Search results for "Modeling"

Computational Modeling of Ascending Thoracic Aortic Aneurysm and Dissection

3D digital tools for the archaeological massive artifacts documentation

2022

This study focuses on 3D acquisition and documentation procedures, innovating and implementing traditional survey methods to promote and increase the efficacy of the historical and archaeological heritage fruition. Especially within museum itineraries, modern digital technologies, if consistently applied, can promote a better interpretative reading, implementing the knowledge of scholars. Moreover, in coherence with the Horizon Europe “Cultural Heritage” area of intervention, for a new future inextricably linked to the history of Cultural Heritage, it is essential to experiment approaches that favor innovative mechanisms of fruition and promotion of works of art, based on the idea that the …

FILTERING CHAOS: A TECHNIQUE TO ESTIMATE DYNAMICAL AND OBSERVATIONAL NOISE IN NONLINEAR SYSTEMS

2005

Nonlinear dynamical models are frequently used to approximate and predict observed physical, biological and economic systems. Such models will be subject to errors both in the model dynamics, and the observations of the underlying system. In order to improve models, it is necessary to understand the causes of error growth. A complication with chaotic models is that small errors may be amplified by the model dynamics. This paper proposes a technique for estimating levels of both dynamical and observational noise, based on the model drift. The method is demonstrated for a number of models, for cases with both stochastic and nonstochastic dynamical errors. The effect of smoothing or treating …

Towards a multi-agent model to prevent damage caused by cocoa mirids to cocoa pods

2019

Agriculture in general and cocoa farm in particular is one of the primary sources of income for several African countries. Although quite useful for the development of Africa, cocoa production is faced with several challenges like the diseases of cocoa trees. Mirid (Sahlbergella singularis) is the worst pest affecting cocoa production across west Africa causing 30% to 40% of damage on cocoa production. It is difficult to control the mirids’ population and its impact on the cacao production. Related works on mirids studied the mirids population as a macroscopic entity without considering local interactions of individual mirids. These models did not consider the behaviours and the environment…

A biphasic calcium phosphate coating for potential drug delivery affects early osseointegration of titanium implants.

2016

Background Calcium phosphate (CaP) surface coatings may accelerate osseointegration and serve as a drug delivery system for mineral-binding biomolecules. In a pilot study, the impact of a commercially available, thin CaP coating on early osseous bone remodeling was compared with a modern, subtractive-treated rough surface (SLA-like) in an animal trial. Methods In 16 rabbits, 32 endosseous implants (CaP; n = 16, SLA-like; n = 16) were bilaterally inserted in the proximal tibia after randomization. After 2 and 4 weeks, bone-implant contact (BIC;%) in the cortical (cBIC) and the trabecular bone (sBIC) as well as volume of bone within the screw thread with the highest amount of new-formed bone …

Phosphorus recovery by struvite crystallization in WWTPs: Influence of the sludge treatment line operation

2010

Phosphorus recovery by struvite (MgNH(4)PO(4).6H(2)O) crystallization is one of the most widely recommended technologies for treating sludge digester liquors especially in wastewater treatments plants (WWTP) with enhanced biological phosphorus removal (EBPR). In this paper, phosphorus recovery by struvite crystallization is assessed using the rejected liquors resulting from four different operational strategies of the sludge treatment line. Phosphorus precipitation and recovery efficiencies of between 80-90% and 70-85%, respectively, were achieved in the four experiments. The precipitates formed were mainly struvite, followed by amorphous calcium phosphate and, in some experiments, by calci…

In vitro evaluation of biomimetic chitosan-calcium phosphate scaffolds with potential application in bone tissue engineering.

2013

This work reports on the physicochemical properties and in vitro cytotoxicity assessment of chitosan–calcium phosphate (Cs–CP) scaffolds for bone tissue engineering, which were synthesized by a novel biomimetic co-precipitation method. X-ray diffraction (XRD) along with scanning electron microscopy (SEM) analysis confirmed the porous morphology of the scaffolds and the amorphous nature of the inorganic phase with different crystallite sizes and the formation of various forms of calcium phosphate. Compressive mechanical testing revealed that the Young’s modulus of the biomaterials is in the range of human trabecular bone. In vitro tests were performed on the biomaterials for up to 14 days to…

Calcium Metabolism in the Elderly

1998

Mineral homeostasis represents one of the multiple areas at risk in the elder population. This includes the ion calcium, which is the most abundant inorganic element in the human body and an essential key for many physiologic processes (1).

The Role of Vitamin K in Bone Remodeling and Osteoporosis

2012

Vitamin K is an essential fat soluble vitamin involved in the regulation of normal coagulation. However, growing evidence highlights that this molecule appears to be also implicated in the regulation of other important biological functions such as bone mineralization, calcium homeostasis, apoptosis, cell growth and signal transduction. In particular, many studies have focused their attention on the protective effects of vitamin K on bone tissue in the outlook of its use in the prevention and treatment of osteoporosis in post-menopausal women. The objective of the present paper is to review data of the literature regarding the metabolic effects of Vitamin K in bone tissue and its clinical ro…

PO-146 Multiple myeloma-derived exosomes carry amphiregulin and are responsible for the uncoupled bone remodelling

2018

Introduction Multiple myeloma (MM) is a hematologic malignancy associated with osteolytic bone disease caused by the perturbation of the functional balance between bone resorption and bone formation. Exosomes, nanosize lipoproteic structures, have been recently recognised as a new mechanism of cell to cell communication during tumour growth and progression. We have previously shown that MM-exosomes are involved in osteolytic lesions but the underlying mechanism is still understood. We hypothesise that the epidermal growth factor receptor ligand Amphiregulin (AREG) can be delivered by multiple myeloma-derived exosomes and participate in modulating the response of the bone microenvironment to…