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41.
A design for an inexpensive and reliable olfactometer is presented. The design has several advantages for fMRI and electrophysiology investigators. These advantages include relatively rapid odorant rise times, computer control, multiple odor administration, and no ferrous materials near the subjects. In addition, the device is contamination resistant, and, because the air is neither warmed nor humidified, it is unlikely to become an incubator for bacteria. The olfactometer is constructed of off-the-shelf chromatography parts that require little modification.  相似文献   
42.
Advances in genetic epidemiology have increased understanding of common, polygenic preventable diseases such as type 2 diabetes. As genetic risk testing based on this knowledge moves into clinical practice, we propose that genetic counselors will need to expand their roles and adapt traditional counseling techniques for this new patient set. In this paper, we present a genetic counseling intervention developed for a clinical trial [Genetic Counseling/Lifestyle Change for Diabetes Prevention, ClinicalTrials.gov identifier: NCT01034319] designed to motivate behavioral changes for diabetes prevention. Seventy-two phenotypically high-risk participants received counseling that included their diabetes genetic risk score, general education about diabetes risk factors, and encouragement to participate in a diabetes prevention program. Using two validated genetic counseling scales, participants reported favorable perceived control and satisfaction with the counseling session. Our intervention represents one model for applying traditional genetic counseling principles to risk testing for polygenetic, preventable diseases, such as type 2 diabetes.  相似文献   
43.
According to Mohr and Fassinger (2006), identity is seen as both self-identification and collective identification with values, beliefs, traits or behaviours and attachments. Their Lesbian, Gay, and Bisexual (LGB) multidimensional identity model accounts for important variables regarding the constitution of identities. This model not only accesses numerous dimensions of the lives of LGB individuals, but is also based on a body of research that recognizes how LGB difficulties are caused by societal intolerance and marginalization (Mohr & Fassinger, 2000). The Lesbian, Gay, and Bisexual Identity Scale (LGBIS; Kendra & Mohr, 2008) constitutes an operationalization of this multidimensional model, and the aim of this article is to present its construct validity by analysing its factor structure using a sample of Portuguese lesbian, gay and bisexual participants. Results from exploratory and confirmatory factor analyses, as well as from factor invariance analysis across sub-samples are presented. In a general way, the factor structure obtained in this study follows the original proposal of Kendra and Mohr's (2008) LGBIS. Moreover, scale sensitivity analyses are presented in order to check for eventual differences in the factor structure and/or factor intercorrelations regarding participant gender and sexual orientation. These results are then discussed in the light of LGB identity models.  相似文献   
44.
In three experiments rats were given serial preexposure to two flavor stimuli. In Experiment 1, some animals were given exposure to AX followed by the presentation of BX, a forward schedule; the others were given backward preexposure (BX→AX). Conditioning and test trials with the A element showed that salience or effectiveness of A was better protected in the forward than in the backward condition. Experiments 2 and 3 assessed the relevance of this salience modulation mechanism for perceptual learning. In these experiments, generalization of a conditioned aversion from AX to BX was reduced in the forward (but not in the backward) condition only after prolonged exposure, indicating that the establishment of an inhibitory link from B to A is required for successful discrimination. However, generalization to a novel compound stimulus, NX, was reduced in the forward group both after short and long preexposure, suggesting the existence of salience modulation processes that work in parallel with associative inhibition. These results seem to support the existence of a salience modulation mechanism that seems to be beyond the scope of current theories of perceptual learning.  相似文献   
45.
Gómez CX  Carvajal CC 《Psicothema》2012,24(2):302-309
This paper introduces a summary on how to proceed to conduct a factor analysis when the input data are ipsative. The classical factor analysis procedures cannot be used because the covariance matrix is singular. Additionally, previous research on the optimal conditions to conduct factor analysis for ipsatized data is reviewed, and the results of a simulation study are presented. The study includes conditions of sample size, model complexity, and model specification (correct vs. incorrect). The results suggest that researchers should be careful when factor analyzing ipsatized data, particularly if they suspect that the model is incorrectly specified and includes a smaller number of factors.  相似文献   
46.
