196,332 research outputs found
“Italian Economists of the 20th Century”, edited by Ferdinando Meacci, Cheltenham: Edward Elgar, 1998
No full textThis book contains twelve essays on some important Italian economists whose works were mostly published in the 20th century. The essays are written mostlty by non-Italian authors and deal with Vilfredo Pareto (by A. Kirman), Maffeo Pantaleoni (Peter Groenewegen), Enrico Barone (P. C. Dooley), Antonio De Viti de Marco (O. Kayaalp), Marco Fanno (R. Arena), Costantino Bresciani-Turroni (H. D. Kurz), Luigi Einaudi (F. Meacci), Piero Sraffa (B. Schefold), Franco Modigliani (C. Dangel), Paolo Sylos Labini (J. Halevi), Pierangelo Garegnani (G. Mongiovi), and L. Luigi Pasinetti (J. R. Teixeira). A short introduction by Ferdinando Meacci opens the volume and advances a suggestive hypothesis for a comprehensive interpretation of the evolution of Italian economic thought during the last century. This introduction is an attempt to treat the thoughts of the twelve economists as a sample from which to infer a brief outline of Italian economics in the 20th century and of its links with economics in general. This outline is sketched in two glimpses. One looks at the economists one after the other according to the period in which they lived (and is accordingly called ‘vertical’). The other looks at them one next to the other according to the methods they have in common (and is accordingly called ‘horizontal’).Italian economists, history of economics, vertical and horizontal
S1P/S1P Receptor Signaling in Neuromuscolar Disorders
No full textThe bioactive sphingolipid metabolite, sphingosine 1-phosphate (S1P), and the signaling pathways triggered by its binding to specific G protein-coupled receptors play a critical regulatory role in many pathophysiological processes, including skeletal muscle and nervous system degeneration. The signaling transduced by S1P binding appears to be much more complex than previously thought, with important implications for clinical applications and for personalized medicine. In particular, the understanding of S1P/S1P receptor signaling functions in specific compartmentalized locations of the cell is worthy of being better investigated, because in various circumstances it might be crucial for the development or/and the progression of neuromuscular diseases, such as Charcot-Marie-Tooth disease, myasthenia gravis, and Duchenne muscular dystrophy
Skeletal Muscle and COVID-19: The Potential Involvement of Bioactive Sphingolipids
No full textSARS-CoV-2 virus infection is the cause of the coronavirus disease 2019 (COVID-19), which is still spreading over the world. The manifestation of this disease can range from mild to severe and can be limited in time (weeks) or persist for months in about 30–50% of patients. COVID-19 is considered a multiple organ dysfunction syndrome and the musculoskeletal system manifestations are beginning to be considered of absolute importance in both COVID-19 patients and in patients recovering from the SARS-CoV-2 infection. Musculoskeletal manifestations of COVID-19 and other coronavirus infections include loss of muscle mass, muscle weakness, fatigue or myalgia, and muscle injury. The molecular mechanisms by which SARS-CoV-2 can cause damage to skeletal muscle (SkM) cells are not yet well understood. Sphingolipids (SLs) represent an important class of eukaryotic lipids with structural functions as well as bioactive molecules able to modulate crucial processes, including inflammation and viral infection. In the last two decades, several reports have highlighted the role of SLs in modulating SkM cell differentiation, regeneration, aging, response to insulin, and contraction. This review summarizes the consequences of SARS-CoV-2 infection on SkM and the potential involvement of SLs in the tissue responses to virus infection. In particular, we highlight the role of sphingosine 1-phosphate signaling in order to aid the prediction of novel targets for preventing and/or treating acute and long-term musculoskeletal manifestations of virus infection in COVID-19
SARS-CoV-2 infection: A role for S1P/S1P receptor signaling in the nervous system?
