Alien Registration- Densmore, Nellie F. (Portland, Cumberland County)

https://digitalmaine.com/alien_docs/24626/thumbnail.jp

Quantitative reconstruction of late Holocene surface evolution on an alpine debris-flow fan

Debris-flow fans form a ubiquitous record of past debris-flow activity in mountainous areas, and may be useful for inferring past flow characteristics and consequent future hazard. Extracting information on past debris flows from fan records, however, requires an understanding of debris-flow deposition and fan surface evolution; field-scale studies of these processes have been very limited. In this paper, we document the patterns and timing of debris-flow deposition on the surface of the large and exceptionally active Illgraben fan in southwestern Switzerland. We use terrain analysis, radiocarbon dating of sediment fill in the Illgraben catchment, and cosmogenic 10Be and 36Cl exposure dating of debris-flow deposits on the fan to constrain the temporal evolution of the sediment routing system in the catchment and on the fan during the past 3200 years. We show that the fan surface preserves a set of debris-flow lobes that were predominantly deposited after the occurrence of a large rock avalanche near the fan apex at about 3200 years ago. This rock avalanche shifted the apex of the fan and impounded sediment within the Illgraben catchment. Subsequent evolution of the fan surface has been governed by both lateral and radial shifts in the active depositional lobe, revealed by the cosmogenic radionuclide dates and by cross-cutting geometrical relationships on the fan surface. This pattern of frequent avulsion and fan surface occupation provides field-scale evidence of the type of large-scale compensatory behavior observed in experimental sediment routing systems

Effects of trauma-related cues on pain processing in posttraumatic stress disorder: an fMRI investigation

Background: Imaging studies of pain processing in primary psychiatric disorders are just emerging. This study explored the neural correlates of stress-induced analgesia in individuals with posttraumatic stress disorder (PTSD). It combined functional magnetic resonance imaging (fMRI) and the traumatic script-driven imagery symptom provocation paradigm to examine the effects of trauma-related cues on pain perception in individuals with PTSD. Methods: The study included 17 patients with PTSD and 26 healthy, trauma-exposed controls. Participants received warm (nonpainful) or hot (painful) thermal stimuli after listening to a neutral or a traumatic script while they were undergoing an fMRI scan at a 4.0 T field strength. Results: Between-group analyses revealed that after exposure to the traumatic scripts, the blood oxygen level–dependent (BOLD) signal during pain perception was greater in the PTSD group than the control group in the head of the caudate. In the PTSD group, strong positive correlations resulted between BOLD signal and symptom severity in a number of brain regions previously implicated in stress-induced analgesia, such as the thalamus and the head of the caudate nucleus. Trait dissociation as measured by the Dissociative Experiences Scale correlated negatively with the right amygdala and the left putamen. Limitations: This study included heterogeneous traumatic experiences, a different proportion of military trauma in the PTSD versus the control group and medicated patients with PTSD. Conclusion: These data indicate that in patients with PTSD trauma recall will lead in a state-dependent manner to greater activation in brain regions implicated in stress-induced analgesia. Correlational analyses lend support to cortical hyperinhibition of the amygdala as a function of dissociation

Rethinking the off-grid city

This is the final version. Available on open access from Routledge via the DOI in this recordThere has been a resurgence in interest in the off-grid city, with a focus on off-grid urban spaces in the Global South, and on how the off-grid functions as a collection of places, lived spaces, and dynamic infrastructural configurations. As scholars and practitioners working in the off-grid urban context in South Africa, we contend it is necessary to question the assumptions of the “off-grid” concept in urban geography in terms of its implications for conducting research. We thereby identify four areas for further conceptual and empirical elaboration. The first area concerns the importance of continuing to redefine academic and practical understandings of the “grid”, ultimately moving to redefine its meaning in the city. The second is a need to decolonise and decentre the relationship between global and technocratic urban development “standards”, practices and discourses, and the granular off-grid context. The third area is the imperative of critically engaging with narratives of inadequacy and imperfection as often applied to off-grid, informal urban spaces. The fourth is the priority of moving towards a needs-based approach to off-grid development, with a focus on co-production of urban knowledge with local communities to ensure their needs and interests are met.British Academ

Beyond the Grid: The Micropolitics of Off-Grid Energy in Qandu-Qandu, South Africa

This is the final version. Available on open access from Wiley via the DOI in this recordIn this paper, we argue using smart technologies beyond the grid disrupts the access and use of existing energy sources, with profound impacts on everyday social life. We show how off-grid smart energy solutions constitute their own politics when considering existing conceptualisations of urban infrastructures in geography and the social sciences. To expose its politics, or “micropolitics”, we consider how tensions occur at the interface between infrastructures, where there are additions and modifications. We draw on an empirical example of Qandu-Qandu, an informal settlement in South Africa, to highlight how the placement, technical capabilities, and flexible financing options associated with off-grid solar energy create micropolitics with profound implications for everyday life. To conclude, we reflect on the value of using disruptions for understanding and enhancing equity in off-grid settings, contributing to the broader sustainability transitions narrative, and its “liveliness”

