S/D) poly-Si TFT (i.e., the fully depleted TFT). In addition, an ultrathin (UT) S/D structure (UT-TFT) is designed to verify that the block oxide TFT devices do achieve improved performance without needing the thin active layers and ultrashallow junction depth. Also, the POPI-TFT is found to reduce the thermal instability through its natural body-tied scheme. 相似文献
109.
The retrieval of plant biophysical and biochemical properties from high spectral resolution data represents an active area of research within the remote sensing field. Scientific studies in this area are usually supported by computational simulations of light attenuation processes within foliar tissues. In heterogeneous organic materials, like plant leaves, sieve and detour effects can affect these processes and ultimately change the light gradients within these tissues and their spectral signatures. Although these effects have been extensively examined for applications involving the interactions of visible radiation with plant leaves, little is known about their role in the infrared domain. In this paper, we describe the procedural basis for their incorporation in the modeling of infrared-radiation transport (in the range of 750-2500 nm) within plant leaves. We also assess their impact on the predictability of simulation solutions relating the directionality of the incident radiation and the internal arrangement of the tissues to changes on foliar spectral signatures in this domain. Our investigation is grounded by the observations involving the modeled results and quantitative and qualitative data reported in the literature. 相似文献
110.
Reinforced masonry beams under shear load – Proposals for future designs / Bewehrte schubbeanspruchte Mauerwerksbalken – Vorschläge für zukünftige Bemessungen
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This article is written against the backdrop of the work of the European standardisation committees on the amendment of EN 1996‐1‐1 [N 4] which will also exert an influence on the design of reinforced masonry in Germany. This paper focusses on the design approaches of DIN EN 1996‐1‐1 for untensioned reinforced masonry beams under shear load in the ultimate limit state (ULS). Proposals are made to discuss their revision. The contents of E DIN 1053‐3 [N 3] and of the final draft of the guideline ”Flat Lintels” [7] are taken into account. 相似文献