Throughout vertebrate phylogeny, testosterone has motivated animals to obtain and maintain social dominance-a fact suggesting that unconscious primordial brain mechanisms are involved in social dominance. In humans, however, the prevailing view is that the neocortex is in control of primordial drives, and testosterone is thought to promote social dominance via conscious feelings of superiority, indefatigability, strength, and anger. Here we show that testosterone administration in humans prolongs dominant staring into the eyes of threatening faces that are viewed outside of awareness, without affecting consciously experienced feelings. These findings reveal that testosterone motivates social dominance in humans in much the same ways that it does in other vertebrates: involuntarily, automatically, and unconsciously.

When in pursuit of rewards, humans weigh the value of potential rewards against the amount of effort that is required to attain them. Although previous research has generally conceptualized this process as a deliberate calculation, recent work suggests that rudimentary mechanisms-operating without conscious intervention-play an important role as well. In this article, we propose that humans can perform a basic integration of reward value and effort requirements without conscious awareness. Furthermore, we propose that conscious awareness of rewards allows for the use of more advanced functions in reward pursuit, which consider the specific course of action that leads to reward attainment. Using a monetary reward priming paradigm that allows us to dissect the performance effects of rewards (i.e., coins of different value) into conscious and unconscious components, we tested this proposal in 3 experiments. Overall, results indicate that people rely on a simple yet adaptive mechanism that unconsciously conserves effort during reward pursuit, because it makes people more reward sensitive whenever more effort is required of the body. Moreover, consciousness supports a more sophisticated mode of reward pursuit, via which people can strategically conserve effort even further. We discuss these findings in the context of decision making, motivation, and consciousness.(PsycINFO Database Record (c) 2012 APA, all rights reserved).

Affect misattribution occurs when affective cues color subsequent unrelated evaluations. Research suggests that affect misattribution decreases when one is aware that affective cues are unrelated to the evaluation at hand. We propose that affect misattribution may even occur when one is aware that affective cues are irrelevant, as long as the source of these cues seems ambiguous. When source ambiguity exists, affective cues may freely influence upcoming unrelated evaluations. We examined this using an adapted affect misattribution procedure where pleasant and unpleasant responses served as affective cues that could influence later evaluations of unrelated targets. These affective cues were either perceived as reflecting a single source (i.e., a subliminal affective picture in Experiment 1; one's internal affective state in Experiment 2), or as reflecting two sources (i.e., both) suggesting source ambiguity. Results show that misattribution of affect decreased when participants perceived affective cues as representing one source rather than two.

The gaze of a fearful face silently signals a potential threat's location, while the happy-gaze communicates the location of impending reward. Imitating such gaze-shifts is an automatic form of social interaction that promotes survival of individual and group. Evidence from gaze-cueing studies suggests that covert allocation of attention to another individual's gaze-direction is facilitated when threat is communicated and further enhanced by trait anxiety. We used novel eye-tracking techniques to assess whether dynamic fearful and happy facial expressions actually facilitate automatic gaze-imitation. We show that this actual gaze-imitation effect is stronger when threat is signaled, but not further enhanced by trait anxiety. Instead, trait anger predicts facilitated gaze-imitation to reward, and to reward compared to threat. These results agree with an increasing body of evidence on trait anger sensitivity to reward.

Rivalry for dominance is a recurrent challenge in human social interaction. During these social dominance interactions, some people rapidly break eye contact, whereas others merely try to avoid such eye-to-eye confrontations. The first is an example of submissive gaze aversion, whereas the second reflects anxious gaze avoidance. We tested these distinct forms of gaze behavior within a social-memory setting and show that anxious individuals vigilantly attend to, superiorly remember, and subsequently avoid social threats (i.e., angry faces). Furthermore, submissive individuals, as indexed by high trait anxiety and low trait anger, exhibit rapid gaze aversion from facial anger. Mechanisms of hypervigilance-avoidance thus seem to underlie natural gaze behavior and enhanced memory for threat in anxiety. Accordingly, we propose the term hypercoding-avoidance, which describes how anxious individuals habitually scan their immediate social environment for threat, remember its location, and subsequently avoid it. Moreover, this is the first experimental evidence showing that submissive gaze aversion is distinct from anxious gaze avoidance.(PsycINFO Database Record (c) 2012 APA, all rights reserved).

