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A geometric Berry phase angle induced in <i>Im-3m</i> H<sub>3</sub>S at 200 GPa by ultra-fast laser pulses
No full textWe investigated Im-3m H3S at 200 GPa, a pressure regime where crystalline H3S is widely considered to be a superconductor. Simulated circularly polarized 10 femtosecond (fs) laser pulses were applied and we quantified the effects on the electron dynamics both during the application of the ultra-fast laser pulse and 5.0 fs after the pulse was switched off. In addition, the carrier-envelope phase (CEP) angle ϕ, which quantifies the relationship between the time-varying direction of electric (E)-field and the amplitude envelope, is employed to control the time evolution of the wavefunction ψ(r). This is undertaken for the first application of Next Generation Quantum Theory of Atoms in Molecules (NG-QTAIM) to the solid state. Ultra-fast phenomena related to superconductivity are discovered in the form of a geometric Berry phase angle associated with the H--H bonding in addition to very high values of the chirality–helicity function that correspond to values normally found in chiral molecules. Future applications are discussed, including chiral spin selective phenomena in addition to high-temperature superconductivity and organic superconductors where phonons do not play a significant role
Sensorimotor adaptation reveals systematic biases in 3D perception
No full textThe existence of biases in visual perception and their impact on visually guided actions has long been a fundamental yet unresolved question. Evidence revealing perceptual or visuomotor biases has typically been disregarded because such biases in spatial judgments can often be attributed to experimental measurement confounds. To resolve this controversy, we leveraged the visuomotor system’s adaptation mechanism — triggered only by a discrepancy between visual estimates and sensory feedback — to directly indicate whether systematic errors in perceptual and visuomotor spatial judgments exist. To resolve this controversy, we leveraged the adaptive mechanisms of the visuomotor system to directly reveal whether systematic biases or errors in perceptual and visuomotor spatial judgments exist. In a within-subject study (N=24), participants grasped a virtual 3D object with varying numbers of depth cues (single vs. multiple) while receiving haptic feedback. The resulting visuomotor adaptations and aftereffects demonstrated that the planned grip size, determined by the visually perceived depth of the object, was consistently overestimated. This overestimation intensified when multiple cues were present, despite no actual change in physical depth. These findings conclusively confirm the presence of inherent biases in visual estimates for both perception and action, and highlight the potential use of visuomotor adaptation as a novel tool for understanding perceptual biases
DNA sensing with whispering gallery mode microlasers
No full textNucleic acid sensing is crucial for advancing diagnostics, therapeutic monitoring, and molecular biology research by enabling the precise identification of DNA and RNA interactions. Here, we present an innovative sensing platform based on DNA-functionalized whispering gallery mode (WGM) microlasers. By correlating spectral shifts in laser emission to changes in the refractive index, we demonstrate real-time detection of DNA hybridization and structural changes. The addition of gold nanoparticles to the DNA strands significantly enhances sensitivity, and exclusively labeling the sensing strand or a hairpin strand eliminates the need for secondary labeling of the target strand. We further show that ionic strength influences DNA compactness, and we introduce a hairpin-based system as a dual-purpose sensor and controlled release mechanism for drug delivery. This versatile WGM-based platform offers promise for sequence-specific nucleic acid sensing, multiplexed detection, and in vivo applications in diagnostics and cellular research
Building a shared perspective on Hesketh Out Marsh through co-production
No full textThis report summarises the process and outputs of a workshop organised and funded via the Co-Opt research project and hosted by Hesketh Bank Community Centre on the 6th of June 2024. The workshop brought together participants who are interested and/or affected by the Hesketh Out Marsh managed realignment, including representatives of government agencies, local government, farmers and nature conservation charities.The objective of the workshop and of this report is to build a shared understanding of the current challenges at Hesketh Out Marsh and the surrounding area and outline the steps required to address them. This workshop served as a starting point for a collaborative and innovative approach to decision-making for this area. Diverse, and sometimes contrasting, views exist about the success and effectiveness of this managed realignment scheme. A participatory approach (co-production) was therefore adopted to foster a shared understanding of the social-ecological challenges in the area. This participatory process, which values equal contributions from all participants, highlights the importance of co-creation in decision-making and coastal management.This report seeks to gather and present the diverse perspectives of the participants. An initial draft was prepared and shared with