No full textThe recent coronavirus disease (COVID-19) is still spreading worldwide. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the virus responsible for COVID-19, binds to its receptor angiotensin-converting enzyme 2 (ACE2), and replicates within the cells of the nasal cavity, then spreads along the airway tracts, causing mild clinical manifestations, and, in a majority of patients, a persisting loss of smell. In some individuals, SARS-CoV-2 reaches and infects several organs, including the lung, leading to severe pulmonary disease. SARS-CoV-2 induces neurological symptoms, likely contributing to morbidity and mortality through unknown mechanisms. Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid with pleiotropic properties and functions in many tissues, including the nervous system. S1P regulates neurogenesis and inflammation and it is implicated in multiple sclerosis (MS). Notably, Fingolimod (FTY720), a modulator of S1P receptors, has been approved for the treatment of MS and is being tested for COVID-19. Here, we discuss the putative role of S1P on viral infection and in the modulation of inflammation and survival in the stem cell niche of the olfactory epithelium. This could help to design therapeutic strategies based on S1P-mediated signaling to limit or overcome the host–virus interaction, virus propagation and the pathogenesis and complications involving the nervous system
The amyloid cascade hypothesis and Alzheimer's disease: A mathematical model
No full textThe paper presents a conceptual mathematical model for Alzheimer's disease (AD). According to the so-called amyloid cascade hypothesis, we assume that the progression of AD is associated with the presence of soluble toxic oligomers of beta-amyloid. Monomers of this protein are produced normally throughout life, but a change in the metabolism may increase their total production and, through aggregation, ultimately results in a large quantity of highly toxic polymers. The evolution from monomeric amyloid produced by the neurons to senile plaques (long and insoluble polymeric amyloid chains) is modelled by a system of ordinary differential equations (ODEs), in the spirit of the Smoluchowski equation. The basic assumptions of the model are that, at the scale of suitably small representative elementary volumes (REVs) of the brain, the production of monomers depends on the average degradation of the neurons and in turn, at a much slower timescale, the degradation is caused by the number of toxic oligomers. To mimic prion-like diffusion of the disease in the brain, we introduce an interaction among adjacent REVs that can be assumed to be isotropic or to follow given preferential patterns. We display the results of numerical simulations which are obtained under some simplifying assumptions. For instance, the amyloid cascade is modelled by just three ordinary differential equations (ODEs), and the simulations refer to abstract 2D domains, simplifications which can be easily avoided at the price of some additional computational costs. Since the model is suitably flexible to incorporate other mechanisms and geometries, we believe that it can be generalised to describe more realistic situations
A degraded adhesion model for creep force calculation based on the CONTACT algorithm
No full textDegraded adhesion is observed extensively during the braking or traction process. An accurate degraded adhesion law, on the other hand, is difficult to acquire since it is characterized by a complicated non-linear behaviour involving various surface phenomena. This work provides a new local degraded adhesion model, its implementation in a wheel-rail contact model, and its application in a multibody railway vehicle model. The present degraded adhesion model takes into account large sliding and adhesion recovery phenomena, which are strictly related to the power dissipated at the contact interface. Implementation of the current local degraded adhesion model enhances Kalker's CONTACT algorithm. The application into multibody dynamics simulation demonstrates the high accuracy of computations. The model is validated by comparing it to experimental findings obtained from on-field tests. Simulated results regarding the tangential pressures, the slip velocity, and the dissipated power under degraded adhesion and partial adherence conditions are reported
Detection of neurotropic viruses circulating in Tuscany: the incisive role of Toscana virus
No full textAdenoviruses (Ad) play an important role in the etiology of acute lower respiratory tract infections (ALRI) in young children in Chile. Our aim was to correlate the clinical severity of the infections with the Ad strains isolated during surveillance over 8 years. From 1988 through 1996, nasopharyngeal aspirates (NPA) were obtained for viral isolation and immunofluorescence assay (IFA) from children under 2 years of age hospitalized for ALRI; Ad isolates were further studied by restriction enzyme analysis of genomic DNA Of 3,097 cases enrolled, the Ad isolation rate was 12.6%. The most common admission diagnoses among Ad-positive cases were pneumonia and wheezing bronchitis (69.8%). Duration of Ad shedding was studied in 74 cases by IFA. Children excreting Ad for 4 or more days had a longer hospital stay than those shedding for 1-3 days (mean: 16.8 and 7.2 days, respectively; P< .01). Viral shedding for more than 3 days was associated with more severe outcomes. Genome typing of 221 out of 390 Ad isolates resulted in 87 subgenus C and 134 subgenus B strains, including 123 Ad genome type 7h (55.6%, P< .01). The IFA from the NPA was more sensitive for the detection of subgenus B (51.5%) than subgenus C infections (24.1%, P < .01). Children shedding Ad 7h had longer hospital stays (P < .01), a higher frequency of rectal temperatures over 39°C (P < .01), and greater need for additional oxygen (P< .02) than subgenus C cases. Four cases requiring mechanical ventilation were associated with Ad 7h infections. The data presented show that, in children hospitalized for ALRI, the genome type 7h was associated with a more severe clinical outcome
