The role of selective attention in the positivity offset: Evidence from event related potentials

Some research suggests that positive and negative valence stimuli may be processed differently. For example, negative material may capture and hold attention more readily than equally arousing positive material. This is called the negativity bias, and it has been observed as both behavioural and electroencephalographic (EEG) effects. Consequently, it has been attributed to both automatic and elaborative processes. However, at the lowest levels of arousal, faster reaction times and stronger EEG responses to positive material have been observed. This is called the positivity offset, and the underlying cognitive mechanism is less understood. To study the role of selective attention in the positivity offset, participants completed a negative affective priming (NAP) task modified to dissociate priming for positive and negative words. The task required participants to indicate the valence of a target word, while simultaneously ignoring a distractor. In experiment 1, a behavioural facilitation effect (faster response time) was observed for positive words, in stark contrast to the original NAP task. These results were congruent with a previously reported general categorization advantage for positive material. In experiment 2, participants performed the task while EEG was recorded. In additional to replicating the behavioural results from experiment 1, positive words elicited a larger Late Positive Potential (LPP) component on ignored repetition relative to control trials. Surprisingly, negative words elicited a larger LPP than positive words on control trials. These results suggest that the positivity offset may reflect a greater sensitivity to priming effects due to a more flexible attentional set.

Neuropathology of SCA34 showing widespread oligodendroglial pathology with vacuolar white matter degeneration: a case study

Spinocerebellar ataxia type 34 (SCA34) is an autosomal dominant inherited ataxia due to mutations in ELOVL4, which encodes one of the very long-chain fatty acid elongases. SCA38, another spinocerebellar ataxia, is caused by mutations in ELOVL5, a gene encoding another elongase. However, there have been no previous studies describing the neuropathology of either SCA34 or 38. This report describes the neuropathological findings of an 83-year-old man with SCA34 carrying a pathological ELOVL4 mutation (NM_022726, c.736T>G, p.W246G). Macroscopic findings include atrophies in the pontine base, cerebellum, and cerebral cortices. Microscopically, marked neuronal and pontocerebellar fiber loss was observed in the pontine base. In addition, in the pontine base, accumulation of CD68-positive macrophages laden with periodic acid-Schiff (PAS)-positive material was observed. Many vacuolar lesions were found in the white matter of the cerebral hemispheres and, to a lesser extent, in the brainstem and spinal cord white matter. Immunohistological examination and ultrastructural observations with an electron microscope suggest that these vacuolar lesions are remnants of degenerated oligodendrocytes. Electron microscopy also revealed myelin sheath destruction. Unexpectedly, aggregation of the four-repeat tau was observed in a spatial pattern reminiscent of progressive supranuclear palsy. The tau lesions included glial fibrillary tangles resembling tuft-shaped astrocytes and neurofibrillary tangles and pretangles. This is the first report to illustrate that a heterozygous missense mutation in ELOVL4 leads to neuronal loss accompanied by macrophages laden with PAS-positive material in the pontine base and oligodendroglial degeneration leading to widespread vacuoles in the white matter in SCA34.

‘Leaving a record of their coming’

Creature from the Black Lagoon (Arnold US 1954), perhaps the quintessential and most enduring atomic-age creature feature, is a rich text for ecocritical analysis. Not only does the film heavily emphasise extinction and evolution in its narration and plot line, but the film is full of tensions that both calcify problematic Anthropocenic narratives and erode them. The film offers us a way of critiquing Anthropocenic histories and ongoing narratives without erasing racial and colonial injustices. It also offers us a way to imagine other stories - other ways of writing on our world - that engage material entanglements, disorient colonial and anthropocentric perspectives and create empathy. Recognising the film’s rocky Anthropocenic and extinction narratives enables a more fluid approach. Reading through water, emphasising evolutionary entanglements, brings into high relief past injustices against humans and nonhumans, and it engages a palimpsest effect, where an awareness of our muddled materiality helps us write over hierarchical pasts. Framing the film ecocritically by reading extinction and evolution emphasises the tensions of Anthropocenic violence (through colonial science and Anthropocenic erasures) and of positive material entanglements (through empathy and disorientation).

What are we voting for? Opposition alliance joint campaigns in electoral autocracies

Existing analyses of opposition pre-electoral alliance formation in electoral autocracies neglect their coordinated election campaigns against incumbent autocrats. This paper argues that opposition alliance joint campaigns can increase the salience of the anti-regime cleavage, signal mutual compromise, and highlight the positive material and policy gains voters will reap following regime defeat. Together, they persuade ideologically and ethnically disparate opposition supporters to engage in the cross-party strategic voting necessary to maximize opposition vote share and their chances of winning. Empirical findings from Malaysia’s historic 2018 general elections support the theory’s propositions. A pre-electoral survey experiment estimates that an opposition alliance’s joint campaigns increases cross-party strategic voting by about 10 percentage points among opposition voters. Field interviews and ethnographic observation during the election campaigning revealed the diverse methods and mechanisms of joint campaigns. Malaysia’s Pakatan Harapan opposition alliance eventually prevailed through a combination of joint campaigning against a flailing incumbent.

3D flower-like molybdenum disulfide modified graphite felt as a positive material for vanadium redox flow batteries

The open flower-like structure facilitates vanadium ion transport. The capacity and efficiency of a battery using MoS2/GF are dramatically increased.

Glial Cell Architecture Dynamics in Dentate Gyrus and CA4 Area of Wistar Rat Hippocampus Following 20-minute Occlusion of Common Carotid Arteries

Aim. To study the distribution and spatial organization of dentate gyrus (DG) astrocytes and CA4 area of hippocampus of Wistar rats following 20-minute occlusion of common carotid arteries (OCCA) compared to sham-operated control animals.Material and methods. Histological (Nissl staining with hematoxylin and eosin), immunohistochemical (GFAP, MAP-2) and morphometric methods were used. Astrocytes and neurons in control (sham-operated animals, n = 5) group, after 6 hours (n=5), 1 days (n=5), 3 days (n=5), 7 days (n=5), 14 days (n=5) and 30 days (n=5) after 20-minute OCCA were studied on thin (4 µm) serial frontal sections of the hippocampus. Fractal analysis (ImageJ 1.52; fraclac 2.5 plugin) was used to obtain additional quantitative information on the spatial organization of astrocyte networks. Statistical hypotheses were tested using nonparametric criteria.Results. 30 days after the 20-minute OCCA, only 5.3% of CA4 neurons were irreversibly destroyed and the total numerical density of DG granular cells remained at the control level. Hypertrophy and increased complexity of the spatial organization of astrocyte processes were observed 6 hours and 1 day after OCCA and persisted for 30 days. Astrogliosis was accompanied by an increased relative area of GFAP-positive material and fractal dimension and reduced lacunarity of the astrocyte network. The latter was especially evident in 1, 14 and 30 days after the OCCA.Conclusion. After the 20-minute OCCA, the density of GFAP-positive material increased, the fibroarchitecture reorganized and gained more complexity due to the branching of astrocyte processes. At the same time, the total numerical density of neurons changed only slightly. All this indicated the probable role of astrocytes in post-ischemic activation of natural neuroprotection mechanisms.