Fuelled by ATP hydrolysis, dyneins generate force and movement on microtubules in a wealth of biological processes, including ciliary beating, cell division and intracellular transport. The large ...mass and complexity of dynein motors have made elucidating their mechanisms a sizable task. Yet, through a combination of approaches, including X-ray crystallography, cryo-electron microscopy, single-molecule assays and biochemical experiments, important progress has been made towards understanding how these giant motor proteins work. From these studies, a model for the mechanochemical cycle of dynein is emerging, in which nucleotide-driven flexing motions within the AAA+ ring of dynein alter the affinity of its microtubule-binding stalk and reshape its mechanical element to generate movement.
Lacanian Biopolitics of COVID-19 Burgess, J Peter
International studies quarterly,
06/2023, Volume:
67, Issue:
3
Journal Article
Peer reviewed
Abstract
A public debate has raged in Europe and the Americas for the last year, almost as predictable in its substance as in its form: Has the suppression of individual liberties, in the form of ...lockdowns, curfews, imposed mask-wearing, and vaccination justified by and indeed legitimated by the sanitary crisis? On virtually all levels of public debate, positions have been formulated on the right (or responsibility) of public authorities to require citizens to take measures in the name of their own personal health and the health of others. In International Studies, biopolitics has become the go-to concept for both analyzing and politicizing the COVID-19 pandemic. Three variants of biopolitical analysis dominate, overlapping, and mutually dependent: those stemming the insights of Foucault’s late work, those inspired by Agamben’s Homo Sacer, and those that extended the global analysis of Hardt and Negri. In a recently published book, The Inverse of Biopolitics, Laurent interprets biopolitics in an alternative vein, finding in the final phase of Lacan’s teaching, beginning around 1970, a preoccupation with the “speaking body,” condensed in the hybrid term parlêtre, both speaking-being and being-speaking. This article draws out the implications of this alternative conceptualization of biopolitics for the analysis of the COVID-19 pandemic.
This new Handbook gathers together state-of-the-art theoretical reflection and empirical research by a group of leading international scholars in the subdiscipline of Critical Security Studies.
In ...today's globalised setting, the challenge of maintaining security is no longer limited to the traditional foreign-policy and military tools of the nation-state, and security and insecurity are no longer considered as dependent only upon geopolitics and military strength, but rather are also seen to depend upon social, economic, environmental, ethical models of analysis and tools of action. The contributors discuss and evaluate this fundamental shift in four key areas:
New security concepts
New security subjects
New security objects
New security practices
Offering a comprehensive theoretical and empirical overview of this evolving field, this book will be essential reading for all students of critical security studies, human security, international/global security, political theory and IR in general.
J. Peter Burgess is Research Professor at PRIO, the International Peace Research Institute, Oslo, where he leads the Security Programme and edits the interdisciplinary journal Security Dialogue. In addition, he is Adjunct Professor at the Norwegian University of Science and Technology, Trondheim (NTNU), and Research Fellow at the Institute for European Studies, Brussels.
The severity of marine heatwaves (MHWs) that are increasingly impacting ocean ecosystems, including vulnerable coral reefs, has primarily been assessed using remotely sensed sea-surface temperatures ...(SSTs), without information relevant to heating across ecosystem depths. Here, using a rare combination of SST, high-resolution in-situ temperatures, and sea level anomalies observed over 15 years near Moorea, French Polynesia, we document subsurface MHWs that have been paradoxical in comparison to SST metrics and associated with unexpected coral bleaching across depths. Variations in the depth range and severity of MHWs was driven by mesoscale (10s to 100s of km) eddies that altered sea levels and thermocline depths and decreased (2007, 2017 and 2019) or increased (2012, 2015, 2016) internal-wave cooling. Pronounced eddy-induced reductions in internal waves during early 2019 contributed to a prolonged subsurface MHW and unexpectedly severe coral bleaching, with subsequent mortality offsetting almost a decade of coral recovery. Variability in mesoscale eddy fields, and thus thermocline depths, is expected to increase with climate change, which, along with strengthening and deepening stratification, could increase the occurrence of subsurface MHWs over ecosystems historically insulated from surface ocean heating by the cooling effects of internal waves.
The mammalian Pcdhg gene cluster encodes a family of 22 cell adhesion molecules, the gamma-Protocadherins (γ-Pcdhs), critical for neuronal survival and neural circuit formation. The extent to which ...isoform diversity-a γ-Pcdh hallmark-is required for their functions remains unclear. We used a CRISPR/Cas9 approach to reduce isoform diversity, targeting each Pcdhg variable exon with pooled sgRNAs to generate an allelic series of 26 mouse lines with 1 to 21 isoforms disrupted via discrete indels at guide sites and/or larger deletions/rearrangements. Analysis of 5 mutant lines indicates that postnatal viability and neuronal survival do not require isoform diversity. Surprisingly, given reports that it might not independently engage in trans-interactions, we find that γC4, encoded by Pcdhgc4, is the only critical isoform. Because the human orthologue is the only PCDHG gene constrained in humans, our results indicate a conserved γC4 function that likely involves distinct molecular mechanisms.
Understanding population dynamics is a long-standing objective of ecology, but the need for progress in this area has become urgent. For coral reefs, achieving this objective is impeded by a lack of ...information on settlement versus post-settlement events in determining recruitment and population size. Declines in coral abundance are often inferred to be associated with reduced densities of recruits, which could arise from mechanisms occurring at larval settlement, or throughout post-settlement stages. This study uses annual measurements from 2008 to 2021 of coral cover, the density of coral settlers (S), the density of small corals (SC), and environmental conditions, to evaluate the roles of settlement versus post-settlement events in determining rates of coral recruitment and changes in coral cover at Moorea, French Polynesia. Coral cover, S, SC, and the SC:S ratio (a proxy for post-settlement success), and environmental conditions, were used in generalized additive models (GAMs) to show that: (a) coral cover was more strongly related to SC and SC:S than S, and (b) SC:S was highest when preceded by cool seawater, low concentrations of Chlorophyll a, and low flow speeds, and S showed evidence of declining with elevated temperature. Together, these results suggest that changes in coral cover in Moorea are more strongly influenced by post-settlement events than settlement. The key to understanding coral community resilience may lie in elucidating the factors attenuating the bottleneck between settlers and small corals.
