The weather derivatives market: modelling and pricing temperature

The main objective of the thesis is to find a pricing model for weather derivatives based on temperature. A general Ornstein-Uhlenbeck process with seasonal mean and volatility is proposed to model the time-dynamics of daily average temperatures. The model is fitted to almost 54 years of daily observations recorded in Chicago, Philadelphia, Portland and Tucson. The unequivocal evidence of fat tails and negative skewness observed for the city of Tucson is modelled by introducing Lèvy processes. Since weather derivatives is an incomplete market, unique prices are derived using the market price of risk. Finally, an estimate of the market price of risk is provided by calibrating theoretical prices to the actual quoted market prices

On coalescence as the origin of nuclei in hadronic collisions

The origin of weakly-bound nuclear clusters in hadronic collisions is a key question to be addressed by heavy-ion collision (HIC) experiments. The measured yields of clusters are approximately consistent with expectations from phenomenological statistical hadronisation models (SHMs), but a theoretical understanding of the dynamics of cluster formation prior to kinetic freeze out is lacking. The competing model is nuclear coalescence, which attributes cluster formation to the effect of final state interactions (FSI) during the propagation of the nuclei from kinetic freeze out to the observer. This phenomenon is closely related to the effect of FSI in imprinting femtoscopic correlations between continuum pairs of particles at small relative momentum difference. We give a concise theoretical derivation of the coalescence--correlation relation, predicting nuclear cluster spectra from femtoscopic measurements. We review the fact that coalescence derives from a relativistic Bethe-Salpeter equation, and recall how effective quantum mechanics controls the dynamics of cluster particles that are nonrelativistic in the cluster centre of mass frame. We demonstrate that the coalescence--correlation relation is roughly consistent with the observed cluster spectra in systems ranging from PbPb to pPb and pp collisions. Paying special attention to nuclear wave functions, we derive the coalescence prediction for hypertriton and show that it, too, is roughly consistent with the data. Our work motivates a combined experimental programme addressing femtoscopy and cluster production under a unified framework. Upcoming pp, pPb and peripheral PbPb data analysed within such a programme could stringently test coalescence as the origin of clusters.Comment: 24 pages, 10 figure

Unitn-eprints: risultati di utilizzo, prospettive di sviluppo

The digital institutional archive Unitn-eprints, containing reserach outputs by the academic community of the University of Trento, was born in 2002. In this paper we analyze the software customization, some usage results and statistics, and its future perspectives and developments in connection with research evaluation systems

Unitn-eprints: risultati di utilizzo, prospettive di sviluppo

The digital institutional archive Unitn-eprints, containing reserach outputs by the academic community of the University of Trento, was born in 2002. In this paper we analyze the software customization, some usage results and statistics, and its future perspectives and developments in connection with research evaluation systems

Gait and Equilibrium in Subcortical Vascular Dementia

Subcortical vascular dementia is a clinical entity, widespread, even challenging to diagnose and correctly treat. Patients with this diagnosis are old, frail, often with concomitant pathologies, and therefore, with many drugs in therapy. We tried to diagnose and follow up for three years more than 600 patients. Study subjects were men and women, not bedridden, aged 68–94 years, outpatients, recruited from June, 1st 2007 to June, 1st 2010. We examined them clinically, neurologically, with specific consideration on drug therapies. Our aim has been to define gait and imbalance problem, if eventually coexistent with the pathology of white matter and/or with the worsening of the deterioration. Drug intake interference has been detected and considered

Hypotension in Subcortical Vascular Dementia, a New Risk Factor – Wasn’t It Hypertension?

