1,721,054 research outputs found
The graphical representation of the inequality
No full textStarting from the last century, the analysis and the graphical representation of the inequality play a very important role in economics. In the literature several curves have been proposed and developed to simplify the description of the inequality. The aim of this paper is a review and a comparision of the most know inequality curves,evaluating the features of each, with a particular focus on the interpretatio
A comparison of income distributions models through inequality curves
No full textIn this paper the features of some distribution models used in the literature to depict income distributions are analysed. The analysis is based on the inequality curves generated by such models. In particular, the role of the parameters related to the inequality curves is investigated, also by considering the influence of their variations from a pointwise perspective
A comparison of income distributions models through inequality curves
No full textIn this paper the features of some distribution models used in the literature to depict income distributions
are analysed. The analysis is based on the inequality curves generated by such models. In
particular, the role of the parameters related to the inequality curves is investigated, also by considering
the influence of their variations from a pointwise perspective
Cancer and thromboembolism: from biology to clinics
No full textThe association between cancer and thromboembolic disease is a well-known phenomenon and can contribute significantly to the morbidity and mortality of cancer patients. Recent studies evidenced that malignant growth has also been linked to activity of heparin-like glycosoaminoglycans, to neoangiogenesis, to protease activity, to immune function and gene expression in addition with activation of coagulation and fibrinolysis. These evidences suggest that antithrombotic drugs may play an additional role in tumour cell growth and in cancer dissemination. The spectrum of thromboembolic manifestations in cancer patients includes deep vein thrombosis, pulmonary embolism, but also intravascular disseminated coagulation and abnormalities in the clotting system in the absence of clinical manifestations. Antithrombotic drugs such as unfractioned heparin (UFH) and, particularly, low molecular weight heparins (LMWH) in addition with dicumaroids, are widely used for the prevention and treatment of thromboembolic manifestations that commonly accompanies malignancies. The aims of the study are to review the pathogenetic mechanisms of thromboembolic disease in cancer patients, the efficiency of antithrombotic drugs in preventing and treating of cancer related thromboembolic complications and review the thromboprophylaxis strategies to prevent thromboembolic complications of cancer patients. Meta-analyses comparing UFH and LMWH for the treatment of deep vein thrombosis have shown better outcome with reduction of major bleeding complications in patients treated with LMWH. Many studies have demonstrated the efficiency and the safeness of antithrombotic agents in the prophylaxis and in the treatment of thromboembolic complication that accompanies malignancies. Many experimental studies, reviewed in this paper, support the hypothesis that antithrombotic agents, but especially heparins can affect cancer progression in many of the different steps of cancer biology. First of all, due to their anticoagulant effect, antithrombotic agents may interfere with thrombin generation and with fibrin formation induced by cancer cells, thus inhibiting the mechanism of metastasis
On the income distribution models and inequality curves
No full textIn this work the characteristics of some distribution models used in the literature for describing income distribution are analysed. The analysis focuses on the inequality curves generated by such models. In particular, the role of the parameters related to the inequality curves is analysed, also by considering the influence of their variations from a pointwise perspectiv
The Graphical Representation of Inequality - La representación gráfica de la desigualdad
Full text linkAs of the past century, the analysis and the graphical representation of inequality play a very important role in economics. In the literature, several curves have been proposed and developed to simplify the description of inequality. The aim of this paper is a review and a comparison of the most known inequality curves, evaluating the features of each, with a particular focus on interpretation
Regression Models with Compositional Regressors in Case of Structural Zeros
No full textIn many real-life situations, it may happen to consider a regression model with compositional explanatory variables. Compositional data describe parts of some whole, having the feature to sum to a fixed value, so they are commonly presented as vectors of proportions, percentages, or frequencies. In the compositional framework, the presence of structural zeros is problematic, since a composition is not allowed to have a part equal to zero. In the recent years, a few techniques have been introduced in the literature to address the issue. In this paper, three methods (the replacement, the conditioning, and projection approach) are described and illustrated by an example of application
The heparins and cancer: review of clinical trials and biological properties
No full textThe association between cancer and thromboembolic disease is a well-known phenomenon and can contribute significantly to the morbidity and mortality of cancer patients. The spectrum of thromboembolic manifestations in cancer patients includes deep vein thrombosis, pulmonary embolism, but also intravascular disseminated coagulation and abnormalities in the clotting system in the absence of clinical manifestations. Unfractionated heparin (UFH) and particularly low molecular weight heparins (LMWH-s) are widely used for the prevention and treatment of thromboembolic manifestations that commonly accompany malignancies. Malignant growth has also been linked to the activity of heparin-like glycosaminoglycans, to neoangiogenesis, to protease activity, to immune function and gene expression. All these factors contribute in the proliferation and dissemination of malignancies. Heparins may play a role in tumour cell growth and in cancer dissemination. The aims of the study are to review the efficiency of heparins in the prevention and treatment of cancer-related thromboembolic complications, and review the biological effects of heparins. Heparins are effective in reducing the frequency of thromboembolic complications in cancer patients. Meta-analyses comparing unfractionated heparins and LMWH-s for the treatment of deep vein thrombosis have shown better outcome with a reduction of major bleeding complications in patients treated with LMWH-s. LMWH have antitumour effects in animal models of malignancy: heparin oligosaccharides containing less than 10 saccharide residues have been found to inhibit the biological activity of basic fibroblast growth factor (bFGF), whereas heparin fragments with less than 18 saccharide residues have been reported to inhibit the binding of vascular endothelial growth factor (VEGF) to its receptors on endothelial cells. It has been shown that LMWH, in contrast with UFH, can hinder the binding of growth factors to their high-affinity receptors as a result of its smaller size. In vitro heparin fragments of less than 18 saccharide residues reduce the activity of VEGF, and fragments of less than 10 saccharide residues inhibit the activity of bFGF. Small molecular heparin fractions have also been shown to inhibit VEGF- and bFGF-mediated angiogenesis in vivo, in contrast with UFH. Moreover, heparin may influence malignant cell growth through other different interrelated mechanisms: inhibition of (1) heparin-binding growth factors that drive malignant cell growth; (2) tumour cell heparinases that mediate tumour cell invasion and metastasis; (3) cell surface selectin-mediated tumour cell metastasis and blood coagulation. The above evidence, together with favourable pharmaco-properties and with a reduction in major bleeding complications, suggests an important role for LMWH-s in thromboprophylaxis and in the therapy of venous thromboembolism in cancer patients. There is sufficient experimental data to suggest that heparins may interfere with various aspects of cancer proliferation, angiogenesis, and metastasis formation. Large-scale clinical trials are required to determine the clinical impact of the above activities on the natural history of the diseas
Method of moments for Zenga's distribution
No full textThe aim of this paper is to obtain the analytical solution to the
method of moments for Zenga's model (Zenga, M. M., 2010). First,
the central moments of Polisicchio's distribution are used to derive
the corresponding central moments for Zenga's model. Secondly, the
method of moments is applied to such central moments, and then the
analytical solution of the related system is obtained. These analytical
results are then compared with the numerical ones in Zenga et al.
(2010a)
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