164 research outputs found

    Advanced or posponed wage payments: Sraffa validates Marx

    Get PDF
    In his theoretical model of production prices Marx follows the classical economists in treating wages as being paid in advance. Sraffa, instead, tends to treat them as being paid post factum. However, when Marx tackles the problem under less abstract scrutiny, he abandons the classical approach and declares that, as a matter of fact, wages are postponed. We prove that, if the period of postponed wage payment differs from the length of the production process, the correct prices are better approximated by an equation with the full post-payment of wages than by one with full prepayment. Under perfect competition and postponed wage payments, Sraffa’s approach to price determination is the correct one, and validates Marx’s non-classical vision, whatever the period of wage payment

    Sulle tracce dei Vecellio. La famiglia, la bottega, gli affari, i contesti; e la storiografia cadorina

    Get PDF
    La ricerca si \ue8 posta l\u2019obiettivo di indagare la pluralit\ue0 di interessi non direttamente artistici, ma che si incrociano, comunque, con la parallela vicenda pittorica di Tiziano e della famiglia Vecellio. Sono stati raccolti e messi in ordine documenti, in gran parte inediti, illuminanti per le vicende di una famiglia proiettata a garantirsi un ruolo egemone nella patria cadorina grazie al commercio del legname, all\u2019impegno fondiario e all\u2019attivit\ue0 di notariato. Per ricomporre il materiale eterogeneo si \ue8 recuperata la tradizione erudita ottocentesca spesso trascurata e si \ue8 ricorso a materiali di prima mano disseminati in moltissime sedi. Il tutto ripescando reperti gi\ue0 toccati dallo studioso Celso Fabbro - che dedic\uf2 l\u2019intera sua lunga vita a Tiziano - ma rimasti in parte sconosciuti in quanto conservati presso l\u2019archivio della Magnifica Comunit\ue0 Cadorina di Pieve di Cadore. La tesi \ue8 divisa in due sezioni: i profili dei venti eruditi cadorini, la vicenda personale del raccoglitore di memorie Celso Fabbro e le nuove acquisizioni documentarie rinvenute presso la Biblioteca Nazionale Centrale di Roma ma provenienti dal Cadore.The objective of this research was to enquire into the multiplicity of non-directly artistic interests which nevertheless intersected with Titian\u2019s and the Vecellio family\u2019s parallel painting interests. Documents - the bulk of which unexamined - illuminating the affairs of a family whose ambition was a dominant role in its Cadore homeland by means of the timber trade, land estates and notarial work were collected and re-organised. For the purposes of re-organising this heterogeneous material the frequently neglected erudite nineteenth century tradition was recovered and primary sources disseminated over a great many locations were used. This was made possible by the further use of documents previously studied by scholar Celso Fabbro - who dedicated much of his long life to Titian - but which were partially unknown to the extent that they are conserved at the Magnifica Communit\ue0 Cadorina archive in Pieve di Cadore. This thesis is subdivided into two sections: the profiles of twenty erudite Cadore figures, the personal story of Celso Fabbro, memoir collector, and the new document acquisitions sourced at the Biblioteca Nazionale Centrale in Rome but originally from the Cadore

    Chronic treatment with statins increases the availability of selenium in the antioxidant defence systems of hemodialysis patients.

