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71.
This paper deals with the application of a performance-based approach on the durability of concrete made with an Algerian natural pozzolan. The evaluation of the durability of concrete was based on the comparison of durability indicators with a reference concrete usually found in Algeria. The properties measured included general indicators (water porosity, gas permeability, capillary absorption and Portlandite content) and specific indicators related to degradation phenomena that might occur in Algeria: corrosion induced by carbonation and chlorides, and chemical attacks by sulphates and acids. For the specific degradations, the indicators measured included carbonation depths, chloride diffusion coefficients, chloride permeability, expansion and sulphate profiles, and depth of leaching due to ammonium nitrate attack. The results showed that general durability indicators were almost equivalent for all the types of concrete tested, highlighting the importance of using specific indicators for each type of exposure. The results of specific indicators for corrosion and acid attacks showed that increasing the pozzolan content led to higher resistance of the concrete. Thus, it is possible to improve the durability of typical concretes currently made in Algeria by using local materials. 相似文献
72.
Gailliot Matthew T.; Baumeister Roy F.; DeWall C. Nathan; Maner Jon K.; Plant E. Ashby; Tice Dianne M.; Brewer Lauren E.; Schmeichel Brandon J. 《Canadian Metallurgical Quarterly》2007,92(2):325
The present work suggests that self-control relies on glucose as a limited energy source. Laboratory tests of self-control (i.e., the Stroop task, thought suppression, emotion regulation, attention control) and of social behaviors (i.e., helping behavior, coping with thoughts of death, stifling prejudice during an interracial interaction) showed that (a) acts of self-control reduced blood glucose levels, (b) low levels of blood glucose after an initial self-control task predicted poor performance on a subsequent self-control task, and (c) initial acts of self-control impaired performance on subsequent self-control tasks, but consuming a glucose drink eliminated these impairments. Self-control requires a certain amount of glucose to operate unimpaired. A single act of self-control causes glucose to drop below optimal levels, thereby impairing subsequent attempts at self-control. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
73.
The main purpose of this study is to evaluate the moderating effect of conjugal violence on the relationship between Dependency, Self-Criticism and depression. It investigates whether the contribution of personality to the severity of depressive symptoms diminishes as conjugal violence reported by women increases. Participants (N = 151) completed the Depressive Experiences Questionnaire, the Conflict Tactics Scales - II and two measures of depressive symptoms. The results of hierarchical hierarchical regression analyses, including quadratic interactions, indicate different patterns for each of the two personality dimensions. The main hypothesis is confirmed for Dependency: Dependency is related to the severity of depressive symptoms when violence is "moderate." However, the strength of this relationship diminishes as violence increases, the severity of the traumatic situation taking precedence over personal dispositions. On the other hand, results indicate that Self-Criticism adds up to the impact of conjugal violence on depressive symptoms. The discussion underlines the importance of integrating individual factors in the study of depression in women with a history of conjugal violence. It also underlines implications for the operationalisation of negative events likely to generate depressive affect in Dependent and Self-Critical individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
A discrete-trials procedure was used to measure 6 homing pigeons' ability to discriminate one (fixed) stimulus duration from another (variable) temporal stimulus composed of 12 different durations, ranging from 2.5 to 57.5 sec, with an arithmetic mean of 30 sec. Exposed to a 3-key array, Ss were trained to peck the left key when the center key had been lit for the fixed duration and to peck the right key when the center key had been lit for intervals from the variable-duration set. Across 11 experimental conditions, the fixed duration was varied nonsystematically from 5 to 55 sec in steps of 5 sec. The same set of variable durations was used in each condition. Contrary to a scalar timing model, the indifference point between the fixed and variable durations was not a linear function of the fixed duration. Further, discriminability of the fixed from the variable durations was not symmetric about the arithmetic mean of the variable durations, and response bias was systematically related to the fixed duration. It is concluded that animals' ability to discriminate temporal stimuli is not independent of their response biases when 1 temporal stimulus is made up of a number of different temporal components. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Carobene Genevieve; Cyr Francine; Cyr-Villeneuve Catherine; Bergeron éliane 《Canadian Metallurgical Quarterly》2009,41(2):67
