1,361 research outputs found

    "The authority of the steam" : power dynamics of digital production in the Bitcoin blockchain

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    This thesis offers a critical investigation of the Bitcoin currency and the operation of its technical structure, i.e. blockchain technology. The main objective of the research is to identify and describe the specific power dynamics performed by and through this digital phenomenon. “Power dynamics” are framed in this work largely in terms of authority and sovereignty. To structure an exploration of such dynamics, the narrative is overarched by four different notions of “utopia” —as paradox, ideal, no-place, and imagined governance— that address the following main questions always underpinned by the general inquiry on power: What is the Bitcoin Blockchain? Where is it located? How are power relations performed in it? And how are power relations modified in relation with previous institutional systems? The thesis addresses distinct notions of authority in Bitcoin through the observation of its historical, spatial, and organizational characteristics. It maps the techno-political emergence of the blockchain system, the geographical distribution of Bitcoin’s infrastructural network, and the strategies for governance involved in its development as software. Based on the observation of these settings, this thesis argues that Bitcoin posits a restructuration of power dynamics through the automation of code, in particular, through its process of production. In order to develop this restructuration, the power dynamics of the Bitcoin blockchain are weighted against authority models of the state’s institutions. The thesis builds upon existing political theories of Empire (Hardt and Negri), protocol (Galloway), and the Stack (Bratton) to develop a critical account of Bitcoin’s power dynamics. The work sits in between the disciplines of Media Theory, Software Studies, Political Theory, and Digital Methods, and makes use of qualitative and quantitative methods to empirically support the former argument

    Superabundant design

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    Tiziana Terranova draws attention to the necessity of questioning how algorithmically enabled automation works “in terms of control and monetization” and “what kind of time and energy” is being subsumed by it (Terranova 387). Cryptocurrencies are payment technologies that automate the production of money-like tokens (Bergstra and Weijland) following algorithmic rules to maintain a fixed production rate. Different kinds of energy and residues, which are not always acknowledged, are involved in this process. Here I distinguish between two closely linked layers in the Bitcoin token production: first, an algorithmic layer, which contains the instructions and rules for the creation of bitcoins; second, a hardware layer, which performs and embodies the former. While these layers work together, I will argue that they enact their own kind of logics of energy and waste. I will begin at the more visible end of the production cycle, the hardware layer, where the definition of waste and energy consumption is shared with many electronic devices; then I will trace back its algorithmic layer, which as I argue, follows a different logic

    Medición de parámetros fisicos, biológicos y químicos en el tramo estuarino del río Ebro

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    En este artículo se describen las campañas de campo CYTMAR I y II realizadas en la primavera y el verano de 1997, con el fin de estudiar los procesos y los flujos físicos, biológicos y químicos en la zona del Delta del Ebro, tanto en el tramo estuarino del río como en la pluma de agua dulce que se forma en las cercanías de la desembocadura. Aquí el estudio se ha centrado en la zona estuarina, presentando algunos resultados preliminares y analizando las diferencias estacionales observadas

    Tracking the antibody immunome in sporadic colorectal cancer by using antigen self-assembled protein arrays

