92 research outputs found

    Integration of UAV photogrammetry and SPH modelling of fluids to study runoff on real terrains

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    Roads can experience runoff problems due to the intense rain discharge associated to severe storms. Two advanced tools are combined to analyse the interaction of complex water flows with real terrains. UAV (Unmanned Aerial Vehicle) photogrammetry is employed to obtain accurate topographic information on small areas, typically on the order of a few hectares. The Smoothed Particle Hydrodynamics (SPH) technique is applied by means of the DualSPHysics model to compute the trajectory of the water flow during extreme rain events. The use of engineering solutions to palliate flood events is also analysed. The study case simulates how the collected water can flow into a close road and how precautionary measures can be effective to drain water under extreme conditions. The amount of water arriving at the road is calculated under different protection scenarios and the efficiency of a ditch is observed to decrease when sedimentation reduces its depth.Ministerio de Economía y Competitividad | Ref. BIA2012-38676- C03-0

    Deploying unsupervised clustering analysis to derive clinical phenotypes and risk factors associated with mortality risk in 2022 critically ill patients with COVID-19 in Spain

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    Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Fenotips; Factors de risc; Infecció greu per SARS-CoV-2Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Fenotipos; Factores de riesgo; Infección grave por SARS-CoV-2Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Phenotypes; Risk factors; Severe SARS-CoV-2 infectionBackground The identification of factors associated with Intensive Care Unit (ICU) mortality and derived clinical phenotypes in COVID-19 patients could help for a more tailored approach to clinical decision-making that improves prognostic outcomes. Methods Prospective, multicenter, observational study of critically ill patients with confirmed COVID-19 disease and acute respiratory failure admitted from 63 ICUs in Spain. The objective was to utilize an unsupervised clustering analysis to derive clinical COVID-19 phenotypes and to analyze patient’s factors associated with mortality risk. Patient features including demographics and clinical data at ICU admission were analyzed. Generalized linear models were used to determine ICU morality risk factors. The prognostic models were validated and their performance was measured using accuracy test, sensitivity, specificity and ROC curves. Results The database included a total of 2022 patients (mean age 64 [IQR 5–71] years, 1423 (70.4%) male, median APACHE II score (13 [IQR 10–17]) and SOFA score (5 [IQR 3–7]) points. The ICU mortality rate was 32.6%. Of the 3 derived phenotypes, the A (mild) phenotype (537; 26.7%) included older age ( 65 years), high severity of illness and a higher likelihood of development shock. Crude ICU mortality was 20.3%, 25% and 45.4% for A, B and C phenotype respectively. The ICU mortality risk factors and model performance differed between whole population and phenotype classifications. Conclusion The presented machine learning model identified three clinical phenotypes that significantly correlated with host-response patterns and ICU mortality. Different risk factors across the whole population and clinical phenotypes were observed which may limit the application of a “one-size-fits-all” model in practice.This study was supported by the Spanish Intensive Care Society (SEMICYUC) and Ricardo Barri Casanovas Foundation. The study sponsors have no role in the study design, data collection, data analysis, data interpretation, or writing of the report

    Structural determination of Bi-doped magnetite multifunctional nanoparticles for contrast imaging

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    To determine with precision how Bi atoms are distributed in Bi-doped iron oxide nanoparticles their structural characterization has been carried out by X-ray absorption spectroscopy (XAS) recorded at the K edge of Fe and at the L edge of Bi. The inorganic nanoparticles are nominally hybrid structures integrating an iron oxide core and a bismuth oxide shell. Fe K-edge XAS indicates the formation of a structurally ordered, non-stoichiometric magnetite (FeO) phase for all the nanoparticles. The XAS spectra show that, in the samples synthesized by precipitation in aqueous media and laser pyrolysis, the Bi atoms neither enter into the iron oxide spinel lattice nor form any other mixed Bi-Fe oxides. No modification of the local structure around the Fe atoms induced by the Bi atoms is observed at the Fe K edge. In addition, contrary to expectations, our results indicate that the Bi atoms do not form a well-defined Bi oxide structure. The XAS study at the Bi L edge indicates that the environment around Bi atoms is highly disordered and only a first oxygen coordination shell is observed. Indefinite [BiO(OH)] units (isolated or aggregated forming tiny amorphous clusters) bonded through hydroxyl bridges to the nanoparticle, rather than a well defined BiO shell, surround the nanoparticle. On the other hand, the XAS study indicates that, in the samples synthesized by thermal decomposition, the Bi atoms are embedded in a longer range ordered structure showing the first and second neighbors

