120 research outputs found
Temporal variations in leaf traits, chemical composition and in vitro true digestibility of four temperate fodder tree species.
Cyborg Activism: Exploring the reconfigurations of democratic subjectivity in Anonymous
This article develops the concept of cyborg activism as novel configuration of democratic subjectivity in the Information Age by exploring the online collectivity Anonymous as a prototype. By fusing elements of human/machine and organic/digital the cyborg disrupts modern logics of binary thinking. Cyborg activism emerges as the reconfiguration of equality/hierarchy, reason/emotion, and nihilism/idealism. Anonymous demonstrates how through the use of contingent and ephemeral digital personae hierarchies in cyborg activism prove more volatile than in face-to-face settings. Emotions appear as an essential part of a politics of passion, which enables pursuing laughter and joy, expressing anger, and experiencing empowerment as part of a reasoned, strategic politics. Anonymous’ political content reconfigures nihilist sentiments, frustration, and political disenchantment on the one hand with idealist world views on the other. This enables the cohabitation and partial integration of a great diversity of political claims rooted in various ideologies
COAUTHOR - a MoU to create a COnsortium of Academics from Universities promoting the use of THORium
This paper describes the Memorandum of Understanding (MoU) signed by the authors to create a future consortium of academics from universities to promote the utilization of thorium (COAUTHOR). Besides the description of the MoU, also results of the research conducted in each participating partner or collaborative work performed among them will be described. Finally, the future work planned in the framework of the MoU, will be discussed
A MoU to create a COnsortium of Academics from Universities promoting the use of THORrium (COAUTHOR)
Nuclear Energy, primarily to produce electricity and other use, and the enveloping Nuclear Technology, as inherited from the XX Century, constitutes a controversial issue for political and economic reasons. On the one hand, the energy source is promoted in several Countries and an unavoidable mean to ensure growth for the human civilization ad suitable living standard with reduced or no impact upon the environment, on the other hand it is abandoned or going to be abandoned in other Countries which did benefit of stable economic growth. Thorium is an emblem for such a situation: huge reserves are available all over the world (primarily India, Turkey, and Brazil, but not only) and its technological worth for exploitation in current generation of thermal fission reactors is demonstrated, on the other hand no industrial use is ongoing or planned for the near future (with an exception constituted by situation in India). Moreover, research on thorium utilization in nuclear reactors and associated fuel cycles has been of academic interest for many researchers around the world. These researches are being conducted to increase the natural resource utilization, reduces the radiotoxicity, and other criteria of sustainability, by using thorium in the present time advanced reactors (Generation III), as well for the future Generation IV, mainly in Molten Salt Reactors (MSR) and in hybrid fusion/ accelerators driven system. Here we are going to describe a MoU signed by the authors to promote the utilization of thorium as nuclear fuel, and shortly describe the research activities conducted by the MoU partners
A time and frequency domain analysis of the effect of vibrating fuel assemblies on the neutron noise
[EN] The mechanical vibrations of fuel assemblies have been shown to give rise to high levels of neutron noise, triggering in some circumstances the necessity to operate nuclear reactors at a reduced power level. This work analyses the effect in the neutron field of the oscillation of one single fuel assembly. Results show two different effects in the neutron field caused by the fuel assembly vibration. First, a global slow variation of the total reactor power due to a change in the criticality of the system. Second, an oscillation in the neutron flux in-phase with the assembly vibration. This second effect has a strong spatial dependence that can be used to localize the oscillating assembly. This paper shows a comparison between a time-domain and a frequency-domain analysis of the phenomena to calculate the spatial response of the neutron noise. Numerical results show a really close agreement between these two approaches.This project has received funding from the Euratom research and training programme 2014-2018 under grant agreement No 754316. Also, this work has been partially supported by Spanish Ministerio de Economia y Competitividad under project BES-2015-072901 and financed with the help of a Primeros Proyectos de Investigation (PAID-06-18), Vicerrectorado de Investigacitin, Innovation y Transferencia of the Universitat Politecnica de Valencia (UPV).Vidal-Ferràndiz, A.; Carreño, A.; Ginestar Peiro, D.; Demazière, C.; Verdú Martín, GJ. (2020). A time and frequency domain analysis of the effect of vibrating fuel assemblies on the neutron noise. Annals of Nuclear Energy. 