1,536 research outputs found

    Study of radial heat transport in W7-X using the transfer entropy

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    Autor colectivo: W7-X TeamIn this work, we analyze data obtained using the electron cyclotron emission radiometer at the Wendelstein 7-X stellarator using a relatively new technique: the transfer entropy. Thus, we detect the propagation of information and find that it occurs in a stepwise fashion: we observe both 'trapping zones' and radial 'jumps', when the information is apparently skipping over intermediate positions. Using scans of the rotational transform, we observe that the 'trapping zones' appear to be associated with rational surfaces. Power scan experiments show that these 'jumps' increase in importance when power is increased, thus enhancing the effective diffusivity. The observations are interpreted in terms of a resistive magneto-hydrodynamic model, which displays behavior similar to the experimental results. The 'trapping zones' are explained in terms of zonal flows associated with rational surfaces, while the 'jumps' are ascribed to mode coupling effects, i.e. the transmission of turbulent energy via the magnetic field

    Identification of circulating microRNA profiles associated with pulmonary function and radiologic features in survivors of SARS-CoV-2-induced ARDS

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    ABSTRACT There is a limited understanding of the pathophysiology of postacute pulmonary sequelae in severe COVID-19. The aim of current study was to define the circulating microRNA (miRNA) profiles associated with pulmonary function and radiologic features in survivors of SARS-CoV-2-induced ARDS. The study included patients who developed ARDS secondary to SARS-CoV-2 infection (n=167) and a group of infected patients who did not develop ARDS (n=33). Patients were evaluated 3 months after hospital discharge. The follow-up included a complete pulmonary evaluation and chest computed tomography. Plasma miRNA profiling was performed using RT-qPCR. Random forest was used to construct miRNA signatures associated with lung diffusing capacity for carbon monoxide (DLCO) and total severity score (TSS). Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses were conducted. DLCO<80% predicted was observed in 81.8% of the patients. TSS showed a median [P25;P75] of 5 [2;8]. The miRNA model associated with DLCO comprised miR-17-5p, miR-27a-3p, miR-126-3p, miR-146a-5p and miR-495-3p. Concerning radiologic features, a miRNA signature composed by miR-9-5p, miR-21-5p, miR-24-3p and miR-221-3p correlated with TSS values. These associations were not observed in the non-ARDS group. KEGG pathway and GO enrichment analyses provided evidence of molecular mechanisms related not only to profibrotic or anti-inflammatory states but also to cell death, immune response, hypoxia, vascularization, coagulation and viral infection. In conclusion, diffusing capacity and radiological features in survivors from SARS-CoV-2-induced ARDS are associated with specific miRNA profiles. These findings provide novel insights into the possible molecular pathways underlying the pathogenesis of pulmonary sequelae. Trial registration: ClinicalTrials.gov identifier: NCT04457505.. Trial registration: ISRCTN.org identifier: ISRCTN16865246..This work is supported by Instituto de Salud Carlos III (COV20/00110), co-funded by European Regional Development Fund (ERDF)/“A way to make Europe”. CIBERES is an initiative of the Instituto de Salud Carlos III. CIBERES is an initiative of the Instituto de Salud Carlos III. Suported by: Programa de donaciones "estar preparados" UNESPA (Madrid, Spain) and FundaciĂłn Francisco Soria Melguizo (Madrid, Spain).. Finançat per La FundaciĂł La MaratĂł de TV3, projecte amb codi 202108-30/-31. COVIDPONENT is funded by Institut CatalĂ  de la Salut and GestiĂł de Serveis Sanitaris. MM is the recipient of a predoctoral fellowship (PFIS: FI21/00187) from Instituto de Salud Carlos III. MCGH is the recipient of a predoctoral fellowship from “University of Lleida”. DdGC has received financial support from Instituto de Salud Carlos III (Miguel Servet 2020: CP20/00041), co-funded by the European Social Fund (ESF)/“Investing in your future”. ENL and GL were funded by COVID1005 and ACT210085 from National Agency of Investigation & Development (ANID), Chile."Article signat per 27 autors/es: MarĂ­a C. GarcĂ­a-Hidalgo, Jessica GonzĂĄlez, IvĂĄn D. BenĂ­tez, Paola Carmona, Sally Santisteve, Manel PĂ©rez-Pons, Anna MoncusĂ­-Moix, Clara Gort-Paniello, FĂĄtima RodrĂ­guez-Jara, Marta Molinero, Thalia Belmonte, Gerard Torres, Gonzalo Labarca, Estefania Nova-Lamperti, JesĂșs Caballero, JesĂșs F. Bermejo-Martin, AdriĂĄn Ceccato, Laia FernĂĄndez-Barat, Ricard Ferrer, Dario Garcia-Gasulla, Rosario MenĂ©ndez, Ana Motos ,Oscar Peñuelas, Jordi Riera, Antoni Torres, Ferran BarbĂ©, David de Gonzalo-Calvo & on behalf of the CIBERESUCICOVID Project (COV20/00110 ISCIII)"Postprint (published version

