75 research outputs found

    Implementation of a moving finite element mesh within the catenary-pantograph dynamic interaction

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    En este artículo se presenta la aplicación tecnológica a la interacción dinámica catenaria-pantógrafo de una metodología propuesta para estructuras flexibles sometidas a cargas móviles. En primer lugar se describe el modelado de una malla móvil de elementos finitos que se desplaza sobre el hilo de contacto de forma solidaria al pantógrafo que recorre la catenaria y, posteriormente, se presenta la comparación de esta metodología frente a un modelo de elementos finitos convencional de malla fija. El caso simulado corresponde al propuesto por la norma EN-50318, obteniendo resultados acordes a los intervalos de validación propuestos por dicha norma. La principal ventaja del método de malla móvil reside en que para precisiones análogas el tiempo de cálculo es del orden de 4 veces menor que el modelo clásico.This paper presents a technological application of a general methodology to analyze cable structures under moving loads, particularly on the catenary-pantograph dynamic interaction. This work firstly describes the modeling of a finite element moving mesh which integrally moves over the contact wire following the pantograph along the whole catenary, prior focusing on its comparison against the classical finite element mesh. The case study corresponds to the standard EN-50318 one, whose results fulfill the ranges proposed by this validation rule. The main advantage of the moving mesh method is presented in the falling of computational costs about 4 times lower than the classic model with similar precision.Peer Reviewe

    Simulation of moving loads on structures using a moving finite element mesh

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    En este artículo se presenta una metodología para analizar la respuesta dinámica de estructuras sometidas a cargas móviles. Para ello se ha desarrollado un algoritmo de mallado adaptativo de elementos finitos que se mueve de forma solidaria a la carga móvil que actúa sobre la estructura. El algoritmo de mallado móvil se ha validado con la solución analítica de una carga móvil que recorre una viga simplemente apoyada.This paper presents a methodology to analyze the dynamic behavior of structures under moving loads. A finite element moving mesh algorithm has been developed in order to integrally move a part of the mesh following a moving load. This algorithm has been validated with the analytical solution of a moving load applied on a simply supported beam.Peer Reviewe

    Influence of Track Irregularities in the Catenary-Pantograph Dynamic Interaction

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    This paper presents an advanced pantograph-catenary-vehicle-track model, which allows us to analyze the vertical dynamics of the complete system. The developed model is able to evaluate the displacements and the contact force generated in the catenary-pantograph as well as the wheel-track interactions. Nevertheless, this paper focuses on the possible influence of track irregularities on the catenary-pantograph dynamic interaction. From a power spectral density function of the track irregularities, 180 track profiles and their respective catenary-pantograph-vehicle-track simulations have been generated. The wide range of results allows us to obtain some conclusions about the influence of the track profile in the catenary-pantograph behavior

    Time and "angular" dependent backgrounds from stationary axisymmetric solutions

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    Backgrounds depending on time and on "angular" variable, namely polarized and unpolarized S1×S2S^1 \times S^2 Gowdy models, are generated as the sector inside the horizons of the manifold corresponding to axisymmetric solutions. As is known, an analytical continuation of ordinary DD-branes, iDiD-branes allows one to find SS-brane solutions. Simple models have been constructed by means of analytic continuation of the Schwarzchild and the Kerr metrics. The possibility of studying the ii-Gowdy models obtained here is outlined with an eye toward seeing if they could represent some kind of generalized SS-branes depending not only on time but also on an ``angular'' variable.Comment: 24 pages, 5 figures, corrected typos, references adde

    Mechanical and Thermal Properties of Polyvinyl Chloride Plasticized with Natural Fatty Acid Esters

