Search results for "model."
showing 10 items of 23664 documents
Comparison of different theory models and basis sets in the calculation of 13C NMR chemical shifts of natural products.
2004
The influence of the calculation method in mimicking experimental 13C NMR chemical shifts of 15 low-polarity natural products singularly containing 10–20 carbon atoms was investigated by employing different quantum chemistry approaches and basis sets, both in the preliminary geometry optimizations and in the following single-point 13C GIAO calculations of the NMR chemical shifts. The geometries of the involved species were optimized at the PM3, HF, B3LYP and mPW1PW91 levels whereas the 13C NMR parameters were determined at the HF, B3LYP and mPW1PW91 levels. Different combinations of basis sets were also tested. The consistency and efficiency of the considered combinations of geometry optimi…
Study of Intumescent Coatings Growth for Fire Retardant Systems in Naval Applications: Experimental Test and Mathematical Model
2022
Onboard ships, fire is one of the most dangerous events that can occur. For both military and commercial ships, fire risks are the most worrying; for this reason they have an important impact on the design of the vessel. The intumescent coatings react when heated or in contact with a living flame, and a multi-layered insulating structure grows up, protecting the underlying structure. In this concern, the aim of the paper is to evaluate the intumescent capacity of different composite coatings coupling synergistically modeling and experimental tests. In particular, the experiments have been carried out on a new paint formulation, developed by Colorificio Atria S.r.l., in which the active comp…
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…
Transmisión de señales mecánicas en células indiferenciadas neuroblásticas. Estudios biológicos y preclínicos en modelos in vitro 3D
2023
La biotensegridad es un principio físico de autoequilibrio en el que las fuerzas de tensión y compresión sostienen las estructuras biológicas y permiten la mecanotransducción de señales durante las interacciones célula-célula y célula-entorno. De esta manera, las células y los tejidos responden a las condiciones de su entorno y se adaptan a él. En este sentido, el cáncer muestra sus propios sistemas biotensegrales aberrantes que impulsan la carcinogénesis y la evolución de la enfermedad. La biotensegridad tumoral se define por la intercomunicación entre las poblaciones de células tumorales, los elementos de la matriz extracelular y las estructuras y moléculas del microambiente tumoral. En l…
Identifying the Neurocognitive bases of creativity to increase human and computational creativity
2022
En esta Tesis Doctoral se ha identificado la estructura neurocognitiva que sustenta la creatividad humana a partir del análisis conjunto de más de 800 referencias bibliográficas que muestran las investigaciones más importantes realizadas hasta la fecha. Sobre la base de esta estructura, se ha identificado un paradigma neurocognitivo de la creatividad humana y se ha propuesto un modelo neurocognitivo del proceso creativo. Finalmente, también se ha propuesto un paradigma creativo neurocognitivo computacional y se ha diseñado la estructura de un sistema computacional creativo, basado en una estructura multiagente. La investigación que se ha realizado sobre el tema hasta la fecha es muy especia…
General approaches of processes involved in neurodegeneration using protein and printed phospholipids models
2023
The lizard cerebral cortex as a model to study neuronal regeneration
2002
The medial cerebral cortex of lizards, an area homologous to the hippocampal fascia dentata, shows delayed postnatal neurogenesis, i.e., cells in the medial cortex ependyma proliferate and give rise to immature neurons, which migrate to the cell layer. There, recruited neurons differentiate and give rise to zinc containing axons directed to the rest of cortical areas, thus resulting in a continuous growth of the medial cortex and its zinc-enriched axonal projection. This happens along the lizard life span, even in adult lizards, thus allowing one of their most important characteristics: neuronal regeneration. Experiments in our laboratory have shown that chemical lesion of the medial cortex…