Previous research showed that handwriting production is mediated by linguistically oriented processing units such as syllables and graphemes. The goal of this study was to investigate whether French adults also activate another kind of unit that is more related to semantics than phonology, namely morphemes. Experiment 1 revealed that letter duration and inter-letter intervals were longer for suffixed words than for pseudo-suffixed words. These results suggest that the handwriting production system chunks the letter components of the root and suffix into morpheme-sized units. Experiment 2 compared the production of prefixed and pseudo-prefixed words. The results did not yield significant differences. This asymmetry between suffix and prefix processing has also been observed in other linguistic tasks. In suffixed words, the suffix would be processed on-line during the production of the root, in an analytic fashion. Prefixed words, in contrast, seem to be processed without decomposition, as pseudo-affixed words.  相似文献   
47.
Background. Longitudinal studies allow us to identify, which specific maths skills are weak in young children, and whether there is a continuing weakness in these areas throughout their school years. Aims. This 2‐year study investigated whether certain socio‐demographic variables affect early mathematical competency in children aged 5–7 years. Sample. A randomly selected sample of 127 students (64 female; 63 male) participated. At the start of the study, the students were approximately 5 years old (M= 5.2; SD= 0.28; range = 4.5–5.8). Method . The students were assessed using the Early Numeracy Test and then allocated to a high (n= 26), middle (n= 76), or low (n= 25) achievers group. The same children were assessed again with the Early Numeracy Test at 6 and 7 years old, respectively. Eight socio‐demographic characteristics were also evaluated: family model, education of the parent(s), job of the parent(s), number of family members, birth order, number of computers at home, frequency of teacher visits, and hours watching television. Results . Early Numeracy Test scores were more consistent for the high‐achievers group than for the low‐achievers group. Approximately 5.5% of low achievers obtained low scores throughout the study. A link between specific socio‐demographic characteristics and early achievement in mathematics was only found for number of computers at home. Conclusions . The level of mathematical ability among students aged 5–7 years remains relatively stable regardless of the initial level of achievement. However, early screening for mathematics learning disabilities could be useful in helping low‐achieving students overcome learning obstacles.  相似文献   
48.
Generalization gradients have been investigated widely in animal conditioning experiments, but much less so in human predictive learning tasks. Here, we apply the experimental design of a recent study on conditioned fear generalization in humans (Lissek et al., 2008) to a predictive learning task, and examine the effects of a number of relevant procedural parameters drawn from the generalization literature in animal conditioning. Experiment 1 shows that prior discrimination learning and steady-state testing procedures sharpen the gradient; Experiment 2 shows that within-subjects testing of the range of generalization stimuli also sharpens the gradient. In addition, Experiment 2 shows that, in case of very flat initial generalization, an orderly gradient can reveal itself through differential rates of extinction learning. Finally, Experiment 2 also evidenced an orderly gradient of generalization-of-extinction. These results suggest that discrimination processes have an important effect on the generalization of predictive learning in humans, and highlight behavioral analogies between animal conditioning and human predictive learning.  相似文献   
49.
The results of this study are part of an investigation to determine whether the cognitive-emotional process of emotional recognition is deficient as a function of the clinical condition and alexithymia in subjects with somatization. This investigation applied the self-assessment of emotion and used a procedure that minimizes the use of verbal skills and verbal comprehension. The specific goal of this study was to verify whether there were differences in the covariation between alexithymia and self-evaluation of the emotional reaction in clinical and nonclinical subjects. The results of this study highlight the significant differences between clinical and control subjects. There were inverse significant correlations with the affective valence in clinical subjects, whereas in the ratings of the TAS-20 in control subjects, there were direct correlations with activation. In the conclusions, we discuss whether the variability of the results of previous research of the relationship between alexithymia and emotional recognition is a characteristic feature of this relationship or an effect of the different sampling and procedures utilized.  相似文献   
50.
This paper tests the efficacy of an intervention program in virtual format intended to train studying and self-regulation strategies in university students. The aim of this intervention is to promote a series of strategies which allow students to manage their learning processes in a more proficient and autonomous way. The program has been developed in Moodle format and hosted by the Virtual Campus of the University of Oviedo. The present study had a semi-experimental design, included an experimental group (n=167) and a control one (n=206), and used pretest and posttest measures (self-regulated learning strategies' declarative knowledge, self-regulated learning macro-strategy planning-execution-assessment, self-regulated learning strategies on text, surface and deep learning approaches, and academic achievement). Data suggest that the students enrolled in the training program, comparing with students in the control group, showed a significant improvement in their declarative knowledge, general and on text use of learning strategies, increased their deep approach to learning, decreased their use of a surface approach and, in what concerns to academic achievement, statistically significant differences have been found in favour of the experimental group.  相似文献   
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