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    From an industrial point of view, the use of new nontoxic and biodegradable plasticizers coming from natural resources is an interesting alternative to traditional plasticizers based on phthalates. In this study, two types of epoxidized fatty acids esters (EFAE) with different molecular weights have been used in order to produce flexible PVC with low toxicity. Different amounts of EFAE 201 and 401 have been considered in this study. Mechanical and thermal properties have been determined and morphology of fracture surface has been studied by scanning electron microscopy.This work was supported by the "Ministerio de Ciencia e Innovacion" [Grant number IPT-310000-2010-37] and the "Universitat Politecnica de Valencia" [Grant number PAID 06-10 Ref: 003-300].Fenollar Gimeno, OÁ.; García Sanoguera, D.; Sánchez Nacher, L.; Boronat Vitoria, T.; López Martínez, J.; Balart Gimeno, RA. (2013). Mechanical and Thermal Properties of Polyvinyl Chloride Plasticized with Natural Fatty Acid Esters. Polymer-Plastics Technology and Engineering. 52(8):761-767. https://doi.org/10.1080/03602559.2013.763352S761767528Zhao, R., Neighbour, G., Deutz, P., & McGuire, M. (2012). Materials selection for cleaner production: An environmental evaluation approach. Materials & Design, 37, 429-434. doi:10.1016/j.matdes.2012.01.014Biedermann-Brem, S., Biedermann, M., Fiselier, K., & Grob, K. (2005). Compositional GC-FID analysis of the additives to PVC, focusing on the gaskets of lids for glass jars. Food Additives and Contaminants, 22(12), 1274-1284. doi:10.1080/02652030500309426Braun, D. (2001). PVC ? origin, growth, and future. Journal of Vinyl and Additive Technology, 7(4), 168-176. doi:10.1002/vnl.10288Summers, J. W. (1997). A review of vinyl technology. Journal of Vinyl and Additive Technology, 3(2), 130-139. doi:10.1002/vnl.10179Islam, R., Islam, T., Nigar, F., Saha, S., Tapash, A., Sharmin, N., … Zaman, H. U. (2011). Fabrication and Mechanical Characterization of Jute Fabrics: Reinforced Polyvinyl Chloride/Polypropylene Hybrid Composites. International Journal of Polymeric Materials, 60(8), 576-590. doi:10.1080/00914037.2010.531822Khan, R. A., Sharmin, N., Khan, M. A., Das, A. K., Dey, K., Saha, S., … Saha, M. (2011). Comparative Studies of Mechanical and Interfacial Properties Between Jute Fiber/PVC and E-Glass Fiber/PVC Composites. Polymer-Plastics Technology and Engineering, 50(2), 153-159. doi:10.1080/03602559.2010.531422Hassan, A., Akbari, A., Hing, N. K., & Ratnam, C. T. (2012). Mechanical and Thermal Properties of ABS/PVC Composites: Effect of Particles Size and Surface Treatment of Ground Calcium Carbonate. Polymer-Plastics Technology and Engineering, 51(5), 473-479. doi:10.1080/03602559.2011.651242Zhu, G., Liu, Y., & Wang, F. (2012). Surface Morphology and Properties of Rigid Poly(γ-benzylL-glutamate) Membrane Modified by Flexible Poly(Vinyl Chloride). International Journal of Polymeric Materials, 61(10), 737-747. doi:10.1080/00914037.2011.610044KAWAMURA, Y., KANNO, S., MUTSUGA, M., & TANAMOTO, K. (2006). Determination of Epoxidized Soybean Oil in Bottled Foods. Journal of the Food Hygienic Society of Japan (Shokuhin Eiseigaku Zasshi), 47(6), 243-248. doi:10.3358/shokueishi.47.243Marcilla, A., Garcia, S., & Garcia-Quesada, J. C. (2008). Migrability of PVC plasticizers. Polymer Testing, 27(2), 221-233. doi:10.1016/j.polymertesting.2007.10.007Wang, Q., & Storm, B. K. (2005). Separation and analysis of low molecular weight plasticizers in poly(vinyl chloride) tubes. Polymer Testing, 24(3), 290-300. doi:10.1016/j.polymertesting.2004.12.002Llop, C., Manrique, A., Navarro, R., Mijangos, C., & Reinecke, H. (2011). Control of the migration behavior of slip agents in polyolefin-based films. Polymer Engineering & Science, 51(9), 1763-1769. doi:10.1002/pen.21963Pedersen, G. A., Jensen, L. K., Fankhauser, A., Biedermann, S., Petersen, J. H., & Fabech, B. (2008). Migration of epoxidized soybean oil (ESBO) and phthalates from twist closures into food and enforcement of the overall migration limit. Food Additives & Contaminants: Part A, 25(4), 503-510. doi:10.1080/02652030701519088Jimenez, A., Lopez, J., Iannoni, A., & Kenny, J. M. (2001). Formulation and mechanical characterization of PVC plastisols based on