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Objective: We experimentally tested the degree that the size-weight illusion depends on perceptual conditions allowing the observer to assume that both the visual and the kinesthetic stimuli of a weight seen and lifted emanate from the same object. We expected that the degree of the illusion depended on the "realism" provided by different kinds of virtual reality (VR) used when the weights are seen in virtual reality and at the same time lifted in natural reality.Background: Welch and Warren (1980) reported that an intermodal influence can be expected only if perceptual information of different modalities is compellingly related to only one object.Method: Objects of different sizes and weights were presented to 50 participants in natural reality or in four virtual realities: two immersive head-mounted display VRs (with or without head tracking) and two nonimmersive desktop VRs (with or without screening from input of the natural environment using a visor). The objects' heaviness was scaled using the magnitude estimation method.Results: Data show that the degree of the illusion is largest in immersive and lowest in nonimmersive virtual realities.Conclusion: The higher the degree of the illusion is, the more compelling the situation is perceived and the more the observed data are in correspondence with the data predicted for the illusion in natural reality. This shows that the kind of mediating technology used strongly influences the presence experienced.Application: The size-weight illusion's sensitivity to conditions that affect the sense of presence makes it a promising objective presence measure. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examine emotional reactions and empathy towards robots and humans using fMRI. [•] Overall HHI and HRI elicit similar neural activation patterns in limbic structures. [•] Abusive HHI results in more neural activation than abusive HRI. [•] Self-report findings regarding participant’s emotional states support fMRI results. [Copyright &y& Elsevier]

Stress and additional load on the executive system, produced by a parallel working memory task, impair decision making under risk. However, the combination of stress and a parallel task seems to preserve the decision-making performance [e.g., operationalized by the Game of Dice Task (GDT)] from decreasing, probably by a switch from serial to parallel processing. The question remains how the brain manages such demanding decision-making situations. The current study used a 7-tesla magnetic resonance imaging (MRI) system in order to investigate the underlying neural correlates of the interaction between stress (induced by the Trier Social Stress Test), risky decision making (GDT), and a parallel executive task (2-back task) to get a better understanding of those behavioral findings. The results show that on a behavioral level, stressed participants did not show significant differences in task performance. Interestingly, when comparing the stress group (SG) with the control group, the SG showed a greater increase in neural activation in the anterior prefrontal cortex when performing the 2-back task simultaneously with the GDT than when performing each task alone. This brain area is associated with parallel processing. Thus, the results may suggest that in stressful dual-tasking situations, where a decision has to be made when in parallel working memory is demanded, a stronger activation of a brain area associated with parallel processing takes place. The findings are in line with the idea that stress seems to trigger a switch from serial to parallel processing in demanding dual-tasking situations. [ABSTRACT FROM AUTHOR]

Abstract: Food labeling is the major health policy strategy to counter rising obesity rates. Based on traditional economic theory, such strategies assume that detailed nutritional information will necessarily help individuals make better, healthier choices. However, in contrast to the well-known utility of labels in food marketing, evidence for the efficacy of nutritional labeling is mixed. Psychological and behavioral economic theories suggest that successful marketing strategies activate automatic decision biases and emotions, which involve implicit emotional brain systems. Accordingly, simple, intuitive food labels that engage these neural systems could represent a promising approach for promoting healthier choices. Here we used functional MRI to investigate this possibility. Healthy, mildly hungry subjects performed a food evaluation task and a food choice task. The main experimental manipulation was to pair identical foods with simple labels that emphasized either taste benefits or health-related food properties. We found that such labels biased food evaluations in the amygdala, a core emotional brain system. When labels biased the amygdala's evaluations towards health-related food properties, the strength of this bias predicted behavioral shifts towards healthier choices. At the time of decision-making, amygdala activity encoded key decision variables, potentially reflecting active amygdala participation in food choice. Our findings underscore the potential utility of food labeling in health policy and indicate a principal role for emotional brain systems when labels guide food choices. [Copyright &y& Elsevier]