137:1-12. https://doi.org/10.1016/j.anucene.2019.107076S112137Akcasu, Z. (1958). General Solution of the Reactor Kinetic Equations without Feedback. Nuclear Science and Engineering, 3(4), 456-467. doi:10.13182/nse58-a25482Antonopoulos-Domis, M. (1976). Reactivity and neutron density noise excited by random rod vibration. Annals of Nuclear Energy, 3(9-10), 451-459. doi:10.1016/0306-4549(76)90030-xDemaziere, C. (2006). Analysis methods for the determination of possible unseated fuel assemblies in BWRs. International Journal of Nuclear Energy Science and Technology, 2(3), 167. doi:10.1504/ijnest.2006.010713Demazière, C. (2011). CORE SIM: A multi-purpose neutronic tool for research and education. Annals of Nuclear Energy, 38(12), 2698-2718. doi:10.1016/j.anucene.2011.06.010Demazière, C., & Andhill, G. (2005). Identification and localization of absorbers of variable strength in nuclear reactors. Annals of Nuclear Energy, 32(8), 812-842. doi:10.1016/j.anucene.2004.12.011Demazière, C., Dykin, V., & Jareteg, K. (2017). Development of a point-kinetic verification scheme for nuclear reactor applications. Journal of Computational Physics, 339, 396-411. doi:10.1016/j.jcp.2017.03.020Demazière, C., & Pázsit, I. (2009). Numerical tools applied to power reactor noise analysis. Progress in Nuclear Energy, 51(1), 67-81. doi:10.1016/j.pnucene.2008.01.010Ginestar, D., Verdú, G., Vidal, V., Bru, R., Marín, J., & Muñoz-Cobo, J. L. (1998). High order backward discretization of the neutron diffusion equation. Annals of Nuclear Energy, 25(1-3), 47-64. doi:10.1016/s0306-4549(97)00046-7Hébert, A. (1985). Application of the Hermite Method for Finite Element Reactor Calculations. Nuclear Science and Engineering, 91(1), 34-58. doi:10.13182/nse85-a17127Jonsson, A., Tran, H. N., Dykin, V., & Pázsit, I. (2012). Analytical investigation of the properties of the neutron noise induced by vibrating absorber and fuel rods. Kerntechnik, 77(5), 371-380. doi:10.3139/124.110258Kronbichler, M., & Kormann, K. (2012). A generic interface for parallel cell-based finite element operator application. Computers & Fluids, 63, 135-147. doi:10.1016/j.compfluid.2012.04.012Larsson, V., & Demazière, C. (2009). Comparative study of 2-group and diffusion theories for the calculation of the neutron noise in 1D 2-region systems. Annals of Nuclear Energy, 36(10), 1574-1587. doi:10.1016/j.anucene.2009.07.009Olmo-Juan, N., Demazière, C., Barrachina, T., Miró, R., & Verdú, G. (2019). PARCS vs CORE SIM neutron noise simulations. Progress in Nuclear Energy, 115, 169-180. doi:10.1016/j.pnucene.2019.03.041Park, J., Lee, J. H., Kim, T.-R., Park, J.-B., Lee, S. K., & Koo, I.-S. (2003). Identification of reactor internals’ vibration modes of a Korean standard PWR using structural modeling and neutron noise analysis. Progress in Nuclear Energy, 43(1-4), 177-186. doi:10.1016/s0149-1970(03)00021-0Pázsit, I. (1988). Control-rod models and vibration induced noise. Annals of Nuclear Energy, 15(7), 333-346. doi:10.1016/0306-4549(88)90081-3Pázsit, I., & Th.Analytis, G. (1980). Theoretical investigation of the neutron noise diagnostics of two-dimensional control rod vibrations in a PWR. Annals of Nuclear Energy, 7(3), 171-183. doi:10.1016/0306-4549(80)90082-1Pázsit, I., & Glöckler, O. (1983). On the Neutron Noise Diagnostics of Pressurized Water Reactor Control Rod Vibrations. I. Periodic Vibrations. Nuclear Science and Engineering, 85(2), 167-177. doi:10.13182/nse83-a27424Ravetto, P. (1997). Reactivity oscillations in a point reactor. Annals of Nuclear Energy, 24(4), 303-314. doi:10.1016/s0306-4549(96)00066-7Sunde, C., Demazière, C., & Pázsit, I. (2006). Calculation of the Neutron Noise Induced by Shell-Mode Core-Barrel Vibrations in a 1-D, Two-Group, Two-Region Slab Reactor Model. Nuclear Technology, 154(2), 129-141. doi:10.13182/nt06-1Tran, H.-N., Pázsit, I., & Nylén, H. (2015). Investigation of the ex-core noise induced by fuel assembly vibrations in the Ringhals-3 PWR. Annals of Nuclear Energy, 80, 434-446. doi:10.1016/j.anucene.2015.01.045Vidal-Ferràndiz, A., Carreño, A., Ginestar, D., & Verdú, G. (2019). A Block Arnoldi Method for the SPN Equations. International Journal of Computer Mathematics, 1-22. doi:10.1080/00207160.2019.1602768Vidal-Ferrandiz, A., Fayez, R., Ginestar, D., & Verdú, G. (2014). Solution of the Lambda modes problem of a nuclear power reactor using an h–p finite element method. Annals of Nuclear Energy, 72, 338-349. doi:10.1016/j.anucene.2014.05.026Vidal-Ferràndiz, A., Fayez, R., Ginestar, D., & Verdú, G. (2016). Moving meshes to solve the time-dependent neutron diffusion equation in hexagonal geometry. Journal of Computational and Applied Mathematics, 291, 197-208. doi:10.1016/j.cam.2015.03.040Viebach, M., Bernt, N., Lange, C., Hennig, D., & Hurtado, A. (2018). On the influence of dynamical fuel assembly deflections on the neutron noise level. Progress in Nuclear Energy, 104, 32-46. doi:10.1016/j.pnucene.2017.08.010Weinberg, A. M., & Schweinler, H. C. (1948). Theory of Oscillating Absorber in a Chain Reactor. Physical Review, 74(8), 851-863. doi:10.1103/physrev.74.85