On Working and Circulating Capital
No full textThe purpose of this paper is to investigate whether the terms “working” and “circulating” capital are two different terms for the same concept; or whether they should be considered two different terms for two different concepts. This purpose will be carried out in two steps. The first is devoted to an investigation of the use of the term “working” by the German economist Lowe (The Path of Economic Growth) and by some Austrian economists (Menger, Böhm-Bawerk, Hayek). The second is devoted to Keynes (A Treatise on Money). At the end of each step an assessment is made of the use of this term by these economists with an extension to the relationship between Lowe’s and Keynes’s treatment of their notion of working capital and two preceding streams of thought. These relationships run between Lowe and the Austrians, in the first case; and between Keynes and the classics (in Marx's sense), in the second. These assessments will eventually converge towards the conclusion that the terms “circulating” and “working” capital are not two different terms for the same notion; and that these two notions are different because they belong to two different theories and require two different methods. The paper argues that the two theories are the classical theory of reproduction and the modern theory of fluctuations as a special branch of the modern theory of production; while the two methods are the method of vertical integration and the method of horizontal integration. The identification of these theories and methods will be pursued more keenly than the differentiation of the two notions of “working” and “circulating” capital in that the aim of this paper is not to resort to the “bestiary” of our subject as if it were a “taxonomy”, let alone to the “taxonomy” as if it were a “machine” (see Shackle: The Years of High Theory, 1967, p.293).Circulating and working capital, reproduction and production, Lowe, Keynes, Austrians
Wealth
No full textThis paper is focused on the notion of wealth as used by different authors in different periods of time. The paper deals with the contrast between the notion of wealth shared by all major classical economists, particularly by Adam Smith, and the notion previously held by the Mercantilists (by which one nation’s gain is intended as another nation’s loss) or subsequently held by Irving Fisher and other Neoclassical economists(whereby the wealth of an individual is brought to centre stage in lieu of the wealth of society). After distinguishing, in Say’s footsteps, between “richesses naturelles” (the use values given by nature) and “richesses sociales” (the use values produced and reproduced by labour), the paper focuses on the classical notion of wealth as “richesses sociales” (the wealth of nations) and, more particularly, as the flow of final goods available in a period (and made possible by using up the intermediate goods inherited from a previous period) rather than the stock, however formed, of instrumental goods (let alone the value of this stock) owned by individuals at an instant of time (assets).wealth, final goods, instrumental goods, flows, stocks
Fictitious Capital and Crises
No full textThis paper is concerned with chapters 25-35 of Part V, The Division of Profit into Interest and Profit of Enterprise, of Volume 3 of Capital. These chapters may be properly grouped in an ideal Part to be possibly titled "Credit and Crises, or Money Capital and Fictitious Capital" and is referred to in this paper as 'the unidentified Part'. This Part should be strictly considered as a follow-up of Part IV, The Transformation of Commodity Capital and Money Capital into Commodity-Dealing Capital and Money-Dealing Capital (Merchant's Capital) in the sense that while the former deals with the role played by merchant's capital, and particularly by money-dealing capital, the latter deals with the obstruction or perversion inflicted on this role by money capital being turned into fictitious capital by an improper use of credit. The paper is structured in three ideal sections. The aim of the first section is to clear the debris of 'the unidentified Part' and to reconstruct Marx's own thinking about the nature and role of credit and of fictitious capital in relation to the concept of merchant's capital and to the phenomenon of crises. On the contrary, the second section, which is mostly focused on different forms versus different sets of crises, highlights some contradictions in Marx's unsystematic treatment of the relations between financial and real crises. The third section is derived from the arguments set out in the previous two sections. Its aim is to assess Marx's similarity with Keynes on the matter of 'money as money' and of financial crises. Its conclusion (which is also the conclusion of the paper) is that this similarity, however strong with regard to the role of money as a store of value, is bound to collapse if Marx's law of the falling rate of profit is believed to be true. For in this case the fictitious-capital theory of crises developed in 'the unidentified Part' acquires a secondary importance while financial crises come to be viewed as a typical effect, rather than as the cause, of real crises.Marx, fictitious capital, money capital, financial crises
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