A simple model of trading and pricing risky assets under ambiguity: any lessons for policy-makers?

The 2007-2008 financial crises has made it painfully obvious that markets may quickly turn illiquid. Moreover, recent experience has taught us that distress and lack of active trading can jump "around" between seemingly unconnected parts of the financial system contributing to transforming isolated shocks into systemic panic attacks. We develop a simple two-period model populated by both standard expected utility maximizers and by ambiguity-averse investors that trade in the market for a risky asset. We show that, provided there is a sufficient amount of ambiguity, market break-downs where large portions of traders withdraw from trading are endogenous and may be triggered by modest re-assessments of the range of possible scenarios on the performance of individual securities. Risk premia (spreads) increase with the proportion of traders in the market who are averse to ambiguity. When we analyze the effect of policy actions, we find that when a market has fallen into a state of impaired liquidity, bringing the market back to orderly functioning through a reduction in the amount of perceived ambiguity may cause further reductions in equilibrium prices. Finally, our model provides stark indications against the idea that policy makers may be able to "inflate" their way out of a financial crisis.Risk ; Capital assets pricing model ; Financial crises ; Federal Reserve System

Ambiguity in asset pricing and portfolio choice: a review of the literature

A growing body of empirical evidence suggests that investors’ behavior is not well described by the traditional paradigm of (subjective) expected utility maximization under rational expectations. A literature has arisen that models agents whose choices are consistent with models that are less restrictive than the standard subjective expected utility framework. In this paper we conduct a survey of the existing literature that has explored the implications of decision-making under ambiguity for financial market outcomes, such as portfolio choice and equilibrium asset prices. We conclude that the ambiguity literature has led to a number of significant advances in our ability to rationalize empirical features of asset returns and portfolio decisions, such as the empirical failure of the two-fund separation theorem in portfolio decisions, the modest exposure to risky securities observed for a majority of investors, the home equity preference in international portfolio diversification, the excess volatility of asset returns, the equity premium and the risk-free rate puzzles, and the occurrence of trading break-downs.Capital assets pricing model ; Investments

Endothelin-1 Drives Epithelial-Mesenchymal Transition In Hypertensive Nephroangiosclerosis

BACKGROUND: Tubulointerstitial fibrosis, the final outcome of most kidney diseases, involves activation of epithelial mesenchymal transition (EMT). Endothelin‐1 (ET‐1) activates EMT in cancer cells, but it is not known whether it drives EMT in the kidney. We therefore tested the hypothesis that tubulointerstitial fibrosis involves EMT driven by ET‐1. METHODS AND RESULTS: Transgenic TG[mRen2]27 (TGRen2) rats developing fulminant angiotensin II–dependent hypertension with prominent cardiovascular and renal damage were submitted to drug treatments targeted to ET‐1 and/or angiotensin II receptor or left untreated (controls). Expressional changes of E‐cadherin and α‐smooth muscle actin (αSMA) were examined as markers of renal EMT. In human kidney HK‐2 proximal tubular cells expressing the ET(B) receptor subtype, the effects of ET‐1 with or without ET‐1 antagonists were also investigated. The occurrence of renal fibrosis was associated with EMT in control TGRen2 rats, as evidenced by decreased E‐cadherin and increased αSMA expression. Irbesartan and the mixed ET‐1 receptor antagonist bosentan prevented these changes in a blood pressure–independent fashion (P < 0.001 for both versus controls). In HK‐2 cells ET‐1 blunted E‐cadherin expression, increased αSMA expression (both P < 0.01), collagen synthesis, and metalloproteinase activity (P < 0.005, all versus untreated cells). All changes were prevented by the selective ET(B) receptor antagonist BQ‐788. Evidence for involvement of the Rho‐kinase signaling pathway and dephosphorylation of Yes‐associated protein in EMT was also found. CONCLUSIONS: In angiotensin II–dependent hypertension, ET‐1 acting via ET(B) receptors and the Rho‐kinase and Yes‐associated protein induces EMT and thereby renal fibrosis

Online Banking Satisfaction in Italy - OBS project

The datasets provide information from a questionnaire that investigated customer satisfaction of some online banking services in Italy in May and September 2015

Connections at height: skybridges

Gli skybridges, diffusisi negli ultimi vent’anni nelle città a sviluppo verticale, rappresentano una modalità di collegamento in quota tra edifici di grande altezza e costituiscono oggi una vera e propria infrastruttura urbana, essendo in grado di connettere più edifici e intere parti di città. I ponti aerei hanno un ulteriore e importante ruolo nel garantire la sicurezza dei grattacieli, consentendo la possibilità di una evacuazione orizzontale in caso di esodo come alternativa a quello solo verticale. Il contributo propone una disanima di queste strutture, con una lettura finalizzata a comprenderne il funzionamento, le potenzialità architettoniche e urbane, e le possibili evoluzioni per la città contemporanea

Koszul complexes and relative homological algebra of functors over posets

Under certain conditions, Koszul complexes can be used to calculate relative Betti diagrams of vector space-valued functors indexed by a poset, without the explicit computation of global minimal relative resolutions. In relative homological algebra of such functors, free functors are replaced by an arbitrary family of functors. Relative Betti diagrams encode the multiplicities of these functors in minimal relative resolutions. In this article we provide conditions under which grading the chosen family of functors leads to explicit Koszul complexes whose homology dimensions are the relative Betti diagrams, thus giving a scheme for the computation of these numerical descriptors

