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Layer after Layer
(2021)
When the Royal Botanic Gardens at Kew in South London were opened to the general public in the 1840s, they were presented as a ‘world text’: a collection of flora from all over the world, with the spectacular tropical (read: colonial) specimens taking centre stage as indexes of Britain’s imperial supremacy. However, the one exotic plant species that preoccupied the British cultural imagination more than any other remained conspicuously absent from the collection: the banyan tree, whose non-transferability left a significant gap in the ‘text’ of the garden, thereby effectively puncturing the illusion of comprehensive global command that underpins the biopolitical designs of what Richard Grove has aptly dubbed ‘green imperialism’. This article demonstrates how, in the 19th and early 20th centuries, the banyan tree became an object of fascination and admiration for British scientists, painters, writers and photographers precisely because of its obstinate non-availability to colonial control and visual or even conceptual representability.
This paper reads ‘The Detainee’s Tale as told to Ali Smith’ (2016) as an exemplary demonstration of the work of world literature. Smith’s story articulates an ethics of reading that is grounded in the recipient’s openness to the singular, unpredictable, and unverifiable text of the other. More specifically, Smith’s account enables the very event that it painstakingly stages: the encounter with alterity and newness, which is both the theme of the narrative and the effect of the text on the reader. At the same time, however, the text urges to move from an ethics of literature understood as the responsible reception of the other by an individual reader to a more explicitly convivial and political ethics of commitment beyond the scene of reading.
Postcolonial criticism has repeatedly debunked the ostensible neutrality of the ‘world’ of world literature by pointing out that and how the contemporary world – whether conceived in terms of cosmopolitan conviviality or neoliberal globalization – cannot be understood without recourse to the worldly event of Europe’s colonial expansion. While we deem this critical perspective indispensable, we simultaneously maintain that to reduce ‘the world’ to the world-making impact of capital, colonialism, and patriarchy paints an overly deterministic picture that runs the risk of unwittingly reproducing precisely that dominant ‘oneworldness’ that it aims to critique. Moreover, the mere potentiality of alternative modes of world-making tends to disappear in such a perspective so that the only remaining option to think beyond oneworldness resides in the singularity claim. This insistence on singularity, however, leaves the relatedness of the single units massively underdetermined or denies it altogether. By contrast, we locate world literature in the conflicted space between the imperial imposition of a hierarchically stratified world (to which, as hegemonic forces tell us, ‘there is no alternative’) and the unrealized ‘undivided world’ that multiple minor cosmopolitan projects yet have to win. It is precisely the tension between these ‘two worlds’ that brings into view the crucial centrality not of the nodes in their alleged singularity but their specific relatedness to each other, that both impedes and energizes world literature today and renders it ineluctably postcolonial.
Die schrumpfende Mittelschicht ist nicht nur in der Öffentlichkeit ein vieldiskutierter Themenbereich. Eine Vielzahl an wissenschaftlichen Fachdisziplinen setzt sich aus unterschiedlichen Perspektiven mit der Mittelschicht im Kontext des Wandels von Schichtungsgefügen auseinander. Während die gesellschaftliche Mitte in Deutschland ein etabliertes Forschungsgebiet ist, liegen für Österreich hingegen bislang kaum Studien vor. Vor diesem Hintergrund vereint der Sammelband konzeptionelle und empirische Beiträge zur österreichischen Mittelschicht aus Soziologie, Politikwissenschaften, Staatswissenschaft, und Zeitgeschichte. Ziel ist die umfassende multidisziplinäre Darstellung des Status Quo der Mittelschicht in Österreich. Die Beiträge in diesem Sammelband bieten einen Überblick über historische Perspektiven, unterschiedliche Theorietraditionen, sowie gegenwärtige empirische Befunde und sozialpolitische Analysen.
'Complex systems are information processors' is a statement that is frequently made. Here we argue for the distinction between information processing-in the sense of encoding and transmitting a symbolic representation-and the formation of correlations (pattern formation/self-organisation). The study of both uses tools from information theory, but the purpose is very different in each case: explaining the mechanisms and understanding the purpose or function in the first case, versus data analysis and correlation extraction in the latter. We give examples of both and discuss some open questions. The distinction helps focus research efforts on the relevant questions in each case.