low-toxicity additives. Journal of Applied Polymer Science, 81(8), 1881-1890. doi:10.1002/app.1621Shea, K. M. (2003). Pediatric Exposure and Potential Toxicity of Phthalate Plasticizers. PEDIATRICS, 111(6), 1467-1474. doi:10.1542/peds.111.6.1467Boudhani, H., Lainé, C., Fulchiron, R., Bounor-Legaré, V., & Cassagnau, P. (2009). Viscoelasticity and mechanical properties of reactive PVC plastisols. Polymer Engineering & Science, 49(6), 1089-1098. doi:10.1002/pen.21356Wang, M. Y., Zhou, N. Q., & Wen, S. P. (2009). The Effect of Concentrations of Modifying Agent and Plasticizer on Cell Morphology of PVC Microcellular Foam. Polymer-Plastics Technology and Engineering, 48(3), 303-309. doi:10.1080/03602550802675678Yang, B., Bai, Y., & Cao, Y. (2010). Effects of inorganic nano-particles on plasticizers migration of flexible PVC. Journal of Applied Polymer Science, 115(4), 2178-2182. doi:10.1002/app.31310Kilinç, S., İyim, T. B., Emik, S., & Özgümüş, S. (2005). Recycling of Waste PET: Usage as Secondary Plasticizer for PVC. Polymer-Plastics Technology and Engineering, 44(8-9), 1379-1388. doi:10.1080/03602550500208228Audic, J.-L., Reyx, D., & Brosse, J.-C. (2003). Migration of additives from food grade polyvinyl chloride (PVC) films: Effect of plasticization by polymeric modifiers instead of conventional plasticizers. Journal of Applied Polymer Science, 89(5), 1291-1299. doi:10.1002/app.12240Fankhauser-Noti, A., Biedermann-Brem, S., & Grob, K. (2006). PVC plasticizers/additives migrating from the gaskets of metal closures into oily food: Swiss market survey June 2005. European Food Research and Technology, 223(4), 447-453. doi:10.1007/s00217-005-0223-7Sharma, V., & Kundu, P. P. (2008). Condensation polymers from natural oils. Progress in Polymer Science, 33(12), 1199-1215. doi:10.1016/j.progpolymsci.2008.07.004Benaniba, M. ., Belhaneche-Bensemra, N., & Gelbard, G. (2001). Stabilizing effect of epoxidized sunflower oil on the thermal degradation of poly(vinyl chloride). Polymer Degradation and Stability, 74(3), 501-505. doi:10.1016/s0141-3910(01)00170-7Atek, D., Belhaneche-Bensemra, N., & Turki, M. (2010). Migration of Epoxidized Sunflower Oil and Dioctyl Phthalate from Rigid and Plasticized Poly(vinyl chloride). International Journal of Polymeric Materials, 59(5), 342-352. doi:10.1080/00914030903478909Ghiou, N., & Benaniba, M. T. (2010). The Effect of Epoxidized Sunflower Oil on the Miscibility of Plasticized PVC/NBR Blends. International Journal of Polymeric Materials, 59(7), 463-474. doi:10.1080/00914031003627007Taghizadeh, M. T., Nalbandi, N., & Bahadori, A. (2008). Stabilizing effect of epoxidized sunflower oil as a secondary stabilizer for Ca/Hg stabilized PVC. Express Polymer Letters, 2(1), 65-76. doi:10.3144/expresspolymlett.2008.9Fenollar, O., Garcia-Sanoguera, D., Sanchez-Nacher, L., Lopez, J., & Balart, R. (2010). Effect of the epoxidized linseed oil concentration as natural plasticizer in vinyl plastisols. Journal of Materials Science, 45(16), 4406-4413. doi:10.1007/s10853-010-4520-6Galià, M., de Espinosa, L. M., Ronda, J. C., Lligadas, G., & Cádiz, V. (2010). Vegetable oil-based thermosetting polymers. European Journal of Lipid Science and Technology, 112(1), 87-96. doi:10.1002/ejlt.200900096Nandanan, V., Joseph, R., & Francis, D. J. (1996). Linseed Oil as a Multipurpose Ingredient in NBR Vulcanizate. Journal of Elastomers & Plastics, 28(4), 326-334. doi:10.1177/009524439602800404Fenollar, O., García, D., Sánchez, L., López, J., & Balart, R. (2009). Optimization of the curing conditions of PVC plastisols based on the use of an epoxidized fatty acid ester plasticizer. European Polymer Journal, 45(9), 2674-2684. doi:10.1016/j.eurpolymj.2009.05.029Fenollar, O., Sanchez-Nacher, L., Garcia-Sanoguera, D., López, J., & Balart, R. (2009). The effect of the curing time and temperature on final properties of flexible PVC with an epoxidized fatty acid ester as natural-based plasticizer. Journal of Materials Science, 44(14), 3702-3711. doi:10.1007/s10853-009-3495-7Crespo, J. E., Balart, R., Sanchez, L., & López, J. (2007). Substitution of di(2-ethylhexyl) phthalate by di(isononyl) cyclohexane-1,2-dicarboxylate as a plasticizer for industrial vinyl plastisol formulations. Journal of Applied Polymer Science, 104(2), 1215-1220. doi:10.1002/app.2576

