Search results for "Modeling"

Management of Osteoporosis in Postmenopausal Women

2019

Osteoporosis is a noncommunicable disease with increasing incidence at a global level. The burden of the disease particularly concerns women. A drastic and rapid decline in the circulating levels of estrogens, a key regulator of bone metabolism, is responsible for the increase in bone loss after menopause. Cells with a role in bone metabolism, osteoblasts, osteoclasts and osteocytes, have estrogen receptors. The fall in estrogens increases the differentiation of osteoclasts from progenitors in the bone marrow. A significant expansion in the resorption process follows.

Checklist of the Mammal Collection Preserved at the University of Palermo under the Framework of the National Biodiversity Future Center

2023

The latest reorganization of the Vertebrate collections preserved at the “Pietro Doderlein” Museum of Zoology of the University of Palermo (Italy) has made it possible to draw up a check-list of the Mammal taxa present in the stuffed (M), fluid-preserved (ML) and anatomical (AN) collections. The intervention was planned under the National Biodiversity Future Center (NBFC) agenda, focused on the enhancement of Italian natural history museums. The growing interest in museum collections strongly demands databases available to the academic and policy world. In this paper, we record 679 specimens belonging to 157 specific taxa arranged in 58 families and 16 orders. Most of the species (75.1%) co…

Effects of musicianship and experimental task on perceptual segmentation

2015

The perceptual structure of music is a fundamental issue in music psychology that can be systematically addressed via computational models. This study estimated the contribution of spectral, rhythmic and tonal descriptors for prediction of perceptual segmentation across stimuli. In a real-time task, 18 musicians and 18 non-musicians indicated perceived instants of significant change for six ongoing musical stimuli. In a second task, 18 musicians parsed the same stimuli using audio editing software to provide non-real-time segmentation annotations. We built computational models based on a non-linear fuzzy integration of basic and interaction descriptors of local musical novelty. We found tha…

STUDIO DELLE PROPRIETÀ MECCANICHE ED ELETTROMECCANICHE DI NANOCOMPOSITI E NANOFIBRE MEDIANTE APPROCCI NUMERICI

A New Simple Function for Combustion and Cyclic Variation Modeling in Supercharged Spark Ignition Engines

2022

Research in the field of Internal Combustion (IC) engines focuses on the drastic reduction of both pollutant and greenhouse gas emissions. A promising alternative to gasoline and diesel fuel is represented by the use of gaseous fuels, above all green hydrogen but also Natural Gas (NG). In previous works, the authors investigated the performance, efficiency, and emissions of a supercharged Spark Ignition (SI) engine fueled with mixtures of gasoline and natural gas; a detailed research involving the combustion process of this kind of fuel mixture has been previously performed and a lot of experimental data have been collected. Combustion modeling is a fundamental tool in the design and optimi…

A basic need theory approach to problematic Internet use and the mediating effect of psychological distress

2015

The Internet provides an easily accessible way to meet certain needs. Over-reliance on it leads to problematic use, which studies show can be predicted by psychological distress. Self-determination theory proposes that we all have the basic need for autonomy, competency, and relatedness. This has been shown to explain the motivations behind problematic Internet use. This study hypothesizes that individuals who are psychologically disturbed because their basic needs are not being met are more vulnerable to becoming reliant on the Internet when they seek such needs satisfaction from online activities, and tests a model in which basic needs predict problematic Internet use, fully mediated by p…

Perception of the Fair Social Distribution of Benefits and Costs of a Sports Event: An Analysis of the Mediating Effect between Perceived Impacts and…

2020

Residents&rsquo

A "laboratory" open air in the urban landscape of Palermo

2012

The study intends to make new contributions to knowledge of a interesting "laboratory" in the open air in the urban landscape of Palermo, a cultural and scientific heritage in which architecture, art and decoration coexist in an experiment of collective synergies. The Botanical Garden C enter, with its ten acres of land appears, still, a fervent creative process between artifice and nature, the expression of a specific historical and cultural climate in which expectations converged of a intellectual, scientific and institutional fervor. The academic institution, founded in 1789 with the intention of cultivating useful plants to the arts, crafts and medicine, contributed to the spread of tro…

Noble Gases as Magnetic Probes in Fullerene Chemistry

2016

Since the early 1990s of the previous century, the use of magnetic active noble gas atom to indirectly probe the size and symmetry of fullerene cage has been reviewed. Molecular modeling of nuclear shielding (and chemical shift) using gauge-including atomic orbital (GIAO) approach at several levels of theory, including Hartree–Fock (HF), density functional theory (DFT), and coupled cluster (CC), is discussed. The advantage of using GIAO calculation to predict and closely reproduce experimental 3He and 129Xe NMR spectra is shown.

CALIBRATION OF LÉVY PROCESSES USING OPTIMAL CONTROL OF KOLMOGOROV EQUATIONS WITH PERIODIC BOUNDARY CONDITIONS

2018

We present an optimal control approach to the problem of model calibration for L\'evy processes based on a non parametric estimation procedure. The calibration problem is of considerable interest in mathematical finance and beyond. Calibration of L\'evy processes is particularly challenging as the jump distribution is given by an arbitrary L\'evy measure, which form a infinite dimensional space. In this work, we follow an approach which is related to the maximum likelihood theory of sieves. The sampling of the L\'evy process is modelled as independent observations of the stochastic process at some terminal time $T$. We use a generic spline discretization of the L\'evy jump measure and selec…