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    © 2021 by the authors.Sporadic Colorectal Cancer (sCRC) is the third leading cause of cancer death in the Western world, and the sCRC patients presenting with synchronic metastasis have the poorest prognosis. Genetic alterations accumulated in sCRC tumor cells translate into mutated proteins and/or abnormal protein expression levels, which contribute to the development of sCRC. Then, the tumor-associated proteins (TAAs) might induce the production of auto-antibodies (aAb) via humoral immune response. Here, Nucleic Acid Programmable Protein Arrays (NAPPArray) are employed to identify aAb in plasma samples from a set of 50 sCRC patients compared to seven healthy donors. Our goal was to establish a systematic workflow based on NAPPArray to define differential aAb profiles between healthy individuals and sCRC patients as well as between non-metastatic (n = 38) and metastatic (n = 12) sCRC, in order to gain insight into the role of the humoral immune system in controlling the development and progression of sCRC. Our results showed aAb profile based on 141 TAA including TAAs associated with biological cellular processes altered in genesis and progress of sCRC (e.g., FSCN1, VTI2 and RPS28) that discriminated healthy donors vs. sCRC patients. In addition, the potential capacity of discrimination (between non-metastatic vs. metastatic sCRC) of 7 TAAs (USP5, ML4, MARCKSL1, CKMT1B, HMOX2, VTI2, TP53) have been analyzed individually in an independent cohort of sCRC patients, where two of them (VTI2 and TP53) were validated (AUC ~75%). In turn, these findings provided novel insights into the immunome of sCRC, in combination with transcriptomics profiles and protein antigenicity characterizations, wich might lead to the identification of novel sCRC biomarkers that might be of clinical utility for early diagnosis of the tumor. These results explore the immunomic analysis as potent source for biomarkers with diagnostic and prognostic value in CRC. Additional prospective studies in larger series of patients are required to confirm the clinical utility of these novel sCRC immunomic biomarkers.We gratefully acknowledge financial support from the Spanish Health Institute Carlos III (ISCIII) for the grants: FIS PI14/01538, FIS PI17/01930 and CB16/12/00400. We also acknowledge Fondos FEDER (EU) “Una manera de hacer Europa” and Junta Castilla-León (COVID19 grant COV20EDU/00187). Fundación Solórzano FS/38-2017. The Proteomics Unit belongs to ProteoRed, PRB3-ISCIII, supported by grant PT17/0019/0023, of the PE I + D + I 2017-2020, funded by ISCIII and FEDER. CNPq-National Council for Scientific and Technological Development (Brazil) (306258/2019-6) and FAPERJ-Foundation for Research Support of Rio de Janeiro State for the financial support (E-26/201.670/2017 and 210.379/2018). M. González-González is supported by MINECOPTA2019-017870-I.A. Landeira-Viñuela is supported by VIII Centenario-USAL PhD Program. P.J.-V. is supported by JCYL PhD Program and scholarship JCYL-EDU/601/2020. P.D. and E.B. are supported by a JCYL-EDU/346/2013 Ph.D. scholarship

    Medición de parámetros fisicos, biológicos y químicos en el tramo estuarino del río Ebro

