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Probing progression of heating through the lower flare atmosphere via high-cadence IRIS spectroscopy
No full textRecent high-cadence flare campaigns by the Interface Region Imaging Spectrograph (IRIS) have offered new opportunities to study rapid processes characteristic of flare energy release, transport, and deposition. Here, we examine high-cadence chromospheric and transition region spectra acquired by IRIS during a C-class flare from 2022 September 25. Within the flare ribbon, the intensities of the Si ɪᴠ 1402.77 Å, C ɪɪ 1334.53 Å and Mg ɪɪ k 2796.35 Å lines peaked at different times, with the transition region Si ɪᴠ typically peaking before the chromospheric Mg ɪɪ line by 1–6 s. To understand the nature of these delays, we probed a grid of radiative hydrodynamic flare simulations heated by electron beams, thermal conduction-only, or Alfvén waves. Electron beam parameters were constrained by hard X-ray observations from the Gamma-ray Burst Monitor (GBM) onboard the Fermi spacecraft. Reproducing light curves where Si ɪᴠ peaks precede those in Mg ɪɪ proved to be a challenge because only a subset of Fermi/GBM-constrained electron beam models were consistent with the observations. Light curves with relative timings consistent with the observations were found in simulations heated by either high-flux electron beams or by Alfvén waves, while the thermal conduction heating does not replicate the observed delays. Our analysis shows how delays between chromospheric and transition region emission pose tight constraints on flare models and properties of energy transport, highlighting the importance of obtaining very high-cadence data sets with IRIS and other observatories
Emotions in violent extremism
No full textThis chapter examines how emotions contribute to the development of violent extremism, drawing on research into emotional drivers of violent intergroup behavior. We first introduce the concept of emotion and explain the role of cognitive appraisals of events in shaping emotions. Then, to position emotions within the context of hostile intergroup relations, we demonstrate how social identities and group processes impact emotional experience. In the main section of this chapter, we consider the roles of several discrete emotions that motivate distinct types of behaviors relevant to violent extremism. Using a broad framework of the radicalization process, we suggest that: (1) Humiliation, shame, and anger in response to self- or group-relevant experiences are pertinent pre-radicalization as they create a desire to re-establish a positive self- or group-image and to restore a sense of justice; (2) Contempt, disgust, and hatred, as emotions that exclude their targets from moral consideration and motivate their eradication, develop during active radicalization; and (3) Positive emotions, such as love, joy and pride, which increase commitment and motivate others, characterize the engagement stage. We draw out implications of our analysis for policy makers, stressing the importance of responding to the unfulfilled emotional needs that motivate violent extremism
Klaus Ridder and Hans-Joachim Ziegeler, eds., <i>Deutsche Versnovellistik des 13. bis 15. Jahrhunderts (DVN)</i>
No full textMany-body open quantum systems
No full textThese lecture notes discuss the recent theoretical advances in the understanding of open quantum many-body physics in platforms where both dissipative and coherent processes can be tuned and controlled to a high degree. We start by reviewing the theoretical frameworks and methods used to describe and tackle open quantum many-body systems. We then discuss the use of dissipative processes to engineer many-body stationary states with desired properties and the emergence of dissipative phase transitions arising out of the competition between coherent evolution and dissipation. We review the dynamics of open quantum many body systems in the presence of correlated many-body dissipative processes, such as heating and many-body losses. Finally we provide a different perspective on open quantum many-body systems by looking at stochastic quantum trajectories, relevant for the case in which the environment represents a monitoring device, and the associated measurement-induced phase transitions
Imitating God ‘clothed in glory’:a voluntarist reading of Malebranche’s natural and political legislation