Insulin is the main anabolic hormone secreted by 13-cells of the pancreas stimulating the assimilation and storage of glucose in muscle and fat cells. It modulates the postprandial balance of carbohydrates, lipids and proteins via enhancing lipogenesis, glycogen and protein synthesis and suppressing glucose generation and its release from the liver. Resistance to insulin is a severe metabolic disorder related to a diminished response of peripheral tissues to the insulin action and signaling. This leads to a disturbed glucose homeostasis that precedes the onset of type 2 diabetes (T2D), a disease reaching epidemic proportions. A large number of studies reported an association between elevated circulating fatty acids and the development of insulin resistance. The increased fatty acid lipid flux results in the accumulation of lipid droplets in a variety of tissues. However, lipid intermediates such as diacylglycerols and ceramides are also formed in response to elevated fatty acid levels. These bioactive lipids have been associated with the pathogenesis of insulin resistance. More recently, sphingosine 1-phosphate (S1P), another bioactive sphingolipid derivative, has also been shown to increase in T2D and obesity. Although many studies propose a protective role of S1P metabolism on insulin signaling in peripheral tissues, other studies suggest a causal role of S1P on insulin resistance. In this review, we critically summarize the current state of knowledge of S1P metabolism and its modulating role on insulin resistance. A particular emphasis is placed on S1P and insulin signaling in hepatocytes, skeletal muscle cells, adipocytes and pancreatic 13-cells. In particular, modulation of receptors and enzymes that regulate S1P metabolism can be considered as a new therapeutic option for the treatment of insulin resistance and T2D.
Despite their overt focus on inexplicable alien forces, cosmic horror stories are also determined by their human cast. Far from being merely fodder for horror, the characters significantly contribute to the generation of meaning, including that of the supernatural entity or phenomenon itself. The same holds for the narrators' (implicitly) political perspectives on the world of which they are part. Much of the perspective propounded in Lovecraft's cosmic horror stories partakes of myth, adopting in particular the latter's universal view and pronounced sidelining of humanity as a whole, which it intensifies to the point of horror. Appearances to the contrary notwithstanding, this universal perspective is consistent with the racism permeating and structuring Lovecraft's writing. Though eschewing racism and universalism, the cosmic horror of Kiernan's "Tidal Forces" negotiates literary reflections of colonialism from an unreflective white perspective.
Increasing greenhouse gas emissions are likely to impact not only natural systems but economies worldwide. If these impacts alter future economic development, the financial losses will be significantly higher than the mere direct damages. So far, potentially aggravating investment responses were considered negligible. Here we consistently incorporate an empirically derived temperature-growth relation into the simple integrated assessment model DICE. In this framework we show that, if in the next eight decades varying temperatures impact economic growth as has been observed in the past three decades, income is reduced by similar to 20% compared to an economy unaffected by climate change. Hereof similar to 40% are losses due to growth effects of which similar to 50% result from reduced incentive to invest. This additional income loss arises from a reduced incentive for future investment in anticipation of a reduced return and not from an explicit climate protection policy. Under economically optimal climate-change mitigation, however, optimal investment would only be reduced marginally as mitigation efforts keep returns high.
Process-based integrated assessment models (IAMs) project long-term transformation pathways in energy and land-use systems under what-if assumptions. IAM evaluation is necessary to improve the models’ usefulness as scientific tools applicable in the complex and contested domain of climate change mitigation. We contribute the first comprehensive synthesis of process-based IAM evaluation research, drawing on a wide range of examples across six different evaluation methods including historical simulations, stylised facts, and model diagnostics. For each evaluation method, we identify progress and milestones to date, and draw out lessons learnt as well as challenges remaining. We find that each evaluation method has distinctive strengths, as well as constraints on its application. We use these insights to propose a systematic evaluation framework combining multiple methods to establish the appropriateness, interpretability, credibility, and relevance of process-based IAMs as useful scientific tools for informing climate policy. We also set out a programme of evaluation research to be mainstreamed both within and outside the IAM community.