participants for their feedback, which was subsequently collected and incorporated into the final version. We made every effort to include all the feedback received and believe that we have addressed the most significant points.The main issues related to Hesketh Out Marsh were highlighted to be fragmented responsibilities in terms of maintenance and the siltation of outfalls. The area is under pressure due to constraints on the drainage system and a lack of funding. Participants identified many potential responses and preparatory measures, highlighting improved strategic planning, public engagement and stakeholder collaboration as some of the essential future actions.This report focuses on Hesketh Out Marsh but is designed to function as a standalone document for wide distribution. It also serves as an example of a participatory process that can be adapted for local decision-making in other contexts
Violence as a constitutive of states
No full textIs the state monopoly on the use of legitimate violence a modern invention that refers exclusively to a particular provincial sociohistorical phenomenon that emerged in seventeenth-century Europe? The answer this paper presents is no. Instead, I argue that the canonical Eurocentric epistemic communities have sought to displace other systems of governance and administration and replace them with European and Westphalian-like models. Yet, an urgent question remains unanswered: Why were political scientists and political sociology scholars from the Global South forced to adopt these [Eurocentric] theses and apply them to other, diverse regions, which have had different and prior historical, social, political, cultural, and economic experiences from Europe? To answer these questions, the paper adopts a decolonial approach to examine the following hypothesis: internal violence, repression, and control (from above) were the constitutive factors of forming and preserving political authority necessary for the establishment and development of modern states outside the Western hemisphere. To do so, ʿAbd al-Raḥmān Ibn Ḵẖaldūn’s (1332–1406) theses on the ontological and constitutive role of violence are deployed to critique the Weberian principle of the state’s monopoly over the legitimate use of physical force. I present what I call the Ḵẖaldūnian trilogy of ʿasabiyya, al-Daʿwa al-Diīniyah, al-shāwkāh wa al-ghālbāh wa al-qāhr (i.e., the dominant group, religious-ideological discourse, force majeure, and repression-domination), upon which state/authority relies to constitute and consolidate its power and legitimacy, without being occupied with either the legality or the justice of this violence, as epistemic alternative of the Eurocentric conceptions of state-building
Are treatment services ready for the use of big data analytics and artificial intelligence in managing opioid use disorder?
No full textIn this viewpoint, we explore the use of big data analytics and artificial intelligence (AI) and discuss important challenges to their ethical, effective, and equitable use within opioid use disorder (OUD) treatment settings. Applying our collective experiences as OUD policy and treatment experts, we discuss 8 key challenges that OUD treatment services must contend with to make the most of these rapidly evolving technologies: data and algorithmic transparency, clinical validation, new practitioner-technology interfaces, capturing data relevant to improving patient care, understanding and responding to algorithmic outputs, obtaining informed patient consent, navigating mistrust, and addressing digital exclusion and bias. Through this paper, we hope to critically engage clinicians and policy makers on important ethical considerations, clinical implications, and implementation challenges involved in big data analytics and AI deployment in OUD treatment settings
The refugee political in the age of imperial crisis, decolonization, and cold war, 1930s–1950s
No full textThe three decades spanning the 1930s, '40s, and '50s witnessed the birth of the modern global state system, characterized by a protracted and tortuous transition from a world of empires to a world of nation-states. The demise of Nazi, British, and Japanese empires emancipated millions of people across the world. However, as old empires dissolved, new post-imperial states continued older colonial-origin forms of ethno-religious discrimination and ruling-class dominance, or invented novel hierarchies. Hence, this epoch was marked by catastrophic outbursts of racial violence, sectarian war, and genocide. If majoritarian nation-states were the privileged offspring of this transformation, then refugees were the unwanted issue. The national citizen and the refugee were co-created. Against their forced displacement and subalternization, refugees re-politicized their selves. We define this as ‘the refugee political’: refugees constructing themselves as political beings and building wide-ranging alliances – with churches, politicians, and entrepreneurs; with peasants, industrial workers, and feminists. They became ‘subaltern internationalists’, linking the Dachen Islands to the United States, and maritime Southeast Asia to India; connecting central European Jews to Australian women, or impoverished Indians to Soviet and Chinese communists. They created new forms of ‘refugee polis’ – political communities which were simultaneously local and daringly transnational
