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排序方式: 共有1306条查询结果,搜索用时 15 毫秒
131.
Demonstrated the utility of open-ended measures for assessing intergroup ambivalence. 42 Canadian undergraduates completed open-ended measures of stereotypes (beliefs about characteristics of group members), symbolic beliefs (beliefs that group members promote or threaten cherished values), and emotions, in order to determine their degree of ambivalence toward Native Peoples, French Canadians, Oriental Immigrants, and Canadians. Ss also completed an attitude measure assessing their overall evaluations of the groups. Examination and comparison of these measures revealed findings consistent with the following theoretical expectations: (1) the positive and negative dimensions were not highly negatively correlated, (2) ambivalence toward the groups differed, and (3) ambivalence toward the groups was not highly correlated. Results support the open-ended measure of ambivalence. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
132.
The objective of the present study was to evaluate the interrelationship between the cuticular and postpharyngeal glands' hydrocarbons, both in the individual ant and during its interaction with nestmates. In vivo radiochemical assays were employed to monitor the de novo hydrocarbon biosynthesis from acetate in the ant's body. The newly synthesized hydrocarbons appeared first internally and after 24 hr they accumulated in the postpharyngeal gland and on the cuticular surface. Blocking the possibility of external transfer of hydrocarbons between cuticle and postpharyngeal gland led to a significant decrease of labeled hydrocarbons in the postpharyngeal gland. In addition, during encounters between labeled and unlabeled ants, newly synthesized hydrocarbons were transferred, mainly via trophallaxis, but also by allo-grooming and physical contact. In view of these results, we propose as a model for their dynamics that hydrocarbons are synthesized in tissues associated with the integument. Through self-grooming, there is a constant exchange of hydrocarbons between the cuticular surface and the postpharyngeal gland. Furthermore, in encounters between nestmates, hydrocarbons are exchanged among them mostly by trophallaxis, with the mediation of the postpharyngeal gland. Thus, this gland acts as a pool for mixing colonial hydrocarbons and may serve to attain a unified colony odor. 相似文献
133.
M. Ángeles Pozo-Bayón Inmaculada Andújar-Ortiz M. Victoria Moreno-Arribas 《Food research international (Ottawa, Ont.)》2009,42(7):754-761
In recent years the use of inactive dry yeast (IDY) preparations such as inactive yeast, yeast autolysates, yeast extracts and yeast hulls or walls have been widely used within the oenological industry to improve either technological processes or the sensory characteristics of wines. Some of these preparations have very specific applications and there are currently many of these products in the market under different brands that promise different ways of improving wine characteristics. Nevertheless, scientific information about the chemistry beyond their use and their action mode is still scarce.The objective of this review is to revise the different applications of specific IDY preparations in winemaking, on the basis of their action mechanisms taking into consideration the scientific information available, underlining the necessity of more scientific work in order to better characterize their chemical composition, their action mechanisms, and the establishment of better criteria for their oenological use. 相似文献
134.
Victoria Fernández Azahara Díaz Álvaro Blanco Jesús Val 《Journal of the science of food and agriculture》2009,89(13):2323-2330
BACKGROUND: A strategy to supply Ca directly to fruits as a tool for improving peach quality has been devised and tested under field conditions. Since peaches in the area of study (Calanda, Spain) are routinely bagged shortly after thinning, a method based on the application of Ca gels to the fruit surface was introduced. The effect of surface treatments was assessed in terms of quality, nutrient balance and surface deposition. RESULTS: Application of Ca‐containing formulations increased mesocarp and exocarp Ca concentrations, providing evidence for the penetration of Ca through the peach skin. Surface Ca treatments had a particular mode of deposition and in some instances improved the shelf life of fruits without affecting their quality. CONCLUSION: Surface treatment with Ca‐containing gels appears to be a viable approach to increase fruit Ca, quality and storability of bagged peach cultivars and should be optimised in future studies. Copyright © 2009 Society of Chemical Industry 相似文献
135.
136.
