Verification of Quantum Computation: An Overview of Existing Approaches

International audienc

An Analysis of Reinsurance and Firm Performance: Evidence from the Taiwan Property-Liability Insurance Industry

[[abstract]]This study investigates the relationship between reinsurance and firm performance by sourcing panel data from the 1999 to 2009 period of the property-liability insurance industry in Taiwan. The results of this investigation offer some insight that firm performance and reinsurance are interdependent. We find that insurers with higher return on assets (ROA) tend to purchase less reinsurance and insurers with higher reinsurance dependence tend to have a lower level of firm performance. Therefore, managers have to strike a balance between decreasing insolvency risk and reducing potential profitability. Other empirical results show that ROA, underwriting risks, liquidity ratio, business line concentration, return on investment (ROI) and financial holding dummy have a significant correlation with reinsurance. In addition, firm size, financial leverage, reinsurance, underwriting risks, liquidity ratio and ROI have a significant influence on firm performance. Our results have practical implications for the property-liability insurance industry and competent authorities in Taiwan.[[incitationindex]]SSCI[[booktype]]紙

Model Systems to Study the Chronic, Polymicrobial Infections in Cystic Fibrosis: Current Approaches and Exploring Future Directions

A recent workshop titled “Developing Models to Study Polymicrobial Infections,” sponsored by the Dartmouth Cystic Fibrosis Center (DartCF), explored the development of new models to study the polymicrobial infections associated with the airways of persons with cystic fibrosis (CF). The workshop gathered 351 investigators over two virtual sessions. Here, we present the findings of this workshop, summarize some of the challenges involved with developing such models, and suggest three frameworks to tackle this complex problem. The frameworks proposed here, we believe, could be generally useful in developing new model systems for other infectious diseases. Developing and validating new approaches to study the complex polymicrobial communities in the CF airway could open windows to new therapeutics to treat these recalcitrant infections, as well as uncovering organizing principles applicable to chronic polymicrobial infections more generally

Fine-scale appendage structure of the Cambrian trilobitomorph Naraoia spinosa and its ontogenetic and ecological implications

Trilobitomorphs are a species-rich Palaeozoic arthropod assemblage that unites trilobites with several other lineages that share similar appendage structure. Post-embryonic development of the exoskeleton is well documented for some trilobitomorphs, especially trilobites, but little is known of the ontogeny of their soft parts, limiting understanding of their autecology. Here, we document appendage structure of the Cambrian naraoiid trilobitomorph Naraoia spinosa by computed microtomography, resulting in three-dimensional reconstructions of appendages at both juvenile and adult stages. The adult has dense, strong spines on the protopods of post-antennal appendages, implying a predatory/scavenging behaviour. The absence of such gnathobasic structures, but instead tiny protopodal bristles and a number of endopodal setae, suggests a detritus-feeding strategy for the juvenile. Our data add strong morphological evidence for ecological niche shifting by Cambrian arthropods during their life cycles. A conserved number of appendages across the sampled developmental stages demonstrates that Naraoia ceased budding off new appendages by the mid-juvenile stage.© 2019 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited. The attached file is the published pdf

The Impact of Mortgage-Backed Securities on Capital Requirements of Life Insurers in the Financial Crisis of 2007–2008

In this paper, we explore U.S. life insurers’ exposure to mortgage backed securities (MBS) and its potential impact on capital should the credit ratings of these bonds be lowered. We analyse 2 years: 2003 (well before the realisation of problems with these instruments) and 2006 (immediately prior). We create five potential scenarios of different severity for recategorising MBS credit ratings and compute the theoretical impact on measured insurer asset risk, via a proxy for the C-1 component of life insurers’ risk-based capital. Under all scenarios, we find large increases in assessed asset risk. We then model insurer capital structure as a function of asset risk and other factors to assess whether insurers had prepared their capital structures for the possibility of problems with these instruments. Our findings indicate not only that insurers were unprepared for MBS downgrades, but also that they reduced capital as they accumulated MBS, as though acquiring MBS should raise the overall quality of the investment portfolio. Finally, we analyse possible adjustments to capital to accommodate the now recognised increased risks of MBS. Our models suggest, for example, that an insurer with median residential MBS exposure might be expected to increase its capital by 10 per cent or more to maintain a historical relationship between capital and risk factors, in the event of a moderate recategorisation of MBS risk. Even larger adjustments are indicated should the crisis spread to commercial MBS as well. The Geneva Papers (2009) 34, 100–118. doi:10.1057/gpp.2008.40