There exists an abundant literature on the effects of parental separation on children. However, few studies focus on the coping process employed by children to help them deal with this familial restructuring. Eighty-five children and their parents, from intact or separated families, answered questionnaires measuring parental conflicts, the child’s coping process, and the child’s adaptation to validate a theoretical model of child adaptation and to identify the mechanisms by which this process is related to their adaptation. The model takes into account the coping process of children subjected to family-related stress. Path analyses show that threat appraisal influences the choice of coping strategies, and reveal that active strategies influence the perceived efficacy of the coping strategies. The results also show that the children’s coping process is partially tied to their adaptation in various ways. However, avoidance and support seeking coping strategies could have different impacts on the adaptation of the children of each group. This study also draws attention to the direct impact of conjugal conflicts on the child’s adaptation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Chambless Dianne L.; Caputo G. Craig; Bright Priscilla; Gallagher Richard 《Canadian Metallurgical Quarterly》1984,52(6):1090
Describes the development of the Agoraphobic Cognitions Questionnaire and the Body Sensations Questionnaire, companion measures for assessing aspects of fear of fear (panic attacks) in agoraphobics. The instruments were administered to 175 agoraphobics (mean age 37.64 yrs) and 43 controls (mean age 36.13 yrs) who were similar in sex and marital status to experimental Ss. Results show that the instruments were reliable and fared well on tests of discriminant and construct validity. It is concluded that these questionnaires are useful, inexpensive, and easily scored measures for clinical and research applications and fill a need for valid assessment of this dimension of agoraphobia. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
To determine whether the clinical adverse interactions of terfenadine with azole antifungals and macrolide antibiotics may be related to inhibition of terfenadine biotransformation, an in vitro system was developed to follow the metabolism of terfenadine by rat liver S9 or human liver microsomes. When test compounds were coincubated with terfenadine, the metabolites formed and unchanged terfenadine was quantitatively analyzed by HPLC. Five metabolites of terfenadine were formed by rat liver S9: predominantly alcohol metabolite (III), with four minor metabolites--azacyclonol (I), acid metabolite (II), an unidentified metabolite (IV), and a new ketone metabolite (V). By human liver microsomes, two major metabolites were formed: azacyclonol (I) and alcohol metabolite (III). Ketoconazole, fluconazole, itraconazole, erythromycin, clarithromycin, and troleandomycin potently inhibited terfenadine metabolism by human liver (IC50 = 4-10 microM), but inhibition by rat liver was weaker (IC50 = 87-218 microM) and 18% maximally for troleandomycin. Other CYP3A substrates (cyclosporin A, naringenin, and midazolam) also demonstrated potent inhibition of terfenadine biotransformation in human liver microsomes (IC50 = 17-24 microM). Substrates of other P450 families [sparteine (CYP2D6), caffeine (CYP1A), and diclofenac (CYP2C)] only very weakly inhibited terfenadine metabolism. Dixon plot analyses for human liver revealed competitive/reversible inhibition by the azole antifungals and macrolide antibiotics of azacyclonol and alcohol metabolite formations.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
Dianne Berry
Anna Hart
《Expert systems with applications》1991,2(4):245-250In recent years there has been a growing debate over whether or not standards should be produced for user system interfaces. Those in favor of standardization argue that standards in this area will result in more usable systems, while those against argue that standardization is neither practical nor desirable. The present paper reviews both sides of this debate in relation to expert systems. It argues that in many areas guidelines are more appropriate than standards for user interface design. 相似文献
79.
The literature on patient demographic and clinical characteristics as predictors of length of psychiatric hospital stay suggests that investigators have been unsuccessful in producing a prediction model using this information to account for any substantial criterion variance. The present study maximized predictions of length of hospital stay by using a more powerful statistical procedure and an expanded number of predictor variables. Data were obtained on 877 patients who were discharged from psychiatric hospitals in 1980. Results show that despite these improvements, the resulting proportion of variance was moderate at best. It is concluded that increases in similar information are unlikely to improve predictions. The use of untapped variables (e.g., management philosophies and politically based information) is discussed. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
We describe the second example of a duodenal-caval fistula in a patient with peptic ulcer disease. This condition was complicated by embolization of intestinal contents to the lung, with abundant intravascular mucin. This is the first histological documentation of intravascular mucin apart from amniotic fluid embolism. It is well known that mucin may activate coagulation. We propose that intravascular mucin activated the coagulation cascade in our patient, causing disseminated intravascular coagulation and adult respiratory distress syndrome. 相似文献