Juraj Doupovec Ilja Thurzo Drahoslav Barančok Victoria P. Shilo 《Materials Research Bulletin》1977,12(2):119-125
When cooling a melt the cooling rate in different layers varies due to differences in heat transfer. These changes in cooling rate were determined experimentally for the As2S3 melt in a quartz ampoule with diameter of 17 mm. The cooling rate at air quenching varies from 1.36 K/s in the bulk middle to 2.11 K/s in the border layers, and from 3.54 to 38.80 K/s for water quenching, respectively. Further, the corresponding changes in the density, microhardness, glass-transition temperature and electrical conductivity in dependence on the choice of the measured sample from various parts of the bulk were found. The anomalous behaviour of these parameters in dependence on the cooling rate corresponds to the polymeric structure of the glass. 相似文献
137.
Carver Charles S.; Pozo Christina; Harris Suzanne D.; Noriega Victoria; Scheier Michael F.; Robinson David S.; Ketcham Alfred S.; Moffat Frederick L. Jr.; Clark Kimberley C. 《Canadian Metallurgical Quarterly》1993,65(2):375
At diagnosis, 59 breast cancer patients reported on their overall optimism about life; 1 day presurgery, 10 days postsurgery, and at 3-, 6-, and 12-mo follow-ups, they reported their recent coping responses and distress levels. Optimism related inversely to distress at each point, even controlling for prior distress. Acceptance, positive reframing, and use of religion were the most common coping reactions; denial and behavioral disengagement were the least common reactions. Acceptance and the use of humor prospectively predicted lower distress; denial and disengagement predicted more distress. Path analyses suggested that several coping reactions played mediating roles in the effect of optimism on distress. Discussion centers on the role of various coping reactions in the process of adjustment, the mechanisms by which dispositional optimism vs pessimism appears to operate, third variable issues, and applied implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
138.
MJ Reardon TD Hedrick GV Letsou HJ Safi R Espada JC Baldwin 《Canadian Metallurgical Quarterly》1997,64(5):1480-1482
Chronic traumatic aneurysm of the thoracic aorta is an unusual occurrence. Previously, arteriography was performed on all patients seen in our institution with this entity to allow confirmation of the diagnosis and anatomic delineation for operation. A case of chronic traumatic aneurysm of the distal descending aorta discovered on a routine chest roentgenogram and evaluated with chest computed tomographic scanning with three-dimensional reconstruction is presented. It is our belief that not all thoracic aneurysms require arteriography, and improved methods of computed tomographic scanning allow adequate diagnosis and anatomic delineation with decreased morbidity and cost. 相似文献
139.
G Acciari J C Eckroad L F Fajardo R Mu?oz R de Mercado A Pradilla G Quintero B de Ramíez F Victoria D H Wilson 《Archivos latinoamericanos de nutrición》1977,27(3):359-375
The main objective of this work is to determine what anthropometric method to use under field conditions, given the kind of mainutrition to be detected. In the first part of the work some criteria and procedures are given by which to compare the field perfomance characteristics (i.e. transportability, facility of use, etc.), of the most commonly used instruments. Then we extrapolate these characteristics to the respective methods like weight for age, weight for height, height for age, etc. In the second part we present a correlation matrix among the various methods and analyze it in order to associate with each method a specific typology of malnutrition. 相似文献
140.
We have applied an in vitro system that mimics thymic negative selection to investigate signaling pathways that may be important for the removal of autoreactive cells from the thymus. We sought to more precisely determine the contribution of calcium-dependent pathways to CD4+CD8+ thymocyte deletion that is mediated by either an antigenic peptide or a peptide analogue. We show that the requirement for external calcium influx is dependent upon the strength of the deleting ligand. Furthermore, these results correlate well with a requirement, under certain circumstances, for signaling through the calcium/calmodulin-dependent phosphatase calcineurin. The use of suboptimal stimuli may, therefore, be useful in revealing biochemical pathways important for CD4+CD8+ thymocyte negative selection. 相似文献