    Recent Technological Developments on LGAD and iLGAD Detectors for Tracking and Timing Applications

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    This paper reports the last technological development on the Low Gain Avalanche Detector (LGAD) and introduces a new architecture of these detectors called inverse-LGAD (iLGAD). Both approaches are based on the standard Avalanche Photo Diodes (APD) concept, commonly used in optical and X-ray detection applications, including an internal multiplication of the charge generated by radiation. The multiplication is inherent to the basic n++-p+-p structure, where the doping profile of the p+ layer is optimized to achieve high field and high impact ionization at the junction. The LGAD structures are optimized for applications such as tracking or timing detectors for high energy physics experiments or medical applications where time resolution lower than 30 ps is required. Detailed TCAD device simulations together with the electrical and charge collection measurements are presented through this work.Comment: Keywords: silicon detectors, avalanche multiplication, timing detectors, tracking detectors. 8 pages. 8 Figure

    Statistical analysis of the ion flux to the JET outer wall

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    Statistical analysis of the ion flux to the JET outer-wall is conducted in outer-wall limiter mounted Langmuir probe (OLP) time-series across a wide range of plasma current and line-averaged density during Ohmically heated horizontal target L-mode plasmas. The mean, ÎŒ, and the standard deviation, σ, of the ion-saturation current measured by the OLP show systematic variation with plasma current and density. Both increase as either plasma current decreases and/or density increases. Upon renormalization, achieved by subtraction of ÎŒ and rescaling by σ, the probability distribution functions (PDFs) of each signal collapse approximately onto a single curve. The shape of the curve deviates from a Γ distribution in the tail of the PDF and is better described by a log-normal distribution. The invariance in the shape of the PDF, which occurs over approximately four decades of the ordinate, is shown to be the result of a balance between the duration time of the average burst wave-form, τd and the waiting time between bursts, τw. This implies that the intermittency parameter, τd/τw , can be considered constant at the JET outer wall during horizontal target Ohmic L-mode operation. This result may be important both for model validation and prediction

    Transcriptional dissection of pancreatic tumors engrafted in mice.

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    BACKGROUND: Engraftment of primary pancreas ductal adenocarcinomas (PDAC) in mice to generate patient-derived xenograft (PDX) models is a promising platform for biological and therapeutic studies in this disease. However, these models are still incompletely characterized. Here, we measured the impact of the murine tumor environment on the gene expression of the engrafted human tumoral cells. METHODS: We have analyzed gene expression profiles from 35 new PDX models and compared them with previously published microarray data of 18 PDX models, 53 primary tumors and 41 cell lines from PDAC. The results obtained in the PDAC system were further compared with public available microarray data from 42 PDX models, 108 primary tumors and 32 cell lines from hepatocellular carcinoma (HCC). We developed a robust analysis protocol to explore the gene expression space. In addition, we completed the analysis with a functional characterization of PDX models, including if changes were caused by murine environment or by serial passing. RESULTS: Our results showed that PDX models derived from PDAC, or HCC, were clearly different to the cell lines derived from the same cancer tissues. Indeed, PDAC- and HCC-derived cell lines are indistinguishable from each other based on their gene expression profiles. In contrast, the transcriptomes of PDAC and HCC PDX models can be separated into two different groups that share some partial similarity with their corresponding original primary tumors. Our results point to the lack of human stromal involvement in PDXs as a major factor contributing to their differences from the original primary tumors. The main functional differences between pancreatic PDX models and human PDAC are the lower expression of genes involved in pathways related to extracellular matrix and hemostasis and the up- regulation of cell cycle genes. Importantly, most of these differences are detected in the first passages after the tumor engraftment. CONCLUSIONS: Our results suggest that PDX models of PDAC and HCC retain, to some extent, a gene expression memory of the original primary tumors, while this pattern is not detected in conventional cancer cell lines. Expression changes in PDXs are mainly related to pathways reflecting the lack of human infiltrating cells and the adaptation to a new environment. We also provide evidence of the stability of gene expression patterns over subsequent passages, indicating early phases of the adaptation process

