A suggestion for simplifying the theory of asset prices

Using an ordinal approach to utility, in the spirit of Hicks (1962, 1967a), it is possible to greatly simplify the theory of asset prices. The basic assumption is to summarize any probability distribution into its moments so that preferences over distributions can be mapped into preferences over vectors of moments. This implies that assets, like Lancaster’s (1966) consumption goods, are bundles of characteristics and can be directly priced, at the margin, in terms of the market portfolio. Expected utility is not required and both St.Petersburg and Allais paradoxes may be easily solved

Real Intrest Rate and Growth: An Empirical Note

Are restrictive monetary policies harmful to growth? The note aims at providing some empirical evidence to answer the question. A significant negative correlation between growth and real interest emerges over the period 1960-94; in the eighties this relationship strengthens. This result is in agreement with the traditional view of a long run positive link between growth and capital accumulation and a negative long run link between accumulation and the cost of capital. Moreover the outcome is in line with the view that links the slowdown in economic growth of the industrial countries over the last decades appears to the implementation of restrictive monetary policie

Theta dependence of CP^9 model

We apply to the $CP^9$ model two recently proposed numerical techniques for simulation of systems with a theta term. The algorithms, successfully tested in the strong coupling limit, are applied to the weak coupling region. The results agree and errors have been evaluated and are at % level. The results scale well with the renormalization group equation and show that, for $CP^9$ in presence of a theta term, CP symmetry is spontaneously broken at $\theta=\pi$ in the continuum limit.Comment: 4 pages, 4 figure

Challenges in Acquiring Clinical Simultaneous SPECT-MRI on a PET-MRI Scanner

The INSERT is the world’s first clinical SPECTMRI brain imaging system based on scintillation detectors with a SiPM readout. Here we demonstrate its use within a clinical MRI environment for the first time. Using a standard transmit-receive head coil, and with an appropriate selection of a custom MRI sequence (GRE), we overcome mutual interference. The INSERT and its bulky 50 kg tungsten collimator introduce magnetic field inhomogeneity. Due to the specific MRI-compatible collimator design, inhomogeneity is compensated by shimming, leading to simultaneous acquisition. We process the SPECT data acquired alongside the MRI sequence to evaluate the SPECT system performance and the impact of the MRI. Finally, we present a set of simultaneous SPECT-MRI acquisitions, demonstrating multimodal imaging capabilities, albeit with a limited MRI sequence

COVID-19-associated Guillain-Barré syndrome in the early pandemic experience in Lombardia (Italy)

Objective To estimate the incidence and describe clinical characteristics and outcome of GBS in COVID-19 patients (COVID19-GBS) in one of the most hit regions during the frst pandemic wave, Lombardia. Methods Adult patients admitted to 20 Neurological Units between 1/3–30/4/2020 with COVID19-GBS were included as part of a multi-center study organized by the Italian society of Hospital Neuroscience (SNO). Results Thirty-eight COVID19-GBS patients had a mean age of 60.7 years and male frequency of 86.8%. CSF albuminocytological dissociation was detected in 71.4%, and PCR for SARS-CoV-2 was negative in 19 tested patients. Based on neurophysiology, 81.8% of patients had a diagnosis of AIDP, 12.1% of AMSAN, and 6.1% of AMAN. The course was favorable in 76.3% of patients, stable in 10.5%, while 13.2% worsened, of which 3 died. The estimated occurrence rate in Lombardia ranges from 0.5 to 0.05 GBS cases per 1000 COVID-19 infections depending on whether you consider positive cases or estimated seropositive cases. When we compared GBS cases with the pre-pandemic period, we found a reduction of cases from 165 to 135 cases in the 2-month study period in Lombardia. Conclusions We detected an increased incidence of GBS in COVID-19 patients which can refect a higher risk of GBS in COVID-19 patients and a reduction of GBS events during the pandemic period possibly due to a lower spread of more common respiratory infectious diseases determined by an increased use of preventive measures

The role of immune suppression in COVID-19 hospitalization: clinical and epidemiological trends over three years of SARS-CoV-2 epidemic