    Get PDF
    Project. Oxidative stress (OS) is enhanced in hemodialysis (HD) patients. Lipid peroxidation and oxidative damage to glycids, proteins and nucleic acids are main consequences of OS and are associated to increased cardiovascular risk. Vitamin E and Glutathione Peroxidase (GSH-Px) represent main antioxidant systems in human cells. Selenium (Se), bound to the active sites of GSH-Px, plays a critical role in this antioxidant defense system. Statins are widely used and extensively investigated in the prevention of cardiovascular disease, notably in high-risk subjects. Several studies suggest that statins show antioxidant effects, protecting low-density lipoproteins from oxidation. Aim of our study was to compare serum Se concentration in ESRD patients on maintenance HD and in homogeneous healthy subjects and to investigate whether chronic assumption of statins may interfere with serum Se concentration in HD patients. Procedure. A total of 103 HD patients and 69 healthy subjects were enrolled; HD patients were then divided into patients who were not treated with statins (group A) and patients who assumed statins since six months at least (group B). Serum Se was determined by atomic absorption spectrometry. Results. Serum Se was significantly lower in HD patients of group A compared to healthy subjects (81.65±19.66mcg/L Vs. 96.47±15.62mcg/L, p<0.0040). However, in HD patients who assumed statins serum Se was significantly higher than in HD patients who did not. (111.83±18.82mcg/L Vs. 81.65±19.66mcg/L, p<0.0001). Conclusions. our results suggest that in HD patients chronic assumption of statins is related to a higher availability of active antioxidant agents and to reduced oxidative stress

    Approaches, Strategies and Theoretical and Practice-Based Research Methods to investigate and archive video art:Some reflections from the REWIND projects

    Get PDF
    This paper will discuss methodologies, approaches and issues, emerging out of three major research projects that have investigated early histories of video art in Europe: REWIND (2004 ongoing), REWINDItalia (2011-2014) and EWVA (2015-2018). The paper will discuss how the projects have engaged with the history of the apparatus, the identity and status of the artworks, preservation methods, and the legacy of these video artworks today. A particular focus will be on semi-structured questionnaires for interviews structured to capture oral histories, memories and recollections, that in some cases would have been otherwise lost to future knowledge and the uncovering of lost artworks and their available documentation. The speakers directly involved in the projects - will discuss solutions, risks and experiences encountered in the projects and future research perspectives for re-covering, collecting, archiving and narrating the histories of early video art in Europe. The paper will discuss also different practice-based research methods, platforms and engagement strategies, including re-installation and re-enactment

    Robust and prototypical immune responses toward COVID-19 vaccine in First Nations peoples are impacted by comorbidities.

    Get PDF
    High-risk groups, including Indigenous people, are at risk of severe COVID-19. Here we found that Australian First Nations peoples elicit effective immune responses to COVID-19 BNT162b2 vaccination, including neutralizing antibodies, receptor-binding domain (RBD) antibodies, SARS-CoV-2 spike-specific B cells, and CD4⁺ and CD8⁺ T cells. In First Nations participants, RBD IgG antibody titers were correlated with body mass index and negatively correlated with age. Reduced RBD antibodies, spike-specific B cells and follicular helper T cells were found in vaccinated participants with chronic conditions (diabetes, renal disease) and were strongly associated with altered glycosylation of IgG and increased interleukin-18 levels in the plasma. These immune perturbations were also found in non-Indigenous people with comorbidities, indicating that they were related to comorbidities rather than ethnicity. However, our study is of a great importance to First Nations peoples who have disproportionate rates of chronic comorbidities and provides evidence of robust immune responses after COVID-19 vaccination in Indigenous people.Wuji Zhang, Lukasz Kedzierski, Brendon Y. Chua, Mark Mayo, Claire Lonzi, Vanessa Rigas, Bianca F. Middleton, Hayley A. McQuilten, Louise C. Rowntree, Lilith F. Allen, Ruth A. Purcell, Hyon-Xhi Tan, Jan Petersen, Priyanka Chaurasia, Francesca Mordant, Mikhail V. Pogorelyy, Anastasia A. Minervina, Jeremy Chase Crawford, Griffith B. Perkins, Eva Zhang, Stephanie Gras, E. Bridie Clemens, Jennifer A. Juno, Jennifer Audsley, David S. Khoury, Natasha E. Holmes, Irani Thevarajan, Kanta Subbarao, Florian Krammer, Allen C. Cheng, Miles P. Davenport, Branka Grubor-Bauk, P. Toby Coates, Britt Christensen, Paul G. Thomas, Adam K. Wheatley, Stephen J. Kent, Jamie Rossjohn, Amy W. Chung, John Boffa, Adrian Miller, Sarah Lynar, Jane Nelson, Thi H. O. Nguyen, Jane Davies, Katherine Kedziersk

