Perfusion Fixation With Glutaraldehyde and Post-Fixation With Osmium Tetroxide for Electron Microscopy

The conductivity of cerebral cortex drops during perfusion with glutaraldehyde in 5 min to about 60% of the original value, to remain unchanged during the subsequent 10-15 min of perfusion. Circulatory arrest causes a similar drop in the tissue conductivity. Perfusion of asphyxiated tissue with glutaraldehyde does not produce additional major changes in the conductivity. Perfusion of the cortex with an osmium tetroxide solution causes an initial drop in conductivity. However, after about 3 min this trend is reversed and the conductivity increases again to close to the pre-perfusion value. Perfusion of asphyxiated cortex with OsO4 causes a marked increase of the conductivity. So does perfusion with an OsO4 solution of tissue previously treated with glutaraldehyde. One interpretation of these impedance changes is that glutaraldehyde perfusion causes, like asphyxiation, a transport of extracellular material into the intracellular compartment and that during OsO4 perfusion an extracellular space is again created. This possibility is supported by electron micrographs made of this material. Cerebral cortex perfused with glutaraldehyde and post-fixed with OsO4 shows electron-transparent dendritic elements and to a lesser extent pre-synaptic terminals, which seem to be swollen. When the cortex is flooded with a salt solution during glutaraldehyde perfusion the dendrites exhibit ballooning in the surface layer of the cortex, suggesting that the fluid on the cortex participates in the swelling. The tissue elements in the glutaraldehyde-perfused and OsO4 post-fixed cortex are separated by narrow extracellular spaces. The latter may have been produced by the OsO4 perfusion as is suggested by a comparison of micrographs prepared by freeze substitution (which tends to preserve the water distribution) of glutaraldehyde-perfused but not post-fixed cortex with micrographs of cortex treated with OsO4 after the glutaraldehyde perfusion. In accordance with the conductivity changes, the former micrographs showed very little extracellular space, and in many places tight junctions, whereas the latter showed clefts between the tissue elements

Feeling torn and fearing rue: Attitude ambivalence and anticipated regret as antecedents of biased information seeking

Theoretical work on attitudinal ambivalence suggests that anticipated regret may play a role in causing awareness of contradictions that subsequently induce a feeling of an evaluative conflict. In the present paper we empirically examined how the anticipation of regret relates to the association between the simultaneous presence of contradictory cognitions and emotions (objective ambivalence), and the evaluative conflict associated with it (subjective ambivalence), in the context of decision-making. Across three studies (Ns = 204,127,244), manipulating both objective ambivalence and regret, we consistently found that when a dichotomous ambivalent choice had to be made, (objectively) ambivalent attitude holders for whom feelings of anticipated regret were made salient reported higher levels of subjective-attitude ambivalence than participants in the other conditions. Moreover, in Studies 2 and 3 we found that the effect of anticipated regret on subjective ambivalence had consequences on information processing. Specifically, anticipating regret made ambivalent participants search for attitude-congruent information. This effect was mediated by the increase in subjective ambivalence. This work provides the first empirical evidence for the role of regret in the association between objective-and- subjective attitude ambivalence, and its consequences

Who Is Skeptical About Scientific Innovation? Examining Worldview Predictors of Artificial Intelligence, Nanotechnology, and Human Gene Editing Attitudes

This work examines worldview predictors of attitudes toward nanotechnology, human gene editing (HGE), and artificial intelligence. By simultaneously assessing the relative predictive value of various worldview variables in two Dutch samples (total N = 614), we obtained evidence for spirituality as a key predictor of skepticism across domains. Religiosity consistently predicted HGE skepticism only. Lower faith in science contributed to these relationships. Aversion to tampering with nature predicted skepticism across domains. These results speak to the importance of religiosity and spirituality for scientific innovation attitudes and emphasize the need for a detailed consideration of worldviews that shape these attitudes

Inmate emotion coping and psychological and physical well-being: The use of crying over spilled milk

The study investigated the relation between coping strategies of inmates and their psychological and physical well-being. General affective states such as optimism were related to both psychological and physical well-being. Moreover, inmates who experienced specific negative emotions such as regret, anxiety, and sadness reported more psychological and physical complaints. The way in which inmates coped with these negative emotions was also important. Inmates who used an active emotion-focused coping strategy were in better health than inmates inclined to keep their negative feelings to themselves. Emotion-focused coping by sharing negative emotions with people in one's social network can help to increase both psychological and physical well-being. Engaging in emotion management in a more cognitive way, by emphasizing positive aspects of the situation, can help to reduce the intensity of negative emotions. Possible research and policy implications of these results are discussed. © 2007 American Association for Correctional and Forensic Psychology

A Psychological Network Approach to Attitudes and Preventive Behaviors During Pandemics: A COVID-19 Study in the United Kingdom and the Netherlands

Preventive behaviors are crucial to prevent the spread of the coronavirus causing COVID-19. We adopted a complex psychological systems approach to obtain a descriptive account of the network of attitudes and behaviors related to COVID-19. A survey study (N = 1,022) was conducted with subsamples from the United Kingdom (n = 502) and the Netherlands (n = 520). The results highlight the importance of people’s support for, and perceived efficacy of, the measures and preventive behaviors. This also applies to the perceived norm of family and friends adopting these behaviors. The networks in both countries were largely similar but also showed notable differences. The interplay of psychological factors in the networks is also highlighted, resulting in our appeal to policy makers to take complexity and mutual dependence of psychological factors into account. Future research should study the effects of interventions aimed at these factors, including effects on the network, to make causal inferences