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91.
This meta-analysis of studies of the persuasive impact of fear appeals evaluated the contribution of our stage model of the processing of fear-arousing communications relative to other fear appeal theories. In contrast to other theories, our stage model (a) specifies the cognitive processes underlying persuasion through fear-arousing communications, (b) proposes that threat-induced defensive processing does not interfere with the effectiveness of fear-arousing communications but actually contributes to it, and (c) predicts that vulnerability and severity manipulations have differential effects on measures of attitude as compared with intention and behavior. To evaluate these predictions, the authors expanded on previous meta-analyses by assessing the independent as well as joint effects of vulnerability to and severity of a risk, both on information processing and on measures of persuasion (attitude, intention, behavior). Overall, findings were consistent with the stage model. The theoretical and practical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
The aim of this paper is to formulate a framework for studying dynamical properties of parallel computation processes represented by a continuous map acting on a space of infinite real traces. The fundamental concept of our approach is to join the tools of symbolic dynamics and trace theory. Research of the second author was partly supported by an annual national scholarship for young scientists from the Foundation for Polish Science and AGH grant No. 10.420.03. Both authors were supported by the Polish Ministry of Science and Higher Education, grant N206 027 32/4270.  相似文献   
93.
The design and performance of a 12-b charge redistribution analog-to-digital converter (ADC) is described. The architecture is chosen to minimize power dissipation. Die area is minimized by a modified self-calibration algorithm and nonvolatile memory based on polysilicon fuses. The ADC is fabricated in a 1-μm CMOS process. It converts at a 200-kHz rate with a power dissipation of 10 mW  相似文献   
94.
We investigated the reconstitutive potential of haematopoietic progenitor cells collected in autologous whole blood during multicycle dose-intensified chemotherapy. Forty patients with metastatic solid tumours were treated with up to six cycles of cisplatin and escalating doses of ifosfamide every 14 days. Cisplatin was administered in 3% sodium chloride over 3 h, followed by ifosfamide over 24 h and mesna over 36 h. The first cohort of patients received granulocyte colony-stimulating factor (G-CSF) days 4-14. Once dose-limiting toxicity was reached in cohort 1, the study continued with a second cohort of patients, in whom, in addition to G-CSF on days 4-14, 500 ml of G-CSF and chemotherapy-'primed' whole blood was collected on day 15, i.e. on day 1 of treatment cycles two to six, before cisplatin administration. This volume of blood was kept unprocessed at 4 degrees C and reinfused 20-24 h after the completion of ifosfamide. In cohort 1, dose-limiting toxicity (DLT) was reached at ifosfamide 6.0 g m(-2) with two out of six of the patients developing neutropenic fever. Although in cohort 2 no neutropenic fever was encountered, neither the frequency nor the duration of grade 4 neutropenia and thrombocytopenia were reduced. Cumulative asthenia resulted in DLT at 7.0 g m(-2). The median number of CD34+ cells in 500 ml of whole blood after the first cycle (i.e. at start of cycle 2) was 1.15 x 10(6) kg(-1). This number was significantly greater after the second cycle (2.06 x 10(6) kg(-1), P = 0.01) and then gradually decreased after cycles three to six. After storing whole blood, the number of CD34+ cells had not decreased (median + 10%). We conclude that the method of combined bone marrow support by G-CSF and haematopoietic progenitor cells in autologous whole blood collected before each cycle of a 2-weekly regimen of cisplatin-ifosfamide does not result in clinically measurable reduced bone marrow toxicity compared with what can be expected by the use of G-CSF alone.  相似文献   
95.
96.
Journal of Materials Engineering and Performance - This survey overviews the functional performance of manufactured components produced by typical finishing machining operations in terms of their...  相似文献   
97.

The filling barricade is one of the key components of roadway cemented backfill systems and this research focuses on critical factors influencing the performance of these systems, particularly the lateral stress characteristics and the stability of the filling barricade. In this paper, a theoretical model is presented and applied to obtain and calculate the lateral pressures exerted on the filling barricade and to understand the effects of the filling process. It is found that the yield stress of cemented backfill increases with curing time and this relationship can be described as an increasing power function. The lateral stresses exerted on the filling barricade increase over time during the filling period but decrease over time during the waiting period. Both the maximum lateral stress exerted on the filling barricade and the decreasing amplitude decrease as the number of filling rounds increases. In the calculation case, the maximum lateral stress declines from 0.161 MPa to 0.0148 MPa when the number of filling rounds increases from one to six. From these results, the filling process with three rounds is determined to be the optimal process scheme. In the first round, the lateral stress increases to 0.0369 MPa during the filling period and decreases to 0.0146 MPa during the waiting period; In the second round, the lateral stress increases to 0.0368 MPa then decreases to 0 MPa; in the third round, the lateral stress of the filling barricade stays at 0 MPa.

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98.
The most common accelerated corrosion test used for aluminum brazing sheet is the Sea Water Acidified Accelerated Test (SWAAT). However, still some ambiguity exists, indicating that the test suffers from significant scattering of the results.Keeping the climatic parameters constant, this study elucidates how the variations of the test results are material dependent. Applying a new statistical reliability evaluation and interpretation method, it was shown that the SWAAT test is valid for product performance comparison purposes. Comparing the corrosion mechanism and morphology of attack it was proved that the SWAAT performance of the material can be reflected in potentiodynamic responses.  相似文献   
99.
Photolytic debromination of decabromodiphenyl ether (BDE 209)   总被引:8,自引:0,他引:8  
Polybrominated diphenyl ethers (PBDE) are commonly used flame retardants. During the past years, concerns have increased due to their occurrence in the environment and humans. In general, the concentrations of lower brominated (tetra-penta) diphenyl ethers in biota exceed those of the most heavily used product, decabromodiphenyl ether (DecaBDE). In this study, the photolytic debromination of DecaBDE has been investigated in order to study the formation of lower brominated diphenyl ethers. The time course of photolysis of DecaBDE was studied in toluene, on silica gel, sand, sediment and soil using artificial sunlight and on the natural matrices (sediment, soil, sand) also using natural sunlight. DecaBDE was photolytically labile and formed debromination products in all matrices studied. Nona- to tetraBDEs were formed as well as some PBDFs. The half-lives in toluene and on silica gel were less than 15 min, and half-lives on other matrices ranged between 40 and 200 h. No differences were seen in the debromination pattern of BDE congeners sequentially formed in the different matrices or under different light conditions. However, the debromination rates were strongly dependent on the matrix with longer half-lives on natural matrices than artificial ones.  相似文献   
100.
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