    Zonal flows and long-distance correlations during the formation of the edge shear layer in the TJ-II stellarator

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    A theoretical interpretation is given for the observed long-distance correlations in potential fluctuations in TJ-II. The value of the correlation increases above the critical point of the transition for the emergence of the plasma edge shear flow layer. Mean (i.e. surface averaged, zero-frequency) sheared flows cannot account for the experimental results. A model consisting of four envelope equations for the fluctuation level, the mean flow shear, the zonal flow amplitude shear, and the averaged pressure gradient is proposed. It is shown that the presence of zonal flows is essential to reproduce the main features of the experimental observations.Comment: 19 pages, 7 figure

    Granular packings of elongated faceted particles deposited under gravity

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    We report experimental and theoretical results of the effect that particle shape has on the packing properties of granular materials. We have systematically measured the particle angular distribution, the cluster size distribution and the stress profiles of ensembles of faceted elongated particles deposited in a bidimensional box. Stress transmission through this granular system has been numerically simulated using a two-dimensional model of irregular particles. For grains of maximum symmetry (squares), the stress propagation localizes and forms chain-like forces analogous to those observed for granular materials composed of spheres. For thick layers of grains, a pressure saturation is observed for deposit depths beyond a characteristic length. This scenario correlates with packing morphology and can be understood in terms of stochastic models of aggregation and random multiplicative processes. As grains elongate and lose their symmetry, stress propagation is strongly affected. Lateral force transmission becomes less favored than vertical transfer, and hence, an increase in the pressure develops with depth, hindering force saturation

    NĂ­veis de desfolha tolerados na cultura da soja sem a ocorrĂȘncia de prejuĂ­zos Ă  produtividade.

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    NĂ­vel de ação e o MIP-Soja. Ensaios com injĂșria na fase inicial da lavoura: Londrina, PR ? Safras 2001/2002 e 2002/2003. Ensaios com diferentes nĂ­veis de desfolha em diferentes fases do desenvolvimento: NĂŁo-Me-Toque-RS e Sorriso-MT ? Safra 2008/2009. Ensaios com diferentes nĂ­veis de desfolha contĂ­nua durante diferentes fases do desenvolvimento: Morrinhos, GO ? Safra 2009/2010. Resultados obtidos que comprovam a segurança dos nĂ­veis de ação recomendados. ConsideraçÔes finais.bitstream/item/31176/1/CT79VE.pd

    Multimodal Treatment Eliminates Cancer Stem Cells and Leads to Long-Term Survival in Primary Human Pancreatic Cancer Tissue Xenografts.

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    Copyright: 2013 Hermann et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.PURPOSE: In spite of intense research efforts, pancreatic ductal adenocarcinoma remains one of the most deadly malignancies in the world. We and others have previously identified a subpopulation of pancreatic cancer stem cells within the tumor as a critical therapeutic target and additionally shown that the tumor stroma represents not only a restrictive barrier for successful drug delivery, but also serves as a paracrine niche for cancer stem cells. Therefore, we embarked on a large-scale investigation on the effects of combining chemotherapy, hedgehog pathway inhibition, and mTOR inhibition in a preclinical mouse model of pancreatic cancer. EXPERIMENTAL DESIGN: Prospective and randomized testing in a set of almost 200 subcutaneous and orthotopic implanted whole-tissue primary human tumor xenografts. RESULTS: The combined targeting of highly chemoresistant cancer stem cells as well as their more differentiated progenies, together with abrogation of the tumor microenvironment by targeting the stroma and enhancing tissue penetration of the chemotherapeutic agent translated into significantly prolonged survival in preclinical models of human pancreatic cancer. Most pronounced therapeutic effects were observed in gemcitabine-resistant patient-derived tumors. Intriguingly, the proposed triple therapy approach could be further enhanced by using a PEGylated formulation of gemcitabine, which significantly increased its bioavailability and tissue penetration, resulting in a further improved overall outcome. CONCLUSIONS: This multimodal therapeutic strategy should be further explored in the clinical setting as its success may eventually improve the poor prognosis of patients with pancreatic ductal adenocarcinoma
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