The frequency Escherichia coli O157 genotypes among bovine, food and human clinical isolates from The Netherlands was studied. Genotyping included the lineage-specific polymorphism assay (LSPA6), the Shiga-toxin-encoding bacteriophage insertion site assay (SBI), and PCR detection and/or subtyping of virulence factors and markers (stx1, stx2a/stx2c, q21/Q933, tir255A>T, rhsA 3468C>G). LSPA6 lineage II dominated among bovine isolates (63%) followed by lineage I/II (35.6%) and lineage I (1.4%). In contrast, the majority of the human isolates were typed as lineage I/II (77.6%), followed by lineage I (14.1%) and lineage II (8.2%). Multivariate analysis revealed that the tir255A>T SNP and the stx2a/stx2c gene variants were the genetic features most differentiating human from bovine isolates. Bovine and food isolates were dominated by stx2c (86.4% and 65.5%, respectively). Among human isolates the frequency of stx2c was 36.5% while the frequency of stx2a and stx2a+stx2c 41.2% and 22.4% respectively. Bovine isolates showed equal distribution of tir255A (54.8%) and tir255T (45.2%) while human isolates were dominated by the tir255T genotype (92.9%). LSPA6 lineage I isolates were all genotype stx2c and tir255T, while LSPA6 lineage II was dominated by tir255A (86.4%) and stx2c (90.9%). LSPA6 lineage I/II isolates were all genotype tir255T but showed more variation in stx2 types. The results support the hypothesis that in The Netherlands the genotypes primarily associated with human disease form a minor subpopulation in the bovine reservoir. Comparison with published data revealed that the distribution of LSPA6 lineages among bovine and human clinical isolates differs considerably between The Netherlands and North-America.

We examined whether exposure to cues of attractive food reduces effortful behavior toward healthy foods for restrained eaters. After manipulating food pre-exposure, we recorded handgrip force while presenting participants with pictures of healthy food objects. Because participants were led to expect that they could obtain each object (not specified beforehand) by squeezing the handgrip as forcefully as possible while the object was displayed on the screen, the recorded handgrip force constitutes a measure of spontaneous effortful behavior. Results show that restrained eaters, but not unrestrained eaters, displayed less forceful action toward healthy food objects (i.e., lower exertion of force) when pre-exposed to tempting food cues. No effects were found on palatability perceptions of the healthy foods. The results provide further insight into why restrained eaters have difficulties in maintaining a low-calorie diet in food-rich environments.

Pork contributes significantly to the public health disease burden caused by Salmonella infections. During the slaughter process pig carcasses can become contaminated with Salmonella. Contamination at the slaughter-line is initiated by pigs carrying Salmonella on their skin or in their faeces. Another contamination route could be resident flora present on the slaughter equipment. To unravel the contribution of these two potential sources of Salmonella a quantitative study was conducted. Process equipment (belly openers and carcass splitters), faeces and carcasses (skin and cutting surfaces) along the slaughter-line were sampled at 11 sampling days spanning a period of 4months. Most samples taken directly after killing were positive for Salmonella. On 96.6% of the skin samples Salmonella was identified, whereas a lower number of animals tested positive in their rectum (62.5%). The prevalence of Salmonella clearly declined on the carcasses at the re-work station, either on the cut section or on the skin of the carcass or both (35.9%). Throughout the sampling period of the slaughter-line the total number of Salmonella per animal was almost 2log lower at the re-work station in comparison to directly after slaughter. Seven different serovars were identified during the study with S. Derby (41%) and S. Typhimurium (29%) as the most prominent types. A recurring S. Rissen contamination of one of the carcass splitters indicated the presence of an endemic 'house flora' in the slaughterhouse studied. On many instances several serotypes per individual sample were found. The enumeration of Salmonella and the genotyping data gave unique insight in the dynamics of transmission of this pathogen in a slaughter-line. The data of the presented study support the hypothesis that resident flora on slaughter equipment was a relevant source for contamination of pork.

The conscious awareness of voluntary action is associated with systematic changes in time perception: The interval between actions and outcomes is experienced as compressed in time. Although this temporal binding is thought to result from voluntary movement and provides a window to the sense of agency, recent studies challenge this idea by demonstrating binding in involuntary movement. We offer a potential account for these findings by proposing that binding between involuntary actions and effects can occur when self-causation is implied. Participants made temporal judgements concerning a key press and a tone, while they learned to consider themselves as the cause of the effect or not. Results showed that implied self-causation (vs. no implied self-causation) increased temporal binding. Since intrinsic motor cues of movement were absent, these results suggest that sensory evidence about the key press caused binding in retrospect and in line with the participant's sense of being an agent.

In this review an overview is given on antibiotic resistance (AR) mechanisms with special attentions to the AR genes described so far preceded by a short introduction on the discovery and mode of action of the different classes of antibiotics. As this review is only dealing with acquired resistance, attention is also paid to mobile genetic elements such as plasmids, transposons, and integrons, which are associated with AR genes, and involved in the dispersal of antimicrobial determinants between different bacteria.