    “Publishing Is Mystical”: The Latinx Caucus Bibliography, Top-Tier Journals, and Minority Scholarship

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    In 2014, members of the NCTE/CCCC Latinx Caucus began contributing citations to a shared Google Document (GDoc) that suggested a relatively significant contribution of scholarship to the field of Rhetoric and Composition studies. Scholars of color have argued that rhetoric and composition scholarship fails to represent diversity in academic publications (Baca; Banks; Jones Royster; Pimentel; Ruíz). This study examines statistical data arrived at through analysis of the NCTE/CCCC Latinx Caucus Bibliography, with survey and interview data from Latinx scholars providing important context about publishing for people of color

    MYC activation impairs cell-intrinsic IFNγ signaling and confers resistance to anti-PD1/PD-L1 therapy in lung cancer

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    Elucidating the adaptive mechanisms that prevent host immune response in cancer will help predict efficacy of anti-programmed death-1 (PD1)/L1 therapies. Here, we study the cell-intrinsic response of lung cancer (LC) to interferon-y (IFNy), a cytokine that promotes immunoresponse and modulates programmed death-ligand 1 (PD-L1) levels. We report complete refractoriness to IFNy in a subset of LCs as a result of JAK2 or IFNGR1 inactivation. A submaximal response affects another subset that shows constitutive low levels of IFNy-stimulated genes (IySGs) coupled with decreased H3K27ac (histone 3 acetylation at lysine 27) depo-sition and promoter hypermethylation and reduced IFN regulatory factor 1 (IRF1) recruitment to the DNA on IFNy stimulation. Most of these are neuroendocrine small cell LCs (SCLCs) with oncogenic MYC/MYCL1/ MYCN. The oncogenic activation of MYC in SCLC cells downregulates JAK2 and impairs IySGs stimulation by IFNy. MYC amplification tends to associate with a worse response to anti-PD1/L1 therapies. Hence alterations affecting the JAK/STAT pathway and MYC activation prevent stimulation by IFNy and may predict anti-PD1/L1 efficacy in LC

