A Market Risk Approach to Liquidity Risk and Financial Contagion

According to traditional literature, liquidity risk in individual banks can turn into a system-wide ¯nancial crisis when either interbank credit exposures or bank runs are present. This paper shows that this phenomenon can also arise when individual liquidity risk trans- forms into system-wide market risk (even in the absence of bank runs and interbank credit networks). This happens when banks try to sell some portion of its assets in order to overcome a liquidity shortage (individual liquidity risk). These sales depress the market price of assets if demand is not perfectly elastic. Given the fact that banks mark to market the asset book, the fall of market price reduces the value of assets of every bank in the system (system-wide market risk), leaving them less suited for future liquidity shortages and therefore more prone to bankruptcies. The paper rationalizes this idea through the simulation of a model that tries to capture the behavior of a liq- uidity manager that faces shocks on bank deposits and loans. The main results suggest that the extent of ¯nancial contagion depends crucially on the size of the market for assets.liquidity manager, liquidity risk, market risk, systemic risk, financial contagion, mark-to-market

Prediction and near-field observation of skull-guided acoustic waves

Ultrasound waves propagating in water or soft biological tissue are strongly reflected when encountering the skull, which limits the use of ultrasound-based techniques in transcranial imaging and therapeutic applications. Current knowledge on the acoustic properties of the cranial bone is restricted to far-field observations, leaving its near-field properties unexplored. We report on the existence of skull-guided acoustic waves, which was herein confirmed by near-field measurements of optoacoustically-induced responses in ex-vivo murine skulls immersed in water. Dispersion of the guided waves was found to reasonably agree with the prediction of a multilayered flat plate model. It is generally anticipated that our findings may facilitate and broaden the application of ultrasound-mediated techniques in brain diagnostics and therapy.Comment: 7 pages, 5 figures, appendix with 2 figure

Simultaneous control of volumetric light distribution through turbid media using real-time three-dimensional optoacoustic feedback

Focusing light through turbid media presents a highly fascinating challenge in modern biophotonics. The unique capability of optoacoustics for high resolution imaging of light absorption contrast in deep tissues can provide a natural and efficient feedback to control light delivery in scattering medium. While basic feasibility of using optoacoustic readings as a feedback mechanism for wavefront shaping has been recently reported, the suggested approaches may require long acquisition times making them challenging to be translated into realistic tissue environments. In an attempt to significantly accelerate dynamic wavefront shaping capabilities, we present here a feedback-based approach using real-time three-dimensional optoacoustic imaging assisted with genetic-algorithm-based optimization. The new technique offers robust performance in the presence of noisy measurements and can simultaneously control the scattered wave field in an entire volumetric region.Comment: 4 pages, 3 figure

Human Supremacy as Posthuman Risk

Human supremacy is the widely held view that human interests ought to be privileged over other interests as a matter of public policy. Posthumanism is an historical and cultural situation characterized by a critical reevaluation of anthropocentrist theory and practice. This paper draws on Rosi Braidotti’s critical posthumanism and the critique of ideal theory in Charles Mills and Serene Khader to address the use of human supremacist rhetoric in AI ethics and policy discussions, particularly in the work of Joanna Bryson. This analysis leads to identifying a set of risks posed by human supremacist policy in a posthuman context, specifically involving the classification of agents by type