Age \u2013related cerebral degenerative changes are coupled therefore with decreased perfusion, usually assumed to be secondary to decreased cerebral metabolic demands (Meyer et al., 1999). During ageing declines in cerebral tissue densities in gray (polio-araiosis) and white matter (leuko-araiosis) reflect neuronal degenerative changes, which progress concurrent with cerebral perfusion declines. Rates of polio- and leuko-araiosis accelerate geometrically after age 60, correlating with cortical and subcortical atrophy and ventricular enlargement. In particular, leuko-araiosis correlates with advancing age, cerebral atrophy, hypoperfusion of white matter, and cognitive impairments (Meyer et al., 2000): what is surprising, is that leuko-araiosis is detectable in 9-19% of older \u201cnormal\u201d subjects but is virtually always present in vascular dementia. Of special interest are the data emerging from the study of Meyer et al. (2000): normative subjects destined for later cognitive decline had excessive leuko-araiosis at study entry, suggesting leukoaraiosis is, itself, a risk factor for cognitive decline.We have studied the emerging role of hypotension in SVAD definitio

Correction: Equilibrium gels of low-valence DNA nanostars: a colloidal model for strong glass formers

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Small-angle neutron scattering and Molecular Dynamics structural study of gelling DNA nanostars

DNA oligomers with properly designed sequences self-assemble into well defined constructs. Here, we exploit this methodology to produce bulk quantities of tetravalent DNA nanostars (each one composed by 196 nucleotides) and to explore the structural signatures of their aggregation process. We report small-angle neutron scattering experiments focused on the evaluation of both the form factor and the temperature evolution of the scattered intensity at a nano star concentration where the system forms a tetravalent equilibrium gel. We also perform molecular dynamics simulations of one isolated tetramer to evaluate the form factor theoretically, without resorting to any approximate shape. The numerical form factor is found to be in very good agreement with the experimental one. Simulations predict an essentially temperature independent form factor, offering the possibility to extract the effective structure factor and its evolution during the equilibrium gelation.Comment: 9 pages, 5 figure

Postoperative delirium in kidney transplant patients

Delirium, also known as acute brain failure, is a medical condition characterized by recent onset of confusion, fluctuating awareness, disorganized thought, with memory and attention impairment. Post-operative delirium (POD) generally arises 1 to 3 days after surgery, in 25-37% of the hospitalized patients and in > 65% of those admitted to intensive care unit [1]

Increased age and male sex are independently associated with higher frequency of blood–cerebrospinal fluid barrier dysfunction using the albumin quotient

Background: The cerebrospinal fluid (CSF)/serum quotient of albumin (QAlb) is the most used biomarker for the evaluation of blood–cerebrospinal fluid barrier (B-CSF-B) permeability. For years QAlb was considered only as an age-related parameter but recently it has also been associated to sex. The aim of the present study was to explore the impact of sex in the determination of B-CSF-B dysfunction. Methods: The analysis was retrospectively conducted on subjects consecutively admitted to the neurological ward. CSF and serum albumin levels were measured by immunonephelometry and pathological QAlb thresholds were considered: 6.5 under 40 years, 8.0 in the age 40–60 and 9.0 over 60 years. Results: 1209 subjects were included in the study. 718 females and 491 males (age: 15–88 years): 24.6% of patients had a diagnosis of multiple sclerosis, 23.2% suffered from other inflammatory neurological diseases, 24.6% were affected by non-inflammatory neurological diseases, and for 27.6% of patients the final neurological diagnosis could not be traced. Dysfunctional B-CSF-B was detected more frequently (44 vs. 20.1%, p < 0.0001) and median QAlb value were higher (7.18 vs. 4.87, p < 0.0001) in males than in females in the overall study population and in all disease sub- groups. QAlb and age were positively correlated both in female (p < 0.0001) and male (p < 0.0001) patients, however the slopes of the two regression lines were not significantly different (p = 0.7149), while the difference between the elevations was extremely significant (p < 0.0001) with a gap of 2.2 units between the two sexes. Finally, in a multivari- able linear regression analysis increased age and male sex were independently associated with higher QAlb in the overall study population (both p < 0.001) and after stratification by age and disease group. Conclusions: Accordingly, identification and validation of sex-targeted QAlb thresholds should be considered as a novel tool in an effort to achieve more precision in the medical approach