No full textBuilding on previous research into the ‘politicization’ or ‘theological-political analogy’ of Nicolas Malebranche, this paper seeks to uncover the dimensions of voluntarism – particularly political voluntarism – within his philosophy and their compatibility with theories of absolute sovereignty in seventeenth-century Europe. These dimensions are often obscured by Malebranche’s seemingly unwavering intellectualist stance. This study challenges Frank’s Augustinian interpretation, which argues that Malebranche’s moral order precludes a self-consistent ‘Schmittian’ secularization. Instead, it demonstrates that Malebranche conceived secular sovereignty as an exclusive imitation of God’s omnipotence, employing a voluntarist framework to account for both natural and political obedience. Through comparative analysis, it is argued that, despite the eternity and immutability of moral principles, Malebranche’s rejection of the Cartesian conflation of reason and will – combined with his emphasis on the contingency of God’s choices – imbued his natural laws with a metaphysical and epistemological voluntarist structure. Moreover, regarding the monopoly over interpretation and the selective realization of moral principles, Malebranche’s political legislation mirrored a voluntarist and ‘absolutist’ framework akin to his conception of natural law. By disentangling irresistible power from an irreproachable yet essentially incomprehensible reason, Malebranche appropriated the concept of ‘sovereignty’ from his contemporary political thought and applied it to both theology and human politics
Investigating the contribution of socioeconomic position to ethnic inequalities in severe COVID-19 outcomes:population-based mediation analyses of national linked Scottish data
No full textWe quantified the extent to which socio-economic position (SEP) contributed to ethnic inequalities in severe COVID-19 outcomes (hospitalization or death) in Scotland. We used linked 2011 Scottish Census and health records to assess whether ethnic inequalities were mediated by different SEP measures: area deprivation, educational status, household composition, and multigenerational household. We considered disaggregated ethnicities ‘White Scottish’, ‘White British or Irish’, ‘Other White’, ‘South Asian’, ‘African, Caribbean, or Black’, and ‘Other’. We applied marginal structural models to estimate causal pathways. Of the 3 297 205 individuals analysed, 38 213 (1.2%) had severe COVID-19 outcomes. South Asians had elevated risk of severe COVID-19 compared to White Scottish (hazard ratio: 1.7; 95% confidence interval: 1.5–1.9), while White British or Irish (hazard ratio: 0.7; confidence interval: 0.6–08) and other White (hazard ratio: 0.8; confidence interval: 0.7–0.9) had reduced risk. When holding area deprivation constant, the risk of severe COVID-19 declined by 16.5% for South Asians and 49.2% for White British or Irish; but increased for other White (75.4%). When holding education constant, the risk of severe COVID-19 reduced by 24.8% for White British or Irish and 20.6% for other White; but increased by 74.6% for South Asians. Only a slight change in risk was observed for the South Asians after holding household size and multigenerational household constant. Risk estimates for African, Caribbean or Black, and other groups were underpowered. SEP measures differed substantially in the extent to which they mediated ethnic inequalities in severe COVID-19. This highlights the necessity of addressing multiple dimensions of SEP that drive ethnic inequalities
Spirobisindane-based hole transporting materials for conventional and indoor halide perovskite solar cells
No full textHole transporting materials (HTMs) are a vital component for both conventional and indoor perovskite solar cells. Spiro-OMeTAD has become one of the most widely studied HTM; however, its high molecular symmetry tends to give rise to nonuniform films that are not conducive to good photovoltaic device stability and large-area processing. Moreover, other issues relating to Spiro-OMeTAD, such as high cost, have spurred investigations into the development of new HTMs. Here, we report two spirobisindane-based HTMs (AS-135 and AS-179) for conventional and indoor perovskite solar cells. The lower symmetry and ability to synthesize from cheap, readily accessible precursors provides obvious advantages over Spiro-OMeTAD. We show that spirobisindane-based HTMs are effective HTMs under both 1 Sun and indoor illumination upon doping with LiTFSi and power conversion efficiency ≈11% were demonstrated under 1 Sun and over 20% under 1000 lx indoor illuminance
Rituals, rivers and the Romans:deconstructing the significance of rivers in Roman Britain
No full textForeword:theology in conversation
No full textForeword to the conference volume on Christoph Schwöbel's theology as "theology in conversation" which took place in St Andrews 2023 as part of the annual meeting of the European Academy of Religion