Background: Being an essential trace element, copper is involved in diverse physiological processes. However, excess levels might lead to adverse effects. Disrupted copper homeostasis, particularly in the brain, has been associated with human diseases including the neurodegenerative disorders Wilson and Alzheimer?s disease. In this context, astrocytes play an important role in the regulation of the copper homeostasis in the brain and likely in the prevention against neuronal toxicity, consequently pointing them out as a potential target for the neurotoxicity of copper. Major toxic mechanisms are discussed to be directed against mitochondria probably via oxidative stress. However, the toxic potential and mode of action of copper in astrocytes is poorly understood, so far. Methods: In this study, excess copper levels affecting human astrocytic cell model and their involvement in the neurotoxic mode of action of copper, as well as, effects on the homeostasis of other trace elements (Mn, Fe, Ca and Mg) were investigated. Results: Copper induced substantial cytotoxic effects in the human astrocytic cell line following 48 h incubation (EC30: 250 ?M) and affected mitochondrial function, as observed via reduction of mitochondrial membrane potential and increased ROS production, likely originating from mitochondria. Moreover, cellular GSH metabolism was altered as well. Interestingly, not only cellular copper levels were affected, but also the homeostasis of other elements (Ca, Fe and Mn) were disrupted. Conclusion: One potential toxic mode of action of copper seems to be effects on the mitochondria along with induction of oxidative stress in the human astrocytic cell model. Moreover, excess copper levels seem to interact with the homeostasis of other essential elements such as Ca, Fe and Mn. Disrupted element homeostasis might also contribute to the induction of oxidative stress, likely involved in the onset and progression of neurodegenerative disorders. These insights in the toxic mechanisms will help to develop ideas and approaches for therapeutic strategies against copper-mediated diseases.
Secretory Wnt trafficking can be studied in the polarized epithelial monolayer of Drosophila wing imaginal discs (WID). In this tissue, Wg (Drosophila Wnt-I) is presented on the apical surface of its source cells before being internalized into the endosomal pathway. Long-range Wg secretion and spread depend on secondary secretion from endosomal compartments, but the exact post-endocytic fate of Wg is poorly understood. Here, we summarize and present three protocols for the immunofluorescencebased visualization and quantitation of different pools of intracellular and extracellular Wg in WID: (1) steady-state extracellular Wg; (2) dynamic Wg trafficking inside endosomal compartments; and (3) dynamic Wg release to the cell surface. Using a genetic driver system for gene manipulation specifically at the posterior part of the WID (EnGal4) provides a robust internal control that allows for direct comparison of signal intensities of control and manipulated compartments of the same WID. Therefore, it also circumvents the high degree of staining variability usually associated with whole-tissue samples. In combination with the genetic manipulation of Wg pathway components that is easily feasible in Drosophila, these methods provide a tool-set for the dissection of secretory Wg trafficking and can help us to understand how Wnt proteins travel along endosomal compartments for short-and long-range signal secretion.
The response of the hydrogen molecular ion, H-2(+), to few-cycle laser pulses of different intensities is simulated. To treat the coupled electron-nuclear motion, we use adiabatic potentials computed with Gaussian-type basis sets together with a heuristic ionization model for the electron and a grid representation for the nuclei. Using this mixed-basis approach, the time-dependent Schrodinger equation is solved, either within the Born-Oppenheimer approximation or with nonadiabatic couplings included. The dipole response spectra are compared to all-grid-based solutions for the three-body problem, which we take as a reference to benchmark the Gaussian-type basis set approaches. Also, calculations employing the fixed-nuclei approximation are performed, to quantify effects due to nuclear motion. For low intensities and small ionization probabilities, we get excellent agreement of the dynamics using Gaussian-type basis sets with the all-grid solutions. Our investigations suggest that high harmonic generation (HHG) and high-frequency response, in general, can be reliably modeled using Gaussian-type basis sets for the electrons for not too high harmonics. Further, nuclear motion destroys electronic coherences in the response spectra even on the time scale of about 30 fs and affects HHG intensities, which reflect the electron dynamics occurring on the attosecond time scale. For the present system, non-Born-Oppenheimer effects are small. The Gaussian-based, nonadiabatically coupled, time-dependent multisurface approach to treat quantum electron-nuclear motion beyond the non-Born-Oppenheimer approximation can be easily extended to approximate wavefunction methods, such as time-dependent configuration interaction singles (TD-CIS), for systems where no benchmarks are available.
