109 research outputs found
Asymmetric Organocatalysts Supported on Vinyl Addition Polynorbornenes for Work in Aqueous Media
Producción CientíficaIn an effort to identify novel polymer architectures suitable for the covalent supporting of catalysts, L–proline derivatives have been immobilized onto rationally designed vinyl addition polynorbornene (VA-PNB) resins through copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions. The fully saturated VA-PNB resins have been found to be optimal catalyst supports, the resulting proline-functionalized resins behaving as very active, easily recoverable and highly reusable organocatalysts for the asymmetric direct aldol reaction of benzaldehydes with ketones in aqueous media. The obtained results show that the combination of modular,
VA-PNB resins with proline derivatives through triazole linkers represent a promising strategy for the immobilization of organocatalytic species.Ministerio de Economía, Industria y Competitividad (CTQ2013-48406-P)Ministerio de Economía, Industria y Competitividad (CTQ2012-38594-C02-01)Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA373A11-2)Generalitat de Catalunya (Grant 2014SGR827
The IFMIF-EVEDA accelerator beam dump design
The IFMIF-EVEDA accelerator will be a 9 MeV, 125 mA cw deuteron accelerator prototype for verifying the validity of the 40 MeV accelerator design for IFMIF. A beam dump designed for maximum power of 1.12 MW will be used to stop the beam at the accelerator exit. The conceptual design for the IFMIF-EVEDA accelerator beam dump is based on a conical beam stop made of OFE copper. The cooling system uses an axial high velocity flow of water pressurized up to 3.4 × 105 Pa to avoid boiling. The design has been shown to be compliant with ASME mechanical design rules under nominal full power conditions. A sensitivity analysis has been performed to take into account the possible margin on the beam properties at the beam dump entrance. This analysis together with the study of the maintenance issues and the mounting and dismounting operations has led to the complete design definition
Automatic quantitative MRI texture analysis in small-for-gestational-age fetuses discriminates abnormal neonatal neurobehavior
Background: We tested the hypothesis whether texture analysis (TA) from MR images could identify patterns associated with an abnormal neurobehavior in small for gestational age (SGA) neonates. Methods: Ultrasound and MRI were performed on 91 SGA fetuses at 37 weeks of GA. Frontal lobe, basal ganglia, mesencephalon and cerebellum were delineated from fetal MRIs. SGA neonates underwent NBAS test and were classified as abnormal if $1 area was ,5th centile and as normal if all areas were .5th centile. Textural features associated with neurodevelopment were selected and machine learning was used to model a predictive algorithm. Results: Of the 91 SGA neonates, 49 were classified as normal and 42 as abnormal. The accuracies to predict an abnormal neurobehavior based on TA were 95.12% for frontal lobe, 95.56% for basal ganglia, 93.18% for mesencephalon and 83.33% for cerebellum. Conclusions: Fetal brain MRI textural patterns were associate
Raman-Mössbauer-XRD studies of selected samples from “Los Azulejos” outcrop: A possible analogue for assessing the alteration processes on Mars
The outcrop of “Los Azulejos” is visible at the interior of the Cañadas Caldera in Tenerife Island (Spain). It exhibits a great variety of alteration processes that could be considered as terrestrial analogue for several geological processes on Mars. This outcrop is particularly interesting due to the content of clays, zeolite, iron oxides, and sulfates corresponding to a hydrothermal alteration catalogued as “Azulejos” type alteration. A detailed analysis by portable and laboratory Raman systems as well as other different techniques such as X ray diffraction (XRD) and Mössbauer spectroscopy has been carried out (using twin-instruments from Martian lander missions: Mössbauer spectrometer MIMOS-II from the NASA-MER mission of 2001 and the XRD diffractometer from the NASA-MSL Curiosity mission of 2012). The mineral identification presents the following mineral species: magnetite, goethite, hematite, anatase, rutile, quartz, gregoryite, sulphate (thenardite and hexahydrite), diopside, feldspar, analcime, kaolinite and muscovite. Moreover, the in-situ Raman and Micro-Raman measurements have been performed in order to compare the capabilities of the portable system specially focused for the next ESA Exo-Mars mission. The mineral detection confirms the sub-aerial alteration on the surface and the hydrothermal processes by the volcanic fluid circulations in the fresh part. Therefore, the secondary more abundant mineralization acts as the color agent of the rocks. Thus, the zeolite-illite group is the responsible for the bluish coloration, as well as the feldspars and carbonates for the whitish and the iron oxide for the redish parts. The XRD system was capable to detect a minor proportion of pyroxene, which is not visible by Raman and Mössbauer spectroscopy due to the “Azulejos” alteration of the parent material on the outcrop. On the other hand, Mössbauer spectroscopy was capable of detecting different types of iron-oxides (Fe3+/2+-oxide phases). These analyses emphasize the strength of the different techniques and the working synergy of the three different techniques together for planetary space missions.The work was supported by the MICINN with the Project AYA-2008-04529.Peer reviewe
Interleukin 18 maintains a long-standing inflammation in coeliac disease patients
Producción CientíficaDietary gluten induces an early response in the intestine of coeliac disease
patients (CD), within a few hours, and this is driven by high levels of proinflammatory
cytokines, including IFNg and IL-15, as has been thoroughly
shown by gluten stimulation of biopsy explants. Our aim was to identify the
immune mediators involved in the long-standing inflammation in untreated
CD patients at diagnosis. mRNA and protein levels of TNFa, IL-12(p35),
IL-12(p40), IL-15, IL-18 and IL-23(p19) were quantified in biopsies from
active CD patients, CD patients on a gluten-free diet (GFD), healthy controls,