The insecurity of critique Burgess, J Peter
Security dialogue,
02/2019, Volume:
50, Issue:
1
Journal Article
Peer reviewed
Open access
‘Security’ is a uniquely rich object for critique. It rests on a long and noble conceptual history in Western thought. And yet the provision of security most often consists of a shoring up, through ...the discourses of nationality, ethnicity, political economy or even science, of what is assumed to be solid at its core but weakened through the contingencies of politics, society, ideology, and so on. The article argues that the critical force of critique stems from the fact that critique itself is a practice inescapably bound up with insecurity, and thus that the critique of security exercised since around 1997 as ‘critical security studies’ is self-replicating. By introducing concepts from Husserlian phenomenology, it attempts to show that insecurity is not a simple feature of an otherwise secure state of life, ripe for critical analysis that promises to expose its false premises. Rather, insecurity lies at the very foundation of critical thought. Building upon the bare and basic question, ‘What does it mean to mean?’, a phenomenology of security asks the straightforward question: ‘What is the security-ness of security?’ It permits one to ask what remains of security when all else is stripped away, what essential minimum must be retained in order for security to be security.
Response diversity in corals Burgess, Scott C.; Johnston, Erika C.; Wyatt, Alex S. J. ...
Ecology (Durham),
06/2021, Volume:
102, Issue:
6
Journal Article
Peer reviewed
Open access
Variation among functionally similar species in their response to environmental stress buffers ecosystems from changing states. Functionally similar species may often be cryptic species representing ...evolutionarily distinct genetic lineages that are morphologically indistinguishable. However, the extent to which cryptic species differ in their response to stress, and could therefore provide a source of response diversity, remains unclear because they are often not identified or are assumed to be ecologically equivalent. Here, we uncover differences in the bleaching response between sympatric cryptic species of the common Indo-Pacific coral, Pocillopora. In April 2019, prolonged ocean heating occurred at Moorea, French Polynesia. 72% of pocilloporid colonies bleached after 22 d of severe heating (>8°C-days) at 10 m depth on the north shore fore reef. Colony mortality ranged from 11% to 42% around the island four months after heating subsided. The majority (86%) of pocilloporids that died from bleaching belonged to a single haplotype, despite twelve haplotypes, representing at least five species, being sampled. Mitochondrial (open reading frame) sequence variation was greater between the haplotypes that experienced mortality versus haplotypes that all survived than it was between nominal species that all survived. Colonies > 30 cm in diameter were identified as the haplotype experiencing the most mortality, and in 1125 colonies that were not genetically identified, bleaching and mortality increased with colony size. Mortality did not increase with colony size within the haplotype suffering the highest mortality, suggesting that size-dependent bleaching and mortality at the genus level was caused instead by differences among cryptic species. The relative abundance of haplotypes shifted between February and August, driven by declines in the same common haplotype for which mortality was estimated directly, at sites where heat accumulation was greatest, and where larger colony sizes occurred. The identification of morphologically indistinguishable species that differ in their response to thermal stress, but share a similar ecological function in terms of maintaining a coral-dominated state, has important consequences for uncovering response diversity that drives resilience, especially in systems with low or declining functional diversity.
This article revisits the concept of sovereignty in political theory by applying tools adapted from Lacanian psychoanalytic theory. It critically reviews the premises of political subjects assumed by ...sovereignty and formulates a widened concept of sovereignty based on a general understanding of the "self" "self-relation," and "identity" as the fundamental components of sovereignty. With this concept in hand, the article then focuses on the concept of the "Sovereign Good" common to French histories of political thought and of particular interest to Jacques Lacan in his 1959-60 seminar on the Ethics of Psychoanalysis and his 1963 article "Kant with Sade." By reinterpreting the sovereignty of the Sovereign Good, Lacan points to a path according to which an idealized and universalized notion of the sovereign is made possible and energized through an identification of the real with the Sovereign Good. By understanding sovereignty as supported by the Lacanian real, we can better understand both the forces that drive it to self-preservation and the insecurities that make its survival and longevity powerful hindrances to its dissolution
Many e-health technologies are available to promote virtual patient–provider communication outside the context of face-to-face clinical encounters. Current digital communication modalities include ...cell phones, smartphones, interactive voice response, text messages, e-mails, clinic-based interactive video, home-based web-cams, mobile smartphone two-way cameras, personal monitoring devices, kiosks, dashboards, personal health records, web-based portals, social networking sites, secure chat rooms, and on-line forums. Improvements in digital access could drastically diminish the geographical, temporal, and cultural access problems faced by many patients. Conversely, a growing digital divide could create greater access disparities for some populations. As the paradigm of healthcare delivery evolves towards greater reliance on non-encounter-based digital communications between patients and their care teams, it is critical that our theoretical conceptualization of access undergoes a concurrent paradigm shift to make it more relevant for the digital age. The traditional conceptualizations and indicators of access are not well adapted to measure access to health services that are delivered digitally outside the context of face-to-face encounters with providers. This paper provides an overview of digital “encounterless” utilization, discusses the weaknesses of traditional conceptual frameworks of access, presents a new access framework, provides recommendations for how to measure access in the new framework, and discusses future directions for research on access.
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