Smart and disruptive infrastructures: Re-building knowledge on the informal city

This is the final version. Available on open access from SAGE Publications via the DOI in this recordSmart urbanism is an established research area in geography and the social sciences. We draw on ‘worlding-provincialising’ strategies identified in an Urban Studies Special Issue from February 2021 to explore how smart infrastructures, a form of smart urbanism, disrupt representations of informality and urban development in new and productive ways. Focussing on the disruptive or troublesome implications of smart infrastructures reveals site-level considerations for developing policy and practice, where acknowledging the nuanced context for its use can present opportunities for not only understanding energy transitions in the Global South, but also creates opportunities for cross-learning. Drawing on our collective insights on a solar mini-grid project in Qandu-Qandu, Cape Town, we sketch out three ways the disruptive aspects of solar energy can be helpful for re-building knowledge on the informal city by: (i) re-positioning notions of ‘formal’ and ‘informal’ infrastructure(s) in urban planning and policymaking; (ii) highlighting new avenues for citizen autonomy; and (iii) recasting the informal city as a site for continuous innovation and learning.British AcademyUK Newton Fun

Dynamic Causal Modeling in PTSD and Its Dissociative Subtype: Bottom-Up Versus Top-Down Processing Within Fear and Emotion Regulation Circuitry

Posttraumatic stress disorder (PTSD) is associated with decreased top–down emotion modulation from medial prefrontal cortex (mPFC) regions, a pathophysiology accompanied by hyperarousal and hyperactivation of the amygdala. By contrast, PTSD patients with the dissociative subtype (PTSD + DS) often exhibit increased mPFC top–down modulation and decreased amygdala activation associated with emotional detachment and hypoarousal. Crucially, PTSD and PTSD + DS display distinct functional connectivity within the PFC, amygdala complexes, and the periaqueductal gray (PAG), a region related to defensive responses/emotional coping. However, differences in directed connectivity between these regions have not been established in PTSD, PTSD + DS, or controls. Methods: To examine directed (effective) connectivity among these nodes, as well as group differences, we conducted resting-state stochastic dynamic causal modeling (sDCM) pairwise analyses of coupling between the ventromedial (vm)PFC, the bilateral basolateral and centromedial (CMA) amygdala complexes, and the PAG, in 155 participants (PTSD [n = 62]; PTSD + DS [n = 41]; age-matched healthy trauma-unexposed controls [n = 52]). Results: PTSD was characterized by a pattern of predominant bottom–up connectivity from the amygdala to the vmPFC and from the PAG to the vmPFC and amygdala. Conversely, PTSD + DS exhibited predominant top–down connectivity between all node pairs (from the vmPFC to the amygdala and PAG, and from the amygdala to the PAG). Interestingly, the PTSD + DS group displayed the strongest intrinsic inhibitory connections within the vmPFC. Conclusions: These results suggest the contrasting symptom profiles of PTSD and its dissociative subtype (hyper- vs. hypo-emotionality, respectively) may be driven by complementary changes in directed connectivity corresponding to bottom–up defensive fear processing versus enhanced top–down regulation

A New Horned Crocodile from the Plio-Pleistocene Hominid Sites at Olduvai Gorge, Tanzania

BACKGROUND: The fossil record reveals surprising crocodile diversity in the Neogene of Africa, but relationships with their living relatives and the biogeographic origins of the modern African crocodylian fauna are poorly understood. A Plio-Pleistocene crocodile from Olduvai Gorge, Tanzania, represents a new extinct species and shows that high crocodylian diversity in Africa persisted after the Miocene. It had prominent triangular "horns" over the ears and a relatively deep snout, these resemble those of the recently extinct Malagasy crocodile Voay robustus, but the new species lacks features found among osteolaemines and shares derived similarities with living species of Crocodylus. METHODOLOGY/PRINCIPAL FINDINGS: The holotype consists of a partial skull and skeleton and was collected on the surface between two tuffs dated to approximately 1.84 million years (Ma), in the same interval near the type localities for the hominids Homo habilis and Australopithecus boisei. It was compared with previously-collected material from Olduvai Gorge referable to the same species. Phylogenetic analysis places the new form within or adjacent to crown Crocodylus. CONCLUSIONS/SIGNIFICANCE: The new crocodile species was the largest predator encountered by our ancestors at Olduvai Gorge, as indicated by hominid specimens preserving crocodile bite marks from these sites. The new species also reinforces the emerging view of high crocodylian diversity throughout the Neogene, and it represents one of the few extinct species referable to crown genus Crocodylus