Incentives through the cycle: microfounded macroprudential regulation

Following a decline in the fundamental risk of assets, the ability of banks to expand the balance sheet under a Value-at-Risk constraint in- creases (as in Adrian and Shin (2010)), boosting the bank’s incentives to provide costly monitoring effort that prevents asset deterioration. On the other hand, high asset demand and prices, eventually, raise the bank’s pay- off in the event of liquidation associated to asset deterioration, jeopardiz- ing incentives. This paper shows that a microprudential regulatory regime that disregards the equilibrium effect of macro variables (asset prices) on micro behavior (effort), performs poorly as low fundamental (exogenous) risk reduces bank’s effort and induces high (endogenous) deterioration risk. This analysis calls for a macroprudential regulatory regime in which the equilibrium feedback effect is fully taken into account by the author- ity in designing incentive compatible capital requirements, providing a theoretical foundation to the countercyclical buffer of Basel III.Macroprudential regulation, financial stability, capital requirement.

Interbank markets and multiplex networks: centrality measures and statistical null models

The interbank market is considered one of the most important channels of contagion. Its network representation, where banks and claims/obligations are represented by nodes and links (respectively), has received a lot of attention in the recent theoretical and empirical literature, for assessing systemic risk and identifying systematically important financial institutions. Different types of links, for example in terms of maturity and collateralization of the claim/obligation, can be established between financial institutions. Therefore a natural representation of the interbank structure which takes into account more features of the market, is a multiplex, where each layer is associated with a type of link. In this paper we review the empirical structure of the multiplex and the theoretical consequences of this representation. We also investigate the betweenness and eigenvector centrality of a bank in the network, comparing its centrality properties across different layers and with Maximum Entropy null models.Comment: To appear in the book "Interconnected Networks", A. Garas e F. Schweitzer (eds.), Springer Complexity Serie

Catheter-based Miniaturized Vision System for Endovascular Applications

New frontiers in research of real-time imaging during endovascular minimally invasive surgery are focusing attention on studies for direct vision of the inner vessel wall, helping catheter tracking and guidance. This master thesis belongs to a European research project, called SCATh (Smart Catheterization), whose primary objective is the creation of an innovative ICT platform for training, pre-operative planning and computer-aided surgical interventions, that closes the existing gap between the reality of the catheter inside the cardiovascular system and the manner in which this reality is presented and made accessible to the interventionalist. The goal of this master thesis is to design and develop a catheter-based optical imaging system that enables intracardiac and intravascular visualization in real time through blood. There are lots of methodologies of cardiovascular imaging which are used to capture detailed real-time information during catheter-based diagnosis and interventions. Advanced techniques in angiography based on X-rays -fluoroscopy- and computed tomography and devices based on ultrasound are typical examples of imaging system for the visualization of blood vessel obtaining also high resolution images. New strategies to have a direct vision through blood would be a disruptive innovation. In fact this catheter-based vision system has the advantage of non ionizing radiation utilization, non total occlusion of vessel and non temporary remotion of blood (opaque in the visible light) from the vision system eld of view. Thus far there are no commercial devices for a direct vision and only two patents deal in vision system with indium gallium arsenide technology and light with wavelengths longer than 1500nm. A drawback to these radiations is the local temperature increase, which provokes hemolysis. We built a prototype of an infrared angioscope for local environment scanning on the catheter tip and for direct vision of inner vessel surface, working with wavelengths where the blood attenuation is minimum and the hemolysis is reduced. In Chapter 1, after a description of the state of art of cardiovascular imaging system technologies, the optical blood properties are analyzed because they affect the image quality. Interaction between blood and electromagnetic spectrum highlights the increasing interest in near infrared angioscopy methodology. In fact moving from the visible region to the infrared one, blood is more transparent and a direct vision through blood is feasible. State of the NIR angioscopes is reported. Chapter 2 presents the design of the infrared vision system, which is made of three main parts: illumination, camera and optics. The lighting source is a custom system which uses LED devices in the 800-1000nm range. Because of the wavelenghts range, a CMOS sensor is suitable for the application and the commercial camera Medigus Introspicio 120 is used. The optical surfaces are developed with the collaboration of the Centro Ricerca Plast-Optica and supported with optical simulations (ASAP optical software). The final system has two visual view fields, allowing the left and right sight of the blood vessel. Each sector has eld of view of 130° horizontal 70° vertical. In Chapter 3 the mechanical design for the integration of all components is developed, obtaining the final structure, which has a cylinder-shape of 8.4mm diameter and 30.0mm height. The system is placed on tip of catheter, which has been developed for insertion inside the vascular system. Chapter 4 reports tests conducted to assess vision system functioning. The first test assesses the penetration distance in air. Subsequently the performances of the system are evaluated when it is dipped into an absorbing medium. Tests have been done in tomato juice and in blood. In Chapter 5 the final conclusions of the development of a near infrared angioscope prototype for endovasculat application are treate

The multiplex structure of interbank networks

The interbank market has a natural multiplex network representation. We employ a unique database of supervisory reports of Italian banks to the Banca d'Italia that includes all bilateral exposures broken down by maturity and by the secured and unsecured nature of the contract. We find that layers have different topological properties and persistence over time. The presence of a link in a layer is not a good predictor of the presence of the same link in other layers. Maximum entropy models reveal different unexpected substructures, such as network motifs, in different layers. Using the total interbank network or focusing on a specific layer as representative of the other layers provides a poor representation of interlinkages in the interbank market and could lead to biased estimation of systemic risk.Comment: 41 pages, 8 figures, 10 table

