Solute drag or diffusion processes in a migrating thick interface

Hillert proposed a new solute drag formula applicable not only to the migration of grain boundaries, but also to that of interfaces. Svoboda and co-workers derived an expression for the velocity of a migrating thick interface by applying the principle of maximum dissipation. In this article, it is shown that the expressions for the interface velocity, one obtained from Hillert's solute drag formula, and the other derived from the principle of maximum dissipation, are equal for steady-state conditions.     

The state of order in Fe–Al studied by precession electron diffraction

Precession electron diffraction (PED) has been carried out on a fully ordered Fe–40at.%Al solid solution in order to explore its suitability for determining the state of order. The integrated intensity ratio of a superlattice reflection with respect to a fundamental reflection was measured as a function of the sample thickness and the results are well fitted by dynamical simulations. It is proposed that, in addition to conventional X-ray diffraction, PED may provide access to the state of order at microscopic and nanoscopic scales.     

Hindsight bias in political elections

Two studies on political hindsight bias were conducted on the occasions of the German parliament election in 1998 and the Nordrhein-Westfalen state parliament election in 2000. In both studies, participants predicted the percentage of votes for several political parties and recalled these predictions after the election. The observed hindsight effects were stronger than those found in any prior study on political elections (using percentage of votes as the dependent variable). We argue that the length of the retention interval between original judgement and recollection is mainly responsible for this difference. In our second study, we investigated possible artifacts in political hindsight biases using a control-group design where half of the participants recalled their predictions shortly before or after the election. Hindsight bias was preserved, reinforcing the results of earlier studies with non-control-group designs. Finally, we discuss the possibility that the hindsight experience (in political judgement and in general) actually consists of three different, partly independent components.     

DIFFERENTIAL RESPONSE PATTERNS TO THE CONTROL CONDITION BETWEEN TWO PROCEDURES TO ASSESS SOCIAL REINFORCERS FOR CHILDREN WITH AUTISM

Historically, reinforcer assessment procedures focus primarily on identifying nonsocial reinforcers (e.g., tangibles and edibles). Far less empirical attention has been allocated to the systematic identification of social consequences that function as reinforcers. This discrepancy is problematic given that social consequences are commonly incorporated into behavioral treatment programs without systematic evaluation of their efficacy. In this study, two methodologies (a single operant and a concurrent choice) were used to assess social reinforcers for children with autism. Results highlighted differences in response allocation to the control condition between procedures. Specifically, responding occurred in the control condition of the single‐operant procedure but not in the concurrent‐operant procedure. These differences highlight the need for further evaluation of procedures to assess social reinforcers. Copyright © 2013 John Wiley & Sons, Ltd.     

Monkeys perform as well as apes and humans in a size discrimination task

Whether the cognitive competences of monkeys and apes are rather similar or whether the larger-brained apes outperform monkeys in cognitive experiments is a highly debated topic. Direct comparative analyses are therefore essential to examine similarities and differences among species. We here compared six primate species, including humans, chimpanzees, bonobos, gorillas (great apes), olive baboons, and long-tailed macaques (Old World monkeys) in a task on fine-grained size discrimination. Except for gorillas, subjects of all taxa (i.e. humans, apes, and monkeys) were able to discriminate three-dimensional cubes with a volume difference of only 10 % (i.e. cubes of 50 and 48 mm side length) and performed only slightly worse when the cubes were presented successively. The minimal size discriminated declined further with increasing time delay between presentations of the cubes, highlighting the difficulty to memorize exact size differences. The results suggest that differences in brain size, as a proxy for general cognitive abilities, did not account for variation in performance, but that differential socio-ecological pressures may better explain species differences. Our study highlights the fact that differences in cognitive abilities do not always map neatly onto phylogenetic relationships and that in a number of cognitive experiments monkeys do not fare significantly worse than apes, casting doubt on the assumption that larger brains per se confer an advantage in such kinds of tests.     

In Defence of Backyard Chickens

Suppose that animals have rights. If so, may you go down to your local farm store, buy some chicks, raise them in your backyard, and eat their eggs? You wouldn't think so. But we argue, to the contrary, that you may. Just as there are circumstances in which it's permissible to liberate a slave, even if that means paying into a corrupt system, so there are circumstances in which it's permissible to liberate chickens by buying them. Moreover, we contend that restrictions on freedom of movement can be appropriate for chickens, but not humans, because of the obvious differences between the interests of healthy, adult humans versus those of chickens who have been bred for human use. We also argue that egg consumption is permissible based on the plausible assumption that no one's rights are violated in their consumption, and so while there may sometimes be morally preferable uses for eggs, you do nothing unjust in eating them. If we're right, then the rights view doesn't imply that veganism is obligatory; rather, it implies that the constraints on how we source animal products, though highly demanding, are not so demanding that they can't be met.     

The anaphase promoting complex is required for memory function in mice

Learning and memory processes critically involve the orchestrated regulation of de novo protein synthesis. On the other hand it has become clear that regulated protein degradation also plays a major role in neuronal plasticity and learning behavior. One of the key pathways mediating protein degradation is proteosomal protein destruction. The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase that targets proteins for proteosomal degradation by the 26S proteasome. While the APC/C is essential for cell cycle progression it is also expressed in postmitotic neurons where it has been implicated with axonal outgrowth and neuronal survival. In this study we addressed the role of APC/C in learning and memory function by generating mice that lack the essential subunit APC2 from excitatory neurons of the adult forebrain. Those animals are viable but exhibit a severe impairment in the ability to extinct fear memories, a process critical for the treatment of anxiety diseases such as phobia or post-traumatic stress disorder. Since deregulated protein degradation and APC/C activity has been implicated with neurodegeneration we also analyzed the effect of Apc2 deletion in a mouse model for Alzheimer's disease. In our experimental setting loss of APC2 form principle forebrain neurons did not affect the course of pathology in an Alzheimer's disease mouse model. In conclusion, our data provides genetic evidence that APC/C activity in the adult forebrain is required for cognitive function.     

Adult but not juvenile Barbary macaques spontaneously recognize group members from pictures

For group-living animals, it is crucial to distinguish one’s own group members from those of other groups. Studies applying operant conditioning revealed that monkeys living in relatively small groups are able to recognize their own group members when tested with photographs of group members and other conspecifics. Employing a simple looking time paradigm, we here show that Barbary macaques living in two social groups comprising 46 and 57 individuals, respectively, at the enclosure ‘La Forêt des Singes’ at Rocamadour are able to spontaneously distinguish photographs of members of their own group from those depicting animals that belong to another group. This ability appears to develop with age, as juveniles did not discriminate between members of their own group and another group, although they showed generally more interest in the pictures than did adults. Juveniles frequently displayed picture directed behaviours such as lip-smacking, touching and sniffing in both conditions, indicating that the stimuli were highly salient to them. In conclusion, it appears that at least adult monkeys are able to memorize the faces of a large number of individuals. Whether the difference in behaviour is based on individual recognition of one’s own group members or simply the discrimination based on familiarity remains unresolved. However, both mechanisms would be sufficient for group membership identification.     

Mit Leben füllen

Die folgende Fallschilderung soll die diagnostische überlappung zwischen der psychiatrischen Diagnose „Depression“ und der rheumatologischen Diagnose „Fibromyalgie“ darstellen.