Specific immune suppression types have been associated with a greater risk of severe COVID-19 disease and death. We analyzed data from patients >17 years that were hospitalized for COVID-19 at the “Fondazione IRCCS Ca′ Granda Ospedale Maggiore Policlinico” in Milan (Lombardy, Northern Italy). The study included 1727 SARS-CoV-2-positive patients (1,131 males, median age of 65 years) hospitalized between February 2020 and November 2022. Of these, 321 (18.6%, CI: 16.8–20.4%) had at least one condition defining immune suppression. Immune suppressed subjects were more likely to have other co-morbidities (80.4% vs. 69.8%, p < 0.001) and be vaccinated (37% vs. 12.7%, p < 0.001). We evaluated the contribution of immune suppression to hospitalization during the various stages of the epidemic and investigated whether immune suppression contributed to severe outcomes and death, also considering the vaccination status of the patients. The proportion of immune suppressed patients among all hospitalizations (initially stable at <20%) started to increase around December 2021, and remained high (30–50%). This change coincided with an increase in the proportions of older patients and patients with co-morbidities and with a decrease in the proportion of patients with severe outcomes. Vaccinated patients showed a lower proportion of severe outcomes; among non-vaccinated patients, severe outcomes were more common in immune suppressed individuals. Immune suppression was a significant predictor of severe outcomes, after adjusting for age, sex, co-morbidities, period of hospitalization, and vaccination status (OR: 1.64; 95% CI: 1.23–2.19), while vaccination was a protective factor (OR: 0.31; 95% IC: 0.20–0.47). However, after November 2021, differences in disease outcomes between vaccinated and non-vaccinated groups (for both immune suppressed and immune competent subjects) disappeared. Since December 2021, the spread of the less virulent Omicron variant and an overall higher level of induced and/or natural immunity likely contributed to the observed shift in hospitalized patient characteristics. Nonetheless, vaccination against SARS-CoV-2, likely in combination with naturally acquired immunity, effectively reduced severe outcomes in both immune competent (73.9% vs. 48.2%, p < 0.001) and immune suppressed (66.4% vs. 35.2%, p < 0.001) patients, confirming previous observations about the value of the vaccine in preventing serious disease

Dalla crisi finanziaria alla crisi reale

The financial crisis of 2008 is put in relation with two bubbles, financial and housing. Easy credit is at the origin of both bubbles. Risky bonds were issued to mobilize mortgages originated in the housing market, and bad bonds entered a fantastic number of institutional and private portfolios all over the world without any perception of the their risk. Unfortunately, bank credit to speculators was abundant and fed the final growth of the bubbles. When fears started to spread, the fall was immediate and expectations impaired very rapidly. The main aggregate demand components were severely curtailed and production fell as well. This is the crisis of the real economy. Fortunately, as opposed to what happened in 1929, the interventions of central banks and governments have been of an unprecedented size. The bail out of insolvent banks in particular has been providential. The exit from the current crisis, however, will surely be slow

Ordinal utility of moments: foundations and financial behavior

EnAfter Tobin (1958), a considerable effort has been devoted to connecting the expected utility approach to a utility function directly expressed in terms of moments. We follow the alternative route of providing, for the first time, the theoretical, autonomous foundation of an ordinal utility function of moments, representing rational choices under uncertainty, free of any ‘independence axiom’ and compatible with all the behavioral “paradoxes” documented in the economic literature

Handheld Magnetic-Compliant Gamma-Ray Spectrometer for Environmental Monitoring and Scrap Metal Screening

Spotting radioactive material in waste is of paramount importance for environment protection. This is particularly challenging when orphan sources are hidden in scrap metal that shields their activity from the traditional detectors in the portals scanning incoming trucks. In order to address this issue, we present a wireless and compact SiPM-based gamma spectrometer compatible with strong magnetic fields (0.1 T) to be installed in the bore of the lifting electromagnets to scan reduced volumes of metal and thus achieve higher sensitivity. The microcontroller-based instrument provides 11% energy resolution (at 662 keV), an energy range from 60 keV to 1.5 MeV, a max. count rate of 30 kcps, a weight <1 kg, and a power consumption <1 W. The results of its extensive characterization in the laboratory and its validation in the field, including operation in a scrap yard as well as on a drone, are reported

SITH: a 16-channel ASIC for SiPMs Readout in Hadrontherapy Applications

In hadrontherapy treatments, charged particles deposit a high and localized dose in the tumor volume. Detection of secondary radiations like Prompt Gammas (PG) can be used to monitor the dose profile falloff position, increasing the precision of this technique. In this work we present the design of SITH: an ASIC developed for the readout of Silicon Photomultipliers (SiPMs) coupled with scintillators used in this application. PG characteristics set specific requirements for the front-end electronics such as the capability to process up to 5nC input charge (energy up to 8MeV), timing resolution better than 1ns (e.g. for scattering correction), multiple triggering logic and potential for neutron/photon discrimination. We report an overview of the principal electronic stages and simulation results