Ausgehend von der Teilung in nichtaktive (Haushalt) und aktive Bevölkerung (Markt) fragt der Beitrag nach der Rolle, die statistische Vergleichsverfahren bei dieser Grenzziehung in der Welt der Arbeit spielen. Dies geschieht vor dem Hintergrund der Verzweigung von zwei strukturellen Entwicklungen, nämlich dem Wandel der (Arbeits‑)Welten und der statistischen Vergleichsverfahren. Der Beitrag gehört zu den ersten, der diese Nahtstelle systematisch und empirisch an der nationalen und internationalen (Beschäftigungs‑)Statistik untersucht. In diesem Beitrag schlage ich vor, die beiden Beobachtungsebenen als ein Feld der inter/nationalen Statistik zu verstehen. Ihre Ähnlichkeiten, Unterschiede und Verzweigungen werden soziologisch bislang noch nicht wahrgenommen. Im Unterschied dazu behandele ich sie aus einer wissensgeschichtlichen und wissenssoziologischen Perspektive gemeinsam hinsichtlich ihrer Selektionsleistungen, Beobachtungsinstrumente und Beschreibungsebenen. Die Ergebnisse zeigen die zunehmende Spezifizierung und Ausdehnung der ökonomischen Dimension von Arbeitstätigkeiten, die durch die Ordnungstechniken der inter/nationalen Statistik, verstärkt nach 1945, forciert werden. Diese Verschiebungen, so das Argument, sind eng mit dem Aufstieg des technischen Wissens im „technical internationalism“ verbunden, die nach 1945 das statistische und das Alltagsverständnis von der wirtschaftlich nichtaktiven Haushaltsarbeit bekräftigen.
The scapula plays a significant role in efficient shoulder movement. Thus, alterations from typical scapular motion during upper limb movements are thought to be associated with shoulder pathologies. However, a clear understanding of the relationship is not yet obtained.. Scapular alterations may only represent physiological variability as their occurrence can appear equally as frequent in individuals with and without shoulder disorders. Evaluation of scapular motion during increased load might be a beneficial approach to detect clinically relevant alterations. However, functional motion adaptations in response to maximum effort upper extremity loading has not been established yet. Therefore, the overall purpose of this research project was to give further insight in physiological adaptations of scapular kinematics and their underlying scapular muscle activity in response to high demanding shoulder movements in healthy asymptomatic individuals. Prior to the investigation of the effect of various load situation, the reproducibility of scapular kinematics and scapular muscle activity were evaluated under maximum effort arm movements. Healthy asymptomatic adults performed unloaded and maximal loaded concentric and eccentric isokinetic shoulder flexion and extension movements in the scapular plane while scapular kinematics and scapular muscle activity were simultaneously assessed. A 3D motion capture system (infra-red cameras & reflective markers) was utilized to track scapular and humerus motion in relation to the thorax. 3D scapular position angles were given for arm raising and lowering between humerus positions of 20° and 120° flexion. To further characterize the scapular pattern, the scapular motion extent and scapulohumeral rhythm (ratio of scapular and humerus motion extent) were determined. Muscle activity of the upper and lower trapezius and the serratus anterior were assessed with surface electromyography. Amplitudes were calculated for the whole ROM and four equidistant movement phases. Reliability was characterized by overall moderate to good reproducibility across the load conditions. Irrespective of applied load, scapular kinematics followed a motion pattern of continuous upward rotation, posterior tilt and external rotation during arm elevation and a continuous downward rotation, anterior tilt and internal rotation during arm lowering. However, kinematics were altered between maximal loaded and unloaded conditions showing increased upward rotation, reduced posterior tilt and external rotation. Further, the scapulohumeral rhythm was decreased and scapular motion extent increased under maximal loaded movements. Muscle activity during maximum effort were of greater magnitude and differed in their pattern in comparison to the continuous increase and decrease of activity during unloaded shoulder flexion and extension. Relationships between scapular kinematics and their underlying scapular muscle activity could only be identified for a few isolated combinations, whereas the majority showed no associations. Scapular kinematics and scapular muscle activity pattern alter according to the applied load. Alterations between the load conditions comply in magnitude and partially in direction with differences seen between symptomatic and asymptomatic individuals. Even though long-term effects of identified adaptations in response to maximum load are so far unclear, deviations from typical scapular motion or muscle activation should not per se be seen as indicators of shoulder impairment. However, evaluation of alterations in scapular motion and activation in response to maximum effort may have the potential to identify individuals that are unable to cope with increased upper limb demands. Findings further challenge the understanding of scapular motion and stabilization by the trapezius and serratus anterior muscles, as clear relationships between the underlying scapular muscle activity and scapular kinematics were neither observed during unloaded nor maximal loaded shoulder movements.