and patients with non-CD inflammation and mild histological changes in the
intestine. Biopsies from CD patients on a GFD were also stimulated in vitro
with gliadin, and protein expression of IL-15 and IL-18 was analysed. Levels of
IL-12 and IL-23 mRNA are nearly absent, and TNFa levels remain unchanged
among different groups. Both the active and inactive forms of IL-18 protein
have been found in all samples from active CD, and protein expression was
only localized within the crypts. Levels of IL-15 mRNA remain unchanged,
and protein expression, localized within the lamina propria, is found in a
small number of samples. In vitro stimulation with gluten induces the expression
of IL-15 and IL-18. In active CD, the early response following gluten
intake characterized by high IFNg levels is driven by IL-18, and probably
IL-15, and this alternates with periods of long-standing inflammation with
moderate IFNg levels, maintained by IL-18 alone
Machine learning methods applied to combined Raman and LIBS spectra: Implications for mineral discrimination in planetary missions
Producción CientíficaThe combined analysis of geological targets by complementary spectroscopic techniques could enhance the characterization of the mineral phases found on Mars. This is indeed the case with the SuperCam instrument onboard the Perseverance rover. In this framework, the present study seeks to evaluate and compare multiple machine learning techniques for the characterization of carbonate minerals based on Raman-LIBS (Laser-Induced Breakdown Spectroscopy) spectroscopic data. To do so, a Ca-Mg prediction curve was created by mixing hydromagnesite and calcite at different concentration ratios. After their characterization by Raman and LIBS spectroscopy, different multivariable machine learning (Gaussian process regression, support vector machines, ensembles of trees, and artificial neural networks) were used to predict the concentration ratio of each sample from their respective datasets. The results obtained by separately analyzing Raman and LIBS data were then compared to those obtained by combining them. By comparing their performance, this work demonstrates that mineral discrimination based on Gaussian and ensemble methods optimized the combine of Raman-LIBS dataset outperformed those ensured by Raman and LIBS data alone. This demonstrated that the fusion of data combination and machine learning is a promising approach to optimize the analysis of spectroscopic data returned from Mars.Agencia Estatal de Investigación, grant (PID2022-142490OB-C32)Ministerio de Economía y Competitividad (MINECO),Grant/Award Number (RDE2018-102600-T
A Predictive Model and Risk Factors for Case Fatality of COVID-19
This study aimed to create an individualized analysis model of the risk of intensive care unit (ICU) admission or death for coronavirus disease 2019 (COVID-19) patients as a tool for the rapid clinical management of hospitalized patients in order to achieve a resilience of medical resources. This is an observational, analytical, retrospective cohort study with longitudinal follow-up. Data were collected from the medical records of 3489 patients diagnosed with COVID-19 using RT-qPCR in the period of highest community transmission recorded in Europe to date: February-June 2020. The study was carried out in in two health areas of hospital care in the Madrid region: the central area of the Madrid capital (Hospitales de Madrid del Grupo HM Hospitales (CH-HM), n = 1931) and the metropolitan area of Madrid (Hospital Universitario Príncipe de Asturias (MH-HUPA) n = 1558). By using a regression model, we observed how the different patient variables had unequal importance. Among all the analyzed variables, basal oxygen saturation was found to have the highest relative importance with a value of 20.3%, followed by age (17.7%), lymphocyte/leukocyte ratio (14.4%), CRP value (12.5%), comorbidities (12.5%), and leukocyte count (8.9%). Three levels of risk of ICU/death were established: low-risk level (20%). At the high-risk level, 13% needed ICU admission, 29% died, and 37% had an ICU-death outcome. This predictive model allowed us to individualize the risk for worse outcome for hospitalized patients affected by COVID-19
De novo erythroleukemia chromosome features include multiple rearrangements, with special involvement of chromosomes 11 and 19
Erythroid leukemia (ERL or AML-M6) is an uncommon subtype of acute myeloid leukemia, the clinical, morphological, and genetic behavior of which needs further characterization. We analyzed a homogeneous group of 23 de novo AML-M6 patients whose bone marrow cells showed complex karyotypes. We also analyzed eight leukemia cell lines with erythroid phenotype, performing detailed molecular cytogenetic analyses, including spectral karyotyping (SKY) in all samples. The main features are: (1) A majority of patients (56%) had hypodiploidy. Loss of genetic material was the most common genetic change, especially monosomies of chromosome 7 or 18, and deletions of chromosome arm 5q. Taken together, 87% of the cases displayed aberrations involving chromosome 5 or 8. (2) We describe a novel, cryptic, and recurrent translocation, t(11;19)(p11.2;q13.1). Another translocation, t(12;21)(p11.2;q11.2), was found to be recurrent in a patient with ERL and in the K562 cell line. (3) MLL gene rearrangements were detected in 20% of cases (three translocations and three amplifications) and, overall, we defined 52 rearrangements (excluding deletions) with a mean of 2.3 translocations per patient. (4) Of the structural aberrations, 21% involved chromosomes 11 and 19. Most of the rearrangements were unbalanced; only 13 reciprocal translocations were observed. The general picture of chromosomal aberrations in cell lines did not reflect what occurred in patient samples. However, both primary samples and cell lines shared three common breakpoints at 19q13.1, 20q11.2, and 21q11.2. This is the first molecular cytogenetic description of the karyotype abnormalities present in patients with ERL. It should assist in the identification of genes involved in erythroleukemogenesis
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