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    [ES] En este artículo se describen las campañas de campo CYTMAR I y II realizadas en la primavera y el verano de 1997, con el fin de estudiar los procesos y los flujos físicos, biológicos y químicos en la zona del Delta del Ebro, tanto en el tramo estuarino del río como en la pluma de agua dulce que se forma en las cercanías de la desembocadura. Aquí el estudio se ha centrado en la zona estuarina, presentando algunos resultados preliminares y analizando las diferencias estacionales observadas.Este trabajo forma parte del proyecto FANS (contrato No. MAS3-CT95-0037) del Programa MAST-III de la Unión Europea y del proyecto MAR96-1856 del Programa CYTMAR de la Comisión Interministerial de Ciencia y Tecnología (CICYT). También se agradece la contribución de todos los que participaron en las campañas de campo. Finalmente cabe destacar la colaboración de la Confederación Hidrográfica del Ebro, que proporcionó los datos de caudales del río y del Centro de Estudios de Puertos y Costas (CEPYC) del CEDEX, que prestó algunos de los equipos utilizados en las campañas.Sierra Pedrico, JP.; González Del Río Rams, J.; Flos Bassols, J.; Sánchez-Arcilla Conejo, A.; Movellán Mendoza, E.; Rodilla, M.; Mösso Aranda, C.... (2001). Medición de parámetros fisicos, biológicos y químicos en el tramo estuarino del río Ebro. Ingeniería del Agua. 8(4):459-468. https://doi.org/10.4995/ia.2001.2879SWORD45946884Bruno, M., Fraguela, B., Alonso, J.J., Ruiz Cañavate, A., Mañanes, R. and Rico, J. (1997). Atmospheric pressure variations and water mass exchange between the continental shelf and the Bay of Cadiz. Scientia Marina, 61, pp. 379-387.Day, J.W., J.F. Martin, L. Cardoch and P.H. Templet (1997). System functioning as a basis for sustainable management of deltaic ecosystems. Costal Management, 25, pp. 115-153.Geyer, W.R. and Farmer, D.M. (1989). Tide induced variation in the dynamics of a salt wedge estuary. J. Physical Oceanography, 19, pp. 1060-1072.Huisman, J. and Weissing, F.J. (1995). Competition for nutrients and light among phytoplankton species in a mixed water column: theoretical studies. Water Sci. Tech., 32, pp. 143-147.Ibáñez, C. (1993). Dinámica hidrológica y funcionamiento ecológico del tramo estuarino del río Ebro. Tesis doctoral, Universidad de Barcelona, 196 p.Ibáñez, C., Pont, D. and Prat, N. (1997). Characterization of the Ebre and Rhone estuaries: A basis for defining and classifying salt-wedge estuaries. Limnol. Oceanogr., 42, pp. 89-101.Morris, A.W., Bale, A.J. and Howland, R.J.M. (1981). Nutrient distributions in an estuary: evidence of chemical precipitation of dissolved silicate and phosphate. Estuarine, Coastal and Shelf Science, 12, pp. 205-216.Smith, N.P. (1986). Subtidal Exchanges between Corpus Christi Bay and Texas Inner Shelf Waters. Lecture Notes on Coastal and Estuarine Studies. Ed. Van Kreeke, Springer Verlag, 16, pp. 143-152.Valle-Levinson, A. (1995). Observations of barotropic and baroclinic exchanges in the lower Chesapeake Bay. Continental Shelf Research, 15, pp. 1631-1647.Velasco, M.J. (1998). Descripción de los procesos hidro-biogeoquímicos en el Delta del Ebro. Tesina de graduación. Universitat Politècnica de Catalunya, 133p.Zessner, M. et al. (1996). Regional materials accounting of nitrogen in upper Austria. Water Sci. Tech., 33, pp. 89-97

    Persistent Pulmonary Hypertension in Corrected Valvular Heart Disease: Hemodynamic Insights and Long-Term Survival.

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    Background The determinants and consequences of pulmonary hypertension after successfully corrected valvular heart disease remain poorly understood. We aim to clarify the hemodynamic bases and risk factors for mortality in patients with this condition. Methods and Results We analyzed long-term follow-up data of 222 patients with pulmonary hypertension and valvular heart disease successfully corrected at least 1 year before enrollment who had undergone comprehensive hemodynamic and imaging characterization as per the SIOVAC (Sildenafil for Improving Outcomes After Valvular Correction) clinical trial. Median (interquartile range) mean pulmonary pressure was 37 mm Hg (32-44 mm Hg) and pulmonary artery wedge pressure was 23 mm Hg (18-26 mm Hg). Most patients were classified either as having combined precapillary and postcapillary or isolated postcapillary pulmonary hypertension. After a median follow-up of 4.5 years, 91 deaths accounted for 4.21 higher-than-expected mortality in the age-matched population. Risk factors for mortality were male sex, older age, diabetes mellitus, World Health Organization functional class III and higher pulmonary vascular resistance-either measured by catheterization or approximated from ultrasound data. Higher pulmonary vascular resistance was related to diabetes mellitus and smaller residual aortic and mitral valve areas. In turn, the latter correlated with prosthetic nominal size. Six-month changes in the composite clinical score and in the 6-minute walk test distance were related to survival. Conclusions Persistent valvular heart disease-pulmonary hypertension is an ominous disease that is almost universally associated with elevated pulmonary artery wedge pressure. Pulmonary vascular resistance is a major determinant of mortality in this condition and is related to diabetes mellitus and the residual effective area of the corrected valve. These findings have important implications for individualizing valve correction procedures. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00862043.This study was funded by the Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación, Spain, the European Union–European Regional Development Fund (EC07/90772 and PI19/00649), and the Consorcio de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV).S

