Effect of an organotin catalyst on the physicochemical properties and biocompatibility of castor oil-based polyurethane/cellulose composites

[EN] Polyurethane/cellulose composites were synthesized from castor-oil-derived polyols and isophorone diisocyanate using dibutyltin dilaurate (DBTDL) as the catalyst. Materials were obtained by adding 2% cellulose in the form of either microcrystals (20 lm) or nanocrystals obtained by acid hydrolysis. The aim was to assess the effects of filler particle size and the use of a catalyst on the physicochemical properties and biological response of these composites. The addition of the catalyst was found to be essential to prevent filler aggregations and to enhance the tensile strength and elongation at break. The cellulose particle size influenced the composite properties, as its nanocrystals heighten hydrogen bond interactions between the filler surface and polyurethane domains, improving resistance to hydrolytic degradation. All hybrids retained cell viability, and the addition of DBTDL did not impair their biocompatibility. The samples were prone to calcification, which suggests that they could find application in the development of bioactive materials.Universidad de La Sabana supported this work under Grant No. ING-176-2016. S.V.V. acknowledges the Universidad de La Sabana for the Teaching Assistant Scholarship for his master's studies. J.A.G.T. and A.V.L. acknowledge the support of the Spanish Ministry of Economy and Competitiveness (MINECO) through project DPI2015-65401-C3-2-R (including FEDER financial support). The authors acknowledge the assistance and advice of the Electron Microscopy Service of the UPV. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program. CIBER Actions are financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Villegas-Villalobos, S.; Diaz, L.; Vilariño, G.; Vallés Lluch, A.; Gómez-Tejedor, J.; Valero, M. (2018). 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Paediatric Barcelona Olfactory Test-6 (pBOT-6): Validation of a Combined Odour Identification and Threshold Screening Test in Healthy Spanish Children and Adolescents

Background: Few odour tests have been created for children. Objectives: The aim of the present study was to develop and validate a simple and quick olfactory test, suitable for the evaluation of odour identification and threshold in a Spanish paediatric population, the paediatric Barcelona Olfactory Test-6 (pBOT-6).The pBOT-6 consisted in a set of 6 odorants for a forced-choice identification test (IT), and a 6 dilutions phenyl ethyl alcohol geometric series for the threshold test (TT). The pBOT-6 was compared with the U-sniff test (a validated international paediatric smell test) in 131 Spanish healthy volunteers aged 6-17 years. A Bland-Altman plot was used to determine the agreement between two tests. Reliability was analyzed in fifteenvolunteers using the intraclass correlation coefficient (ICC). Normative data was obtained and 8 children diagnosed with subjective smell loss were tested for validation.Bland-Altman analysis demonstrated a minimal bias of -1.71% with upper and lower limit of agreement of -31.1% and 27.6%, respectively. The ICC was 0.83 (95% CI 0.6-0.96) for the IT and 0.73 (95% CI 0.36-0.9) for the TT, showing excellent and good consistency between measurements over time. Mean pBOT-6 scores were significantly higher in healthy volunteers compared with patients with smell loss. Discrimination between normosmia and smell loss was achieved with a sensitivity of 96.9% and a specificity of 100%.The pBOT-6 offers an effectiveand fast method useful in clinical routine to distinguish, with high sensitivity and specificity, between paediatric patients with normosmia and those with smell dysfunction

Disociación espino-pélvica : a propósito de un caso

Spinopelvic dissociation is a relatively unknown injury, probably underdiagnosed. The term is applied to those fractures of the sacrum which combines a transverse fracture with sagittal fracture in both sacral wings, resulting in a mechanical separation between the spine and the pelvis. It?s really important to be alert in a high energy multiple trauma. The treatment of choice, except exceptions, is surgery. About associated complications, we must detect preoperative neurological injury of these patients due to it will be the main determinant of the long-term prognosis. The objective of this review it is to introduce this rare pathology with important implications through a clinical case

Volcanism and climate change as drivers in Holocene depositional dynamic of Laguna del Maule (Andes of central Chile – 36° S)

Late Quaternary volcanic basins are active landscapes from which detailed archives of past climate and seismic and volcanic activity can be obtained. A multidisciplinary study performed on a transect of sediment cores was used to reconstruct the depositional evolution of the high-elevation Laguna del Maule (LdM) (36∘ S, 2180 m a.s.l., Chilean Andes). The recovered 5 m composite sediment sequence includes two thick turbidite units (LT1 and LT2) and numerous tephra layers (23 ash and 6 lapilli). We produced an age model based on nine new 14C AMS dates, existing 210Pb and 137Cs data, and the Quizapú ash horizon (1932 CE). According to this age model, the relatively drier Early Holocene was followed by a phase of increased productivity during the mid-Holocene and higher lake levels after 4.0 ka cal BP. Major hydroclimate transitions occurred at ca. 11, 8.0, 4.0 and 0.5 ka cal BP. Decreased summer insolation and winter precipitation due to a southward shift in the southern westerly winds and a strengthened Pacific Subtropical High could explain Early Holocene lower lake levels. Increased biological productivity during the mid-Holocene (∼8.0 to 6.0 ka cal BP) is coeval with a warm–dry phase described for much of southern South America. Periods of higher lake productivity are synchronous to a higher frequency of volcanic events. During the Late Holocene, the tephra layers show compositional changes suggesting a transition from silica-rich to silica-poor magmas at around 4.0 ka cal BP. This transition was synchronous with increased variability of sedimentary facies and geochemical proxies, indicating higher lake levels and increased moisture at LdM after 4.0 ka cal BP, most likely caused by the inception of current El Niño–Southern Oscillation and Pacific Decadal Oscillation (ENSO–PDO) dynamics in central Chile.Postprin

Centennial-scale precipitation anomalies in the southern Altiplano (18° S) suggest an extra-tropical driver for the South American Summer Monsoon during the late Holocene

Modern precipitation anomalies in the Altiplano region of South America are closely linked to the strength of the South American Summer Monsoon (SASM) which is influenced by large-scales climate features sourced in the tropics such as latitudinal shifts of the Intertropical Convergence Zone (ITCZ) and El Niño-Southern Oscillation (ENSO). However, the timing, direction and spatial extent of precipitation changes prior to the instrumental period are still largely unknown, preventing a better understanding of the long-term drivers of the SASM and their effects over the Altiplano. Here we present a detailed pollen reconstruction from a sedimentary sequence covering the period between 4500-1000 cal yr BP in Lago Chungará (18° S; 4570 masl), a high elevation lake in the southwestern margin of the Altiplano where precipitation is delivered almost exclusively during the mature phase of the SASM in the austral summer. We distinguish three well-defined centennial-scale anomalies, with dry conditions between 4100-3300 and 1600-1000 cal yr BP, and a conspicuous humid interval between 2400-1600 cal yr BP; which resulted from weakening and strengthening of the SASM respectively. Comparisons with other climate reconstructions from the Altiplano, the Atacama Desert, the Tropical Andes and