    SMARCA4 deficient tumours are vulnerable to KDM6A/UTX and KDM6B/JMJD3 blockade

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    The authors thank Isabel Bartolessis (Cancer Genetics Group) at IJC for technical assistance. This work was supported by the Spanish Ministry of Economy and CompetitivityMINECO (grant number SAF-2017-82186R, to M.S.-C., and grant PI19/01320 to A. Villanueva) and from the Fundacion Cientifica of the Asociacion Espanola Contra el Cancer (AECC) (grant number GCB14142170MONT) to M.S.-C. A. Villanueva is also funded by the Department of Health of the Generalitat de Catalunya (2014SGR364). O.A. R. received a Juan de la Cierva postdoctoral contract (grant No. IJCI-2016-28201, until November 2019) and an AECC research contract (INVES19045ROME from December 2019). A. Vilarrubi, P.L. and A.A. are supported by pre-doctoral contracts from the Spanish MINECO (FPI-fellowship: PRE2018-084624, BES-2015-072204 and FPU17/00067). M.S. was supported by a Rio Hortega contract from the Instituto de Salud Carlos III (CM17/00180). L.F. received a European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Actions grant agreement, number 799850.Despite the genetic inactivation of SMARCA4, a core component of the SWI/SNF-complex commonly found in cancer, there are no therapies that effectively target SMARCA4-deficient tumours. Here, we show that, unlike the cells with activated MYC oncogene, cells with SMARCA4 inactivation are refractory to the histone deacetylase inhibitor, SAHA, leading to the aberrant accumulation of H3K27me3. SMARCA4-mutant cells also show an impaired transactivation and significantly reduced levels of the histone demethylases KDM6A/UTX and KDM6B/JMJD3, and a strong dependency on these histone demethylases, so that its inhibition compromises cell viability. Administering the KDM6 inhibitor GSK-J4 to mice orthotopically implanted with SMARCA4-mutant lung cancer cells or primary small cell carcinoma of the ovary, hypercalcaemic type (SCCOHT), had strong anti-tumour effects. In this work we highlight the vulnerability of KDM6 inhibitors as a characteristic that could be exploited for treating SMARCA4-mutant cancer patients.Spanish Ministry of Economy and Competitivity-MINECO SAF-2017-82186R PI19/01320Fundacion Cientifica of the Asociacion Espanola Contra el Cancer (AECC) GCB14142170MONTDepartment of Health of the Generalitat de Catalunya 2014SGR364Juan de la Cierva postdoctoral contract IJCI-2016-28201AECC research contract INVES19045ROMESpanish MINECO PRE2018-084624 BES-2015-072204 FPU17/00067Instituto de Salud Carlos III European Commission CM17/00180European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Actions grant agreement 79985

    MASked-unconTrolled hypERtension management based on office BP or on ambulatory blood pressure measurement (MASTER) Study: a randomised controlled trial protocol.

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    Masked uncontrolled hypertension (MUCH) carries an increased risk of cardiovascular (CV) complications and can be identified through combined use of office (O) and ambulatory (A) blood pressure (BP) monitoring (M) in treated patients. However, it is still debated whether the information carried by ABPM should be considered for MUCH management. Aim of the MASked-unconTrolled hypERtension management based on OBP or on ambulatory blood pressure measurement (MASTER) Study is to assess the impact on outcome of MUCH management based on OBPM or ABPM

    Sentinel lymph node mapping and intraoperative assessment in a prospective, international, multicentre, observational trial of patients with cervical cancer: The SENTIX trial

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    Background: SENTIX (ENGOT-CX2/CEEGOG-CX1) is an international, multi centre, prospective observational trial evaluating sentinel lymph node (SLN) biopsy without pelvic lymph node dissection in patients with early-stage cervical cancer. We report the final preplanned analysis of the secondary end-points: SLN mapping and outcomes of intraoperative SLN pathology. Methods: Forty-seven sites (18 countries) with experience of SLN biopsy participated in SENTIX. We preregistered patients with stage IA1/lymphovascular space invasion-positive to IB2 (4 cm or smaller or 2 cm or smaller for fertility-sparing treatment) cervical cancer without suspicious lymph nodes on imaging before surgery. SLN frozen section assessment and pathological ultrastaging were mandatory. Patients were registered postoperatively if SLN were bilaterally detected in the pelvis, and frozen sections were negative. Trial registration: ClinicalTrials.gov (NCT02494063). Results: We analysed data for 395 preregistered patients. Bilateral detection was achieved in 91% (355/395), and it was unaffected by tumour size, tumour stage or body mass index, but it was lower in older patients, in patients who underwent open surgery, and in sites with fewer cases. No SLN were found outside the seven anatomical pelvic regions. Most SLN and positive SLN were localised below the common iliac artery bifurcation. Single positive SLN above the iliac bifurcation were found in 2% of cases. Frozen sections failed to detect 54% of positive lymph nodes (pN1), including 28% of cases with macrometastases and 90% with micrometastases. Interpretation: SLN biopsy can achieve high bilateral SLN detection in patients with tumours of 4 cm or smaller. At experienced centres, all SLN were found in the pelvis, and most were located below the iliac vessel bifurcation. SLN frozen section assessment is an unreliable tool for intraoperative triage because it only detects about half of N1 cases. (C) 2020 The Author(s). Published by Elsevier Ltd
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