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    The SuperCam Instrument Suite on the Mars 2020 Rover: Science Objectives and Mast-Unit Description

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    On the NASA 2020 rover mission to Jezero crater, the remote determination of the texture, mineralogy and chemistry of rocks is essential to quickly and thoroughly characterize an area and to optimize the selection of samples for return to Earth. As part of the Perseverance payload, SuperCam is a suite of five techniques that provide critical and complementary observations via Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman and Luminescence (TRR/L), visible and near-infrared spectroscopy (VISIR), high-resolution color imaging (RMI), and acoustic recording (MIC). SuperCam operates at remote distances, primarily 2-7 m, while providing data at sub-mm to mm scales. We report on SuperCam's science objectives in the context of the Mars 2020 mission goals and ways the different techniques can address these questions. The instrument is made up of three separate subsystems: the Mast Unit is designed and built in France; the Body Unit is provided by the United States; the calibration target holder is contributed by Spain, and the targets themselves by the entire science team. This publication focuses on the design, development, and tests of the Mast Unit; companion papers describe the other units. The goal of this work is to provide an understanding of the technical choices made, the constraints that were imposed, and ultimately the validated performance of the flight model as it leaves Earth, and it will serve as the foundation for Mars operations and future processing of the data.In France was provided by the Centre National d'Etudes Spatiales (CNES). Human resources were provided in part by the Centre National de la Recherche Scientifique (CNRS) and universities. Funding was provided in the US by NASA's Mars Exploration Program. Some funding of data analyses at Los Alamos National Laboratory (LANL) was provided by laboratory-directed research and development funds

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    Relationship between self-reported dietary intake and physical activity levels among adolescents: The HELENA study

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    Background Evidence suggests possible synergetic effects of multiple lifestyle behaviors on health risks like obesity and other health outcomes. Therefore it is important to investigate associations between dietary and physical activity behavior, the two most important lifestyle behaviors influencing our energy balance and body composition. The objective of the present study is to describe the relationship between energy, nutrient and food intake and the physical activity level among a large group of European adolescents. Methods The study comprised a total of 2176 adolescents (46.2% male) from ten European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. Dietary intake and physical activity were assessed using validated 24-h dietary recalls and self-reported questionnaires respectively. Analyses of covariance (ANCOVA) were used to compare the energy and nutrient intake and the food consumption between groups of adolescents with different physical activity levels (1st to 3rd tertile). Results In both sexes no differences were found in energy intake between the levels of physical activity. The most active males showed a higher intake of polysaccharides, protein, water and vitamin C and a lower intake of saccharides compared to less active males. Females with the highest physical activity level consumed more polysaccharides compared to their least active peers. Male and female adolescents with the highest physical activity levels, consumed more fruit and milk products and less cheese compared to the least active adolescents. The most active males showed higher intakes of vegetables and meat, fish, eggs, meat substitutes and vegetarian products compared to the least active ones. The least active males reported the highest consumption of grain products and potatoes. Within the female group, significantly lower intakes of bread and cereal products and spreads were found for those reporting to spend most time in moderate to vigorous physical activity. The consumption of foods from the remaining food groups, did not differ between the physical activity levels in both sexes. Conclusion It can be concluded that dietary habits diverge between adolescents with different self-reported physical activity levels. For some food groups a difference in intake could be found, which were reflected in differences in some nutrient intakes. It can also be concluded that physically active adolescents are not always inclined to eat healthier diets than their less active peers.The HELENA study took place with the financial support of the European Community Sixth RTD Framework Programme (Contract FOOD-CT: 2005-007034). This work was also partially supported by the European Union, in the framework of the Public Health Programme (ALPHA project, Ref: 2006120), the Swedish Council for Working Life and Social Research (FAS), the Spanish Ministry of Education (EX-2007-1124, and EX-2008-0641), and the Spanish Ministry of Health, Maternal, Child Health and Development Network (number RD08/0072) (JPRL, LAM)
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