Identification of SERPINA1 as single marker for papillary thyroid carcinoma through microarray meta analysis and quantification of its discriminatory power in independent validation
<p>Abstract</p> <p>Background</p> <p>Several DNA microarray based expression signatures for the different clinically relevant thyroid tumor entities have been described over the past few years. However, reproducibility of these signatures is generally low, mainly due to study biases, small sample sizes and the highly multivariate nature of microarrays. While there are new technologies available for a more accurate high throughput expression analysis, we show that there is still a lot of information to be gained from data deposited in public microarray databases. In this study we were aiming (1) to identify potential markers for papillary thyroid carcinomas through meta analysis of public microarray data and (2) to confirm these markers in an independent dataset using an independent technology.</p> <p>Methods</p> <p>We adopted a meta analysis approach for four publicly available microarray datasets on papillary thyroid carcinoma (PTC) nodules versus nodular goitre (NG) from N2-frozen tissue. The methodology included merging of datasets, bias removal using distance weighted discrimination (DWD), feature selection/inference statistics, classification/crossvalidation and gene set enrichment analysis (GSEA). External Validation was performed on an independent dataset using an independent technology, quantitative RT-PCR (RT-qPCR) in our laboratory.</p> <p>Results</p> <p>From meta analysis we identified one gene (SERPINA1) which identifies papillary thyroid carcinoma against benign nodules with 99% accuracy (n = 99, sensitivity = 0.98, specificity = 1, PPV = 1, NPV = 0.98). In the independent validation data, which included not only PTC and NG, but all major histological thyroid entities plus a few variants, SERPINA1 was again markedly up regulated (36-fold, p = 1:3*10<sup>-10</sup>) in PTC and identification of papillary carcinoma was possible with 93% accuracy (n = 82, sensitivity = 1, specificity = 0.90, PPV = 0.76, NPV = 1). We also show that the extracellular matrix pathway is strongly activated in the meta analysis data, suggesting an important role of tumor-stroma interaction in the carcinogenesis of papillary thyroid carcinoma.</p> <p>Conclusions</p> <p>We show that valuable new information can be gained from meta analysis of existing microarray data deposited in public repositories. While single microarray studies rarely exhibit a sample number which allows robust feature selection, this can be achieved by combining published data using DWD. This approach is not only efficient, but also very cost-effective. Independent validation shows the validity of the results from this meta analysis and confirms SERPINA1 as a potent mRNA marker for PTC in a total (meta analysis plus validation) of 181 samples.</p
Notulae to the Italian native vascular flora: 9
In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions. Two new combinations are proposed. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as Suppl. material
Notulae to the Italian alien vascular flora: 7
In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, and status changes for Italy or for Italian administrative regions of taxa in the genera Abies, Actinidia, Alooe, Amaryllis, Anredera, Arctotheca, Bidens, Cardiospermum, Celosia, Commelina, Cotoneaster, Cyclamen, Eclipta, Euphorbia, Grevillea, Hedera, Hibiscus, Impatiens, Juglans, Kalanchoe, Koelreuteria, Lindernia, Melinis, Myriophyllum, Nandina, Nicotiana, Oenothera, Oxalis, Parthenocissus, Phoenix, Phyllanthus, Physalis, Plumbago, Pteris, Quercus, Setaria, Symphytum, Tagetes, and Washingtonia. Nomenclatural and distribution updates, published elsewhere are provided as Suppl. material 1
Notulae to the Italian native vascular flora: 8
In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions for taxa in the genera Ajuga, Chamaemelum, Clematis, Convolvulus, Cytisus, Deschampsia, Eleocharis, Epi- pactis, Euphorbia, Groenlandia, Hedera, Hieracium, Hydrocharis, Jacobaea, Juncus, Klasea, Lagurus, Leersia, Linum, Nerium, Onopordum, Persicaria, Phlomis, Polypogon, Potamogeton, Securigera, Sedum, Soleirolia, Stachys, Umbilicus, Valerianella, and Vinca. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as Suppl. material
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