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2.
Behavioral, cardiovascular, and self-report measures of cognitive and affective responses to 2 interpersonal challenges were examined among 20 men with a positive (FH+) and 20 with a negative (FH–) family history of hypertension. Heart rate (HR) and blood pressure (BP) were measured throughout the laboratory session; Ss were requested to self-report positive and negative conditions, state anger, and state anxiety that occurred during interactions with a male and female confederate. Behavioral responses to interpersonal tasks were videotaped, coded, and categorized into 4 major groupings (positive verbal, positive nonverbal, negative verbal, and negative nonverbal). FH+ individuals exhibited significantly higher resting HR and systolic BP reactivity to both interactions than FH– counterparts. Analyses of behavioral responses for both interactions revealed significantly more negative verbal and nonverbal behavior and less positive nonverbal behavior among FH+ as compared with FH– Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
The effect of numerical aperture on the fringe spacing in interferometry is analyzed by the use of wave optics. The results are compared with published experimental results, and the influence of apodization of the wave front is discussed. The effects of central obscuration and surface tilt are also considered. 相似文献
4.
Mikels Joseph A.; Larkin Gregory R.; Reuter-Lorenz Patricia A.; Cartensen Laura L. 《Canadian Metallurgical Quarterly》2005,20(4):542
Working memory mediates the short-term maintenance of information. Virtually all empirical research on working memory involves investigations of working memory for verbal and visual information. Whereas aging is typically associated with a deficit in working memory for these types of information, recent findings suggestive of relatively well-preserved long-term memory for emotional information in older adults raise questions about working memory for emotional material. This study examined age differences in working memory for emotional versus visual information. Findings demonstrate that, despite an age-related deficit for the latter, working memory for emotion was unimpaired. Further, older adults exhibited superior performance on positive relative to negative emotion trials, whereas their younger counterparts exhibited the opposite pattern. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
We fed young male Sprague-Dawley rats for 4 wk ad libitum liquid diets containing 34% of the calories as ethanol and 35% as
fat with (AA+) and without (AA−) arachidonic acid (20∶4). Additional rats in the control groups were fed similar diets made
isocaloric with dextrose with (CA+) and without (CA−) 20∶4. The liver triglyceride (TG) content of rats in the AA+ group was
reduced ca. 3-fold over that of rats in the AA-group. The diet consumption and body wts of rats in the AA+ group were significantly
greater than those of rats fed alcohol without the 20∶4 supplement (AA−). Also livers from rats in the AA+ group were as large
as those from rats in control groups (CA+, CA−) and ca. twice as large as those from rats in the AA-group. The fatty acid
composition of liver TG in rats fed the alcohol diet was similar to that of dietary fat. Levels of 20∶4 and docosatetraenoic
acid (22∶4) in liver TG fatty acids from rats fed diets without arachidonate (AA−, CA−) were low (trace to 1.6%). After ingestion
of arachidonic acid, 20∶4 increased to ca. 10% and 22∶4 to ca. 5%. The content of liver phospholipids was higher in livers
of rats fed ethanol (AA−) than in those of controls (CA−).
Presented at the ISF/AOCS World Congress, April 27-May 1, 1980, New York City. 相似文献
6.
The authors define ordered subset processing for standard algorithms (such as expectation maximization, EM) for image restoration from projections. Ordered subsets methods group projection data into an ordered sequence of subsets (or blocks). An iteration of ordered subsets EM is defined as a single pass through all the subsets, in each subset using the current estimate to initialize application of EM with that data subset. This approach is similar in concept to block-Kaczmarz methods introduced by Eggermont et al. (1981) for iterative reconstruction. Simultaneous iterative reconstruction (SIRT) and multiplicative algebraic reconstruction (MART) techniques are well known special cases. Ordered subsets EM (OS-EM) provides a restoration imposing a natural positivity condition and with close links to the EM algorithm. OS-EM is applicable in both single photon (SPECT) and positron emission tomography (PET). In simulation studies in SPECT, the OS-EM algorithm provides an order-of-magnitude acceleration over EM, with restoration quality maintained. 相似文献
7.
Using the metaphor of viewing a movie premiere, characteristics of doctoral programs in clinical health psychology are outlined. Common elements of training include: uniform training competencies, graduated sequence of training, emphasis upon broad and general training, reliance on the biopsychosocial model, and integration of scientific and practical competencies. Exclusive programs, in which all students are being trained in one area of concentration, are differentiated from programs embedded within general training in clinical or counseling psychology. Elucidation of these program characteristics assists prospective students, faculty members who develop these programs, and those developing educational and training guidelines within clinical health psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
MK Larkin K Holder C Yost E Giniger H Ruohola-Baker 《Canadian Metallurgical Quarterly》1996,122(11):3639-3650
During early development, there are numerous instances where a bipotent progenitor divides to give rise to two progeny cells with different fates. The Notch gene of Drosophila and its homologues in other metazoans have been implicated in many of these cell fate decisions. It has been argued that the role of Notch in such instances may be to maintain cells in a precursor state susceptible to specific differentiating signals. This has been difficult to prove, however, due to a lack of definitive markers for precursor identity. We here perform molecular and morphological analyses of the roles of Notch in ovarian follicle cells during Drosophila oogenesis. These studies show directly that constitutively active Notch arrests cells at a precursor stage, while the loss of Notch function eliminates this stage. Expression of moderate levels of activated Notch leads to partial transformation of cell fates, as found in other systems, and we show that this milder phenotype correlates with a prolonged, but still transient, precursor stage. We also find that expression of constitutively active Notch in follicle cells at later stages leads to a defect in the anterior-posterior axis of the oocyte. 相似文献
9.
Integrating-type time-temperature indicators (TTIs) may be utilized to warn food processors and consumers about storage conditions that may have rendered a food potentially hazardous. As an example of how integrated TTIs could be manufactured to emulate an infinite set of time-temperature situations, a set of conditions which have supported C. botulinum growth and toxin production was compiled. The time-temperature curve representing conservative times required for toxin formation was constructed with data from literature relating to toxin formation as a function of temperature in any media or food product. This set of critical time-temperature data is fit by a conservative empirical relationship that can be used to predict combinations of incubation times and storage temperatures that represent a potential health risk from C. botulinum in foods. A TTI could be constructed to indicate deviation from such a given set of conditions to bring attention to foods that may have been exposed to potentially hazardous temperatures with respect to C. botulinum toxin formation. 相似文献
10.