Case Report: Microangiopathic Hemolytic Anemia With Normal ADAMTS13 Activity

Thrombotic microangiopathies (TMAs) include a heterogeneous group of diseases characterized by abnormalities in the vessel walls of arterioles and capillaries resulting in microvascular thrombosis that typically presents with a microangiopathic hemolytic anemia (MAHA) and severe thrombocytopenia. We describe here the case of an 82-year-old woman, who came to our attention for a clinical condition consistent with thrombotic microangiopathy. Even if initially highly suggestive for a thrombotic thrombocytopenic purpura (TTP), the elevated ADAMTS13 activity together with the alteration of the main coagulation parameters (D-dimer elevation, fibrinogen consumption, slightly prolonged prothrombin time), induced us to consider several other diseases in the differential diagnostic process. The case evolved toward a suspected overlapped secondary hemophagocytic syndrome, though the hyperferritinemia was finally interpreted within the frame of a cytokine storm. After a complex diagnostic workup, the clinical and biochemical parameters guided us toward the diagnosis of a cancer-related microangiopathic hemolytic anemia (CR-MAHA) secondary to a relapsing breast cancer with multiple metastatic localizations. Prednisone 1 mg/kg body weight was started, and several units of fresh frozen plasma were infused, obtaining a good control of the hemolysis. No specific oncological therapies were, however, possible, due to the older age and the critically compromised general condition of the patient; therefore, after clinical stabilization, the patient was discharged for treatment in a palliative care Hospital

En Face Optical Coherence Tomography to Detect and Measure Geographic Atrophy

Citation: Pilotto E, Guidolin F, Convento E, et al. En face optical coherence tomography to detect and measure geographic atrophy. Invest Ophthalmol Vis Sci. 2015;56:8120-8124. DOI:10.1167/iovs.15-17366 PURPOSE. To detect and quantify geographic atrophy (GA) secondary to age-related macular degeneration using en face optical coherence tomography (OCT) and to correlate it to GA measured with fundus autofluorescence (FAF). METHODS. Twenty-four consecutive patients (27 eyes) were studied with both standard (STD)-and enhanced depth imaging (EDI)-OCT. En face OCT images were obtained at the outer retinal layer (OR) and at the choroidal layer (CH) level for both STD-and EDI-OCT. Areas of GA were measured on the en face OCT images and were correlated with the GA areas measured on blue (B)-and near infrared (NIR)-wavelength FAF images. CONCLUSIONS. En face OCT is a reliable method to detect and quantify GA, particularly when analyzed at the OR level, where the photoreceptors&apos; loss creates an abrupt transition in OCT reflectivity. RESULTS. The intraoperator agreement i

sustainable and resilient building design: approaches, methods and tools

The challenges to which contemporary building design needs to respond grow steadily. They originate from the influence of changing environmental conditions on buildings, as well as from the need to reduce the impact of buildings on the environment. The increasing complexity requires the continual revision of design principles and their harmonisation with current scientific findings, technological development, and environmental, social, and economic factors. It is precisely these issues that form the backbone of the thematic book, Sustainable and Resilient Building Design: Approaches, Methods, and Tools. The purpose of this book is to present ongoing research from the universities involved in the project Creating the Network of Knowledge Labs for Sustainable and Resilient Environments (KLABS). The book starts with the exploration of the origin, development, and the state-of-the-art notions of environmental design and resource efficiency. Subsequently, climate change complexity and dynamics are studied, and the design strategy for climate-proof buildings is articulated. The investigation into the resilience of buildings is further deepened by examining a case study of fire protection. The book then investigates interrelations between sustainable and resilient building design, compares their key postulates and objectives, and searches for the possibilities of their integration into an outreaching approach. The fifth article in the book deals with potentials and constraints in relation to the assessment of the sustainability (and resilience) of buildings. It critically analyses different existing building certification models, their development paths, systems, and processes, and compares them with the general objectives of building ratings. The subsequent paper outlines the basis and the meaning of the risk and its management system, and provides an overview of different visual, auxiliary, and statistical risk assessment methods and tools. Following the studies of the meanings of sustainable and resilient buildings, the book focuses on the aspects of building components and materials. Here, the life cycle assessment (LCA) method for quantifying the environmental impact of building products is introduced and analysed in detail, followed by a comprehensive comparative overview of the LCA-based software and databases that enable both individual assessment and the comparison of different design alternatives. The impact of climate and pollution on the resilience of building materials is analysed using the examples of stone, wood, concrete, and ceramic materials. Accordingly, the contribution of traditional and alternative building materials to the reduction of negative environmental impact is discussed and depicted through different examples. The book subsequently addresses existing building stock, in which environmental, social, and economic benefits of building refurbishment are outlined by different case studies. Further on, a method for the upgrade of existing buildings, described as ‘integrated rehabilitation’, is deliberated and supported by best practice examples of exoskeleton architectural prosthesis. The final paper reflects on the principles of regenerative design, reveals the significance of biological entities, and recognises the need to assign to buildings and their elements a more advanced role towards natural systems in human environments