    Broad spectrum SARS‐CoV ‐2‐specific immunity in hospitalized First Nations peoples recovering from COVID ‐19

    Get PDF
    Indigenous peoples globally are at increased risk of COVID‐19‐associated morbidity and mortality. However, data that describe immune responses to SARS‐CoV‐2 infection in Indigenous populations are lacking. We evaluated immune responses in Australian First Nations peoples hospitalized with COVID‐19. Our work comprehensively mapped out inflammatory, humoral and adaptive immune responses following SARS‐CoV‐2 infection. Patients were recruited early following the lifting of strict public health measures in the Northern Territory, Australia, between November 2021 and May 2022. Australian First Nations peoples recovering from COVID‐19 showed increased levels of MCP‐1 and IL‐8 cytokines, IgG‐antibodies against Delta‐RBD and memory SARS‐CoV‐2‐specific T cell responses prior to hospital discharge in comparison with hospital admission, with resolution of hyperactivated HLA‐DR+CD38+ T cells. SARS‐CoV‐2 infection elicited coordinated ASC, Tfh and CD8+ T cell responses in concert with CD4+ T cell responses. Delta and Omicron RBD‐IgG, as well as Ancestral N‐IgG antibodies, strongly correlated with Ancestral RBD‐IgG antibodies and Spike‐specific memory B cells. We provide evidence of broad and robust immune responses following SARS‐CoV‐2 infection in Indigenous peoples, resembling those of non‐Indigenous COVID‐19 hospitalized patients

    Behavioural plasticity in Argyrodes antipodiana.

    Get PDF
    In this thesis I look at the behavioural plasticity of A.antipodiana while foraging and interacting with conspecifics. The aim is to see how an animal, with apparently limited intelligence is able to deal with environmental variability. I conclude that A.antipodiana appears to have been able to overcome these limitations very effectively by using four methods, of which the first two effectively reduce the amount of learning necessary. Firstly, A.antipodiana simplifies the situation as much as possible by ignoring some of the variability. For example, in social situations, A.antipodiana appears to recognize only a few categories of conspecifics, rather than recognize conspecifics as individuals. Consequently, the social groups of A.antipodiana are not characterized by complicating factors such as aggressive orders or dominance hierarchies. Secondly, A.antipodiana largely ignores current situations and instead bases much of its behavioural decisions on its internal conditions. For example, in male-male conflicts, males respond to their opponents largely according to their own size, level of hunger, the number of contests in which they have participated, or their past experience of winning or losing; rather than to the characteristics of their opponents. Likewise in social interactions A.antipodiana is more inclined to be aggressive towards conspecifics if it itself is foraging, and less inclined if it is feeding with the host. When the situation cannot be simplified, A.antipodiana adopts a third response which is to use the simplest method possible for adjusting its behaviour. For example, A.antipodiana's ability to develop araneophagic skills appears to be governed by a critical period. Thus rather than developing araneophagic skills through trial and error with practise, the ability appears to be simply 'switched on' if required. The fourth means by which A.antipodiana compensates for limited intelligence is to be very selective in the areas in which it does use learning. For example, A.antipodiana seems to use problem solving when foraging, but only when it is actually trying to reach the food bundle upon which the host is feeding. A.antipodiana also seems to learn to move more stealthfully on the host's web. There is even evidence that A.antipodiana may behave with intent when males are competing for opportunities to copulate. Thus the intelligence of A.antipodiana appears to be severely limited. However, despite these limitations, by reducing the amount of learning necessary, and then channelling what learning it has to very restricted, but very poignant areas of its behaviour, A.antipodiana, is able to respond very effectively to its variable environment
    corecore