Characterization of scapular kinematics under demanding load conditions might aid to distinguish between physiological and clinically relevant alterations. Previous investigations focused only on submaximal external load situations. How scapular movement changes with maximal load remains unclear. Therefore, the present study aimed to evaluate 3D scapular kinematics during unloaded and maximal loaded shoulder flexion and extension. Twelve asymptomatic individuals performed shoulder flexion and extension movements under unloaded and maximal concentric and eccentric loaded isokinetic conditions. 3D scapular kinematics assessed with a motion capture system was analyzed for 20° intervals of humeral positions from 20° to 120° flexion. Repeated measures ANOVAs were used to evaluate kinematic differences between load conditions for scapular position angles, scapulohumeral rhythm and scapular motion extent. Increased scapular upward rotation was seen during shoulder flexion and extension as well as decreased posterior tilt and external rotation during eccentric and concentric arm descents of maximal loaded compared to unloaded conditions. Load effects were further seen for the scapulohumeral rhythm with greater scapular involvement at lower humeral positions and increased scapular motion extent under maximal loaded shoulder movements. With maximal load applied to the arm physiological scapular movement pattern are induced that may imply both impingement sparing and causing mechanisms.
Biodiversity decline causes a loss of functional diversity, which threatens ecosystems through a dangerous feedback loop: This loss may hamper ecosystems’ ability to buffer environmental changes, leading to further biodiversity losses. In this context, the increasing frequency of human-induced excessive loading of nutrients causes major problems in aquatic systems. Previous studies investigating how functional diversity influences the response of food webs to disturbances have mainly considered systems with at most two functionally diverse trophic levels. We investigated the effects of functional diversity on the robustness, that is, resistance, resilience, and elasticity, using a tritrophic—and thus more realistic—plankton food web model. We compared a non-adaptive food chain with no diversity within the individual trophic levels to a more diverse food web with three adaptive trophic levels. The species fitness differences were balanced through trade-offs between defense/growth rate for prey and selectivity/half-saturation constant for predators. We showed that the resistance, resilience, and elasticity of tritrophic food webs decreased with larger perturbation sizes and depended on the state of the system when the perturbation occurred. Importantly, we found that a more diverse food web was generally more resistant and resilient but its elasticity was context-dependent. Particularly, functional diversity reduced the probability of a regime shift toward a non-desirable alternative state. The basal-intermediate interaction consistently determined the robustness against a nutrient pulse despite the complex influence of the shape and type of the dynamical attractors. This relationship was strongly influenced by the diversity present and the third trophic level. Overall, using a food web model of realistic complexity, this study confirms the destructive potential of the positive feedback loop between biodiversity loss and robustness, by uncovering mechanisms leading to a decrease in resistance, resilience, and potentially elasticity as functional diversity declines.
The use of acidic ionic liquids and solids as electrolytes in fuel cells is an emerging field due to their efficient proton conductivity and good thermal stability. Despite multiple reports describing conducting properties of acidic ILs, little is known on the charge-transport mechanism in the vicinity of liquid-glass transition and the structural factors governing the proton hopping. To address these issues, we studied two acidic imidazolium-based ILs with the same cation, however, different anions-bulk tosylate vs small methanesulfonate. High-pressure dielectric studies of anhydrous and water-saturated materials performed in the close vicinity of T-g have revealed significant differences in the charge-transport mechanism in these two systems being undetectable at ambient conditions. Thereby, we demonstrated the effect of molecular architecture on proton hopping, being crucial in the potential electrochemical applications of acidic ILs.
Introduction
(2021)