Glucose repression in the yeast Saccharomyces cerevisiae designates a global regulatory system controlling the expression of various sets of genes required for the utilization of alternate carbon sources. In a screen, designed for the selection of mutants with reduced glycolytic flux we obtained isolates which were shown by complementation of the cloned wild-type gene to be allelic to the glucose repression mutants grr1/cat80/cot2 previously described. We demonstrate that the grr1 lesion lead to a concentration-dependent decrease in glycolytic flux on glucose. It is very likely that this is caused by a significant decrease in the expression of various genes encoding hexose transporters (HXT1,3) leading to a reduced glucose-uptake rate. In contrast, expression of the maltose permease gene (MAL11) and maltose utilization is normal. There is indirect evidence that grr1 affects the uptake of amino acids, and others have shown that the sugar-induced transport of divalent cations is impaired, These effects are not glucose-specific. We suggest that Grr1, a putative cytoplasmic protein, has a central function in the sensing of nutritional conditions for a variety of unrelated substances, and that relief from glucose repression may be a corollary of this defect in sensing. [ABSTRACT FROM AUTHOR]

Reports on the characterization of a glucose-repressed pyruvate kinase isoenzyme Saccharomyces cerevisiae. Subjection of the gene expression to glucose repression; Contentions that the pyruvate kinase may be used under conditions of very low glycolytic flux; Effects of the gene overexpression on the glucose of a pyruvate kinase mutant strain.

Friction between a viscoelastic material and a rough surface occurs in many technical applications, e. g. windshield wiper, rubber gaskets or the tire‐road contact. For the investigation of friction phenomena a detailed frictional contact model is necessary. The friction of viscoelastic materials is divided into the two main effects hysteresis friction and adhesion friction. Multiple influence factors on the friction behaviour are known, e. g. material properties of the contact partners, normal force, excitation frequency through the counterpart, as well as temperature. Due to the frictional forces a system is significantly influenced in its vibrational properties. For the simulation of the complex friction processes with viscoelastic materials, a two‐dimensional friction contact model with the assumption of an isotropic roughness has been developed. The model consists of a rough rigid and a rough viscoelastic layer. The rough rigid layer represents a measured roughness profile. Due to the low stiffness of the viscoelastic material, the counter body can be assumed to be rigid. The viscoelastic layer consists of a number of point‐masses with generalised Maxwell‐models and represents the viscoelastic material. By this model the normal and tangential contact can be simulated dynamically. Effects such as changing the contact status during the friction process are taken into account. A stiffening of the viscoelastic material and thus a lower real contact surface at higher excitation frequencies or low temperatures can be shown with the model. This is especially important for the calculation of adhesion friction, as it depends directly on the actual contact area. [ABSTRACT FROM AUTHOR]

Examines the role of HTR1 gene in the glucose uptake of Saccharomyces cerevisiae. Identification of the dominant HTR1 allele; Determination of the DNA sequence of HTR1-23; Deletion of MTH1 gene; Impact of the dominant mutant allele and the mth1 deletion on HXT gene expression.

Background and aims: Cybersex addiction is discussed controversially, while empirical evidence is widely missing. With respect to its mechanisms of development and maintenance Brand et al. (2011) assume that reinforcement due to cybersex should lead to the development of cue-reactivity and craving explaining recurrent cybersex use in the face of growing but neglected negative consequences. To support this hypothesis, two experimental studies were conducted. Methods: In a cue-reactivity paradigm 100 pornographic cues were presented to participants and indicators of sexual arousal and craving were assessed. The first study aimed at identifying predictors of cybersex addiction in a freely recruited sample of 171 heterosexual males. The aim of the second study was to verify the findings of the first study by comparing healthy (n = 25) and problematic (n = 25) cybersex users. Results: The results show that indicators of sexual arousal and craving to Internet pornographic cues predicted tendencies towards cybersex addiction in the first study. Moreover, it was shown that problematic cybersex users report greater sexual arousal and craving reactions resulting from pornographic cue presentation. In both studies, the number and subjective quality of real-life sexual contacts were not associated to cybersex addiction. Discussion: The results support the gratification hypothesis, which assumes reinforcement, learning mechanisms, and craving to be relevant processes in the development and maintenance of cybersex addiction. Poor or unsatisfying sexual real-life contacts cannot sufficiently explain cybersex addiction. Conclusions: Positive reinforcement in terms of gratification plays a major role in cybersex addiction. [ABSTRACT FROM AUTHOR]

Investigates tobacco use of students in Moscow, Russia using a translated version of the United States Centers for Disease and Prevention's Youth Risk Behavior Surveillance (YRBS) survey. Percentage of tobacco users by age; Gender differences in tobacco use; Model of cigarette smoking behavior by adult Muscovites.