Incentives through the cycle: microfounded macroprudential regulation

We use an incentive model in which improvements to fundamentals boost the ability of leveraged financial firms (banks) to expand the balance sheet (as in Adrian and Shin 2010). The rise in asset prices due to the amplified response of procyclical systems distorts bankers' incentives in providing (costly and non observable) monitoring effort. On the one hand, the fundamental value of assets positively affects the optimal effort of the banker, thus allowing supervisory authorities to relax incentive-compatible capital requirements and boosting asset demand and prices. On the other hand, in a macro perspective, high prices positively affect the banker's payoff in the bad state of asset liquidation (via asset prices), jeopardizing incentives. This type of externality follows from a purely “macro” phenomenon à la Borio (2003) and should be taken into account by the regulatory authority in designing capital requirements. In procyclical and advanced (low agency costs and highly liquid) financial systems, incentive compatibility requires a higher capital requirement in the face of an improvement to fundamentals. Our results provide a theoretical foundation to the countercyclical buffer provided for by the Basel Committee

Incentives through the cycle: microfounded macroprudential regulation

We use an incentive model in which improvements to fundamentals boost the ability of leveraged financial firms (banks) to expand the balance sheet (as in Adrian and Shin 2010). The rise in asset prices due to the amplified response of procyclical systems distorts bankers' incentives in providing (costly and non observable) monitoring effort. On the one hand, the fundamental value of assets positively affects the optimal effort of the banker, thus allowing supervisory authorities to relax incentive-compatible capital requirements and boosting asset demand and prices. On the other hand, in a macro perspective, high prices positively affect the banker's payoff in the bad state of asset liquidation (via asset prices), jeopardizing incentives. This type of externality follows from a purely “macro” phenomenon à la Borio (2003) and should be taken into account by the regulatory authority in designing capital requirements. In procyclical and advanced (low agency costs and highly liquid) financial systems, incentive compatibility requires a higher capital requirement in the face of an improvement to fundamentals. Our results provide a theoretical foundation to the countercyclical buffer provided for by the Basel Committee.Macroprudential regulation, financial stability, capital requirement.

Mesenchymal stem cells-derived vascular smooth muscle cells release abundant levels of osteoprotegerin

Although several studies have shown that the serum levels of osteoprotegerin (OPG) are significantly elevated in patients affected with atherosclerotic lesions in coronary and peripheral arteries, the cellular source and the role of OPG in the physiopathology of atherosclerosis are not completely defined. Therefore, we aimed to investigate the potential contribution of mesenchymal stem cells in the production/release of OPG. OPG was detectable by immunohistochemistry in aortic and coronary atherosclerotic plaques, within or in proximity of intimal vascular smooth muscle cells (SMC). In addition, bone marrow mesenchymal stem cell (MSC)-derived vascular SMC as well as primary aortic SMC released in the culture supernatant significantly higher levels of OPG with respect to MSC-derived endothelial cells (EC) or primary aortic EC. On the other hand, in vitro exposure to full-length human recombinant OPG significantly increased the proliferation rate of aortic SMC cultures, as monitored by bromodeoxyuridine incorporation. Taken together, these data suggest that OPG acts as an autocrine/paracrine growth factor for vascular SMC, which might contribute to the progression of atherosclerotic lesions

Influence of the type of breastfeeding as a risk or protective factor for the onset of malocclusions: a systematic review

Aim: The correlation between malocclusions in deciduous dentition and type of breastfeeding has been described by many authors in numerous articles. The aim of this article is to investigate the literature about this important topic. Materials: The research was conducted by querying the following databases: PubMed, EBMR, Cochrane Library, Web of Sciences, Medline, Web of Sciences, Ovid and Embase. The key words were: "infant" OR "baby", AND "breastfeeding" AND "malocclusion". As with similar literature review papers, the PRISMA-P (Preferred Reporting Items for Systematic Reviews Protocols) was used. The examined articles were of the following types: randomised controlled trials (RCTs), case-control studies and cohort studies. For the qualitative analysis of the selected studies, it was employed the NOS scale (Newcastle-Ottawa Quality Assessment Scale). Conclusion: Two hundred and fifty articles were selected. After filtering out the articles deemed irrelevant or with obvious bias, only 16 articles were left. From our results, it can be concluded that breastfeeding seems to play a decisive role in preventing the onset of posterior cross-bites and Class II malocclusions, and that this protective effect appears to be time-dependent

TNFSF10 (tumor necrosis factor (ligand) superfamily, member 10)

Review on TNFSF10 (tumor necrosis factor (ligand) superfamily, member 10), with data on DNA, on the protein encoded, and where the gene is implicated

True Giant Posterior Tibial Artery Aneurysm

We report an unusual case of true atherosclerotic posterior tibial artery (PTA) aneurysm without any apparent causative history. To our knowledge, in the English Literature only seven previously cases of true PTA aneurysms are reported. Due to its location, this lesion may require surgical intervention and removal. The presentation, the diagnostic evaluation, and the surgical management of the aneurysm are discussed.</jats:p