    Design strategies for shape-controlled magnetic iron oxide nanoparticles

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    Ferrimagnetic iron oxide nanoparticles (magnetite or maghemite) have been the subject of an intense research, not only for fundamental research but also for their potentiality in a widespread number of practical applications. Most of these studies were focused on nanoparticles with spherical morphology but recently there is an emerging interest on anisometric nanoparticles. This review is focused on the synthesis routes for the production of uniform anisometric magnetite/maghemite nanoparticles with different morphologies like cubes, rods, disks, flowers and many others, such as hollow spheres, worms, stars or tetrapods. We critically analyzed those procedures, detected the key parameters governing the production of these nanoparticles with particular emphasis in the role of the ligands in the final nanoparticle morphology. The main structural and magnetic features as well as the nanotoxicity as a function of the nanoparticle morphology are also described. Finally, the impact of each morphology on the different biomedical applications (hyperthermia, magnetic resonance imaging and drug delivery) are analysed in detail. We would like to dedicate this work to Professor Carlos J. Serna, Instituto de Ciencia de Materiales de Madrid, ICMM/CSIC, for his outstanding contribution in the field of monodispersed colloids and iron oxide nanoparticles. We would like to express our gratitude for all these years of support and inspiration on the occasion of his retirement

    Elucidating Individual Magnetic Contributions in Bi-Magnetic Fe3O4/Mn3O4 Core/Shell Nanoparticles by Polarized Powder Neutron Diffraction

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    Heterogeneous bi-magnetic nanostructured systems have had a sustained interest during the last decades owing to their unique magnetic properties and the wide range of derived potential applications. However, elucidating the details of their magnetic properties can be rather complex. Here, a comprehensive study of FeO/MnO core/shell nanoparticles using polarized neutron powder diffraction, which allows disentangling the magnetic contributions of each of the components, is presented. The results show that while at low fields the FeO and MnO magnetic moments averaged over the unit cell are antiferromagnetically coupled, at high fields, they orient parallel to each other. This magnetic reorientation of the MnO shell moments is associated with a gradual evolution with the applied field of the local magnetic susceptibility from anisotropic to isotropic. Additionally, the magnetic coherence length of the FeO cores shows some unusual field dependence due to the competition between the antiferromagnetic interface interaction and the Zeeman energies. The results demonstrate the great potential of the quantitative analysis of polarized neutron powder diffraction for the study of complex multiphase magnetic materials

    Mapping mechanical stress in curved epithelia of designed size and shape

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    We thank C. Pérez-González, N. Castro, and all of the members of the Roca-Cusachs, Arroyo, and Trepat laboratories for their discussions and support. This work was supported by: Generalitat de Catalunya (Agaur, SGR-2021-01425 to X.T., SGR-2021-00523 to R.S., the CERCA Programme, and “ICREA Academia” award to M.A. and P.R-C.); Spanish Ministry for Science and Innovation MICCINN/FEDER (PID2021- 128635NB-I00, MCIN/AEI/ 10.13039/501100011033 and “ERDF-EU A way of making Europe” to X.T., PID2019-110949GB-I00 to M.A., PID2019- 110298GB-I00 to P.R.-C., PID2021-128674OB-I00, RTI2018-101256-J-I00, and RYC2019-026721-I to R.S.); European Research Council (Adv883739 to X.T., CoG-681434 to M.A.); Fundació la Marató de TV3 (project 201903-30-31-32 to X.T.); Deutsche Forschungsgemeinschaft (DFG GO3403/1-1 to T.G.); IBEC, IRB, and CIMNE are recipients of a Severo Ochoa Award of Excellence from the MINECO; European Commission (H2020-FETPROACT-01-2016-731957 to P.R-C.); La Caixa Foundation (LCF/PR/HR20/52400004 and ID 100010434 under the agreement LCF/ PR/HR20/52400004 to P.R-C. and X.T.). R.S. is a Serra Húnter fellow.The function of organs such as lungs, kidneys and mammary glands relies on the three-dimensional geometry of their epithelium. To adopt shapes such as spheres, tubes and ellipsoids, epithelia generate mechanical stresses that are generally unknown. Here we engineer curved epithelial monolayers of controlled size and shape and map their state of stress. We design pressurized epithelia with circular, rectangular and ellipsoidal footprints. We develop a computational method, called curved monolayer stress microscopy, to map the stress tensor in these epithelia. This method establishes a correspondence between epithelial shape and mechanical stress without assumptions of material properties. In epithelia with spherical geometry we show that stress weakly increases with areal strain in a size-independent manner. In epithelia with rectangular and ellipsoidal cross-section we find pronounced stress anisotropies that impact cell alignment. Our approach enables a systematic study of how geometry and stress influence epithelial fate and function in three-dimensions.Peer ReviewedPostprint (published version

    Seeded Growth Synthesis of Au-Fe3O4 Heterostructured Nanocrystals : Rational Design and Mechanistic Insights

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    Multifunctional hybrid nanoparticles comprising two or more entities with different functional properties are gaining ample significance in industry and research. Due to its combination of properties, a particularly appealing example is Au-FeO composite nanoparticles. Here we present an in-depth study of the synthesis of Au-FeO heterostructured nanocrystals (HNCs) by thermal decomposition of iron precursors in the presence of preformed 10 nm Au seeds. The role of diverse reaction parameters on the HNCs formation was investigated using two different precursors: iron pentacarbonyl (Fe(CO)) and iron acetylacetonate (Fe(acac)). The reaction conditions promoting the heterogeneous nucleation of FeO onto Au seeds were found to significantly differ depending on the precursor chosen, where Fe(acac) is considerably more sensitive to the variation of the parameters than Fe(CO) and more subject to homogeneous nucleation processes with the consequent formation of isolated iron oxide nanocrystals (NCs). The role of the surfactants was also crucial in the formation of well-defined and monodisperse HNCs by regulating the access to the Au surface. Similarly, the variations of the [Fe]/[Au] ratio, temperature, and employed solvent were found to act on the mean size and the morphology of the obtained products. Importantly, while the optical properties are rather sensitive to the final morphology, the magnetic ones are rather similar for the different types of obtained HNCs. The surface functionalization of dimer-like HNCs with silica allows their dispersion in aqueous media, opening the path to their use in biomedical applications

    Impact of introducing assisted electronic prescription on paediatric patient safety

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    [Resumen] Objetivo. El efecto de la implantación de la prescripción electrónica asistida en la seguridad de los pacientes pediátricos ha sido poco estudiado. El objetivo de este estudio es comparar los errores de medicación antes y después de su implantación en un hospital terciario. Material y métodos. Estudio cuasiexperimental comparativo de los errores de medicación detectados antes y después de la implantación de la prescripción electrónica. Se analizaron todas las líneas de tratamiento y se recogió el punto de la cadena donde ocurrió el error, el tipo de error y su causa. Se realizó un estudio Delphi sobre la importancia de cada error en el que participaron médicos, enfermeros y farmacéuticos. Resultados. Se incluyeron 166 pacientes (83 en cada etapa). Se detectó algún error en el 92% de los pacientes en la etapa preimplantacional (2,8 ± 2,1 errores/paciente) y en el 7,2% en la etapa postimplantacional (0,1 ± 0,4 errores/paciente). La prescripción electrónica asistida supuso una reducción absoluta del riesgo de error de un 40% (intervalo de confianza del 95% = 35,6-44,4%). Los lapsus/despistes fueron la principal causa de error en ambos grupos. En la etapa preimplantacional se consideraron graves el 9,5% de los errores, y en la etapa postimplantacional todos fueron leves o moderados. Conclusiones. La implantación de la prescripción electrónica con sistemas de ayuda a la prescripción, validación y administración de medicamentos reduce de forma significativa los errores de medicación y elimina los errores graves.[Abstract] Objective. There have been very few studies on the effect of assisted electronic prescription on paediatric patient safety. The objective of this study is to compare medication errors that occurred before and after its introduction in a tertiary hospital. Material and methods. A quasi-experimental comparative study of medication errors detected before and after assisted electronic prescription introduction. All treatment lines were analysed in order to detect the point in the chain where the medication error occurred, as well as its type and cause. A Delphi study was conducted on the importance of each medication error involving doctors, nurses, and pharmacists. Results. The study included 166 patients (83 at each stage). At least one medication error was detected in 92% in the pre-introduction phase patients (2.8 ± 2.1 errors/patient) and 7.2% of post-introduction phase patients (0.1 ± 0.4 errors/patient). The assisted electronic prescription led to an absolute risk reduction of 40% (95% confidence interval = 35.6-44.4%). The main cause of error was lapses and carelessness in both stages. Medication errors were considered serious in 9.5% of cases in the pre-introduction phase, while all of them were mild or moderate in the post-introduction phase. Conclusions. The assisted electronic prescription implementation with prescription, validation and medication administration assistance systems significantly reduces medication errors and eliminates serious errors

    Zinc blende and wurtzite CoO polymorph nanoparticles : rational synthesis and commensurate and incommensurate magnetic order

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    On the nanoscale, CoO can have different polymorph crystal structures, zinc blende and wurtzite, apart from rock salt, which is the stable one in bulk. However, the magnetic structures of the zinc blende and wurtzite phases remain virtually unexplored. Here we discuss some of the main parameters controlling the growth of the CoO wurtzite and zinc blende polymorphs by thermal decomposition of cobalt (II) acetylacetonate. In addition, we present a detailed neutron diffraction study of oxygen deficient CoO (CoO) nanoparticles with zinc blende (∼15 nm) and wurtzite (∼30 nm) crystal structures to unravel their magnetic order and its temperature evolution. The magnetic order of the zinc blende nanoparticles is antiferromagnetic and appears at the Néel temperature T ∼ 203 K. It corresponds to the 3rd type of magnetic ordering in a face-centered cubic lattice with magnetic moments aligned along a cube edge. The magnetic structure in the wurtzite nanoparticles turned out to be rather complex with two perpendicular components. One component is incommensurate, of the longitudinal spin wave type, with the magnetic moments confined in the ab-plane. In the perpendicular direction, this magnetic order is uncorrelated, forming quasi-two-dimensional magnetic layers. The component of the magnetic moment, aligned along the hexagonal axis, is commensurate and corresponds to the antiferromagnetic order known as the 2nd type in a wurtzite structure. The Néel temperature of wurtzite phase is estimated to be ∼109 K. The temperature dependence of the magnetic reflections confirms the reduced dimensionality of the incommensurate magnetic order. Incommensurate magnetic structures in nanoparticles are an unusual phenomenon and in the case of wurtzite CoO it is probably caused by structural defects (e.g., vacancies, strains and stacking faults)

    Inflammatory cytokines and organ dysfunction associate with the aberrant DNA methylome of monocytes in sepsis

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    Background: Sepsis, a life-threatening organ dysfunction caused by a dysregulated systemic immune response to infection, associates with reduced responsiveness to subsequent infections. How such tolerance is acquired is not well understood but is known to involve epigenetic and transcriptional dysregulation. Methods: Bead arrays were used to compare global DNA methylation changes in patients with sepsis, noninfectious systemic inflammatory response syndrome, and healthy controls. Bioinformatic analyses were performed to dissect functional reprogramming and signaling pathways related to the acquisition of these specific DNA methylation alterations. Finally, in vitro experiments using human monocytes were performed to test the induction of similar DNA methylation reprogramming. Results: Here, we focused on DNA methylation changes associated with sepsis, given their potential role in stabilizing altered phenotypes. Tolerized monocytes from patients with sepsis display changes in their DNA methylomes with respect to those from healthy controls, affecting critical monocyte-related genes. DNA methylation profiles correlate with IL-10 and IL-6 levels, significantly increased in monocytes in sepsis, as well as with the Sequential Organ Failure Assessment score; the observed changes associate with TFs and pathways downstream to toll-like receptors and inflammatory cytokines. In fact, in vitro stimulation of toll-like receptors in monocytes results in similar gains and losses of methylation together with the acquisition of tolerance. Conclusion: We have identified a DNA methylation signature associated with sepsis that is downstream to the response of monocytes to inflammatory signals associated with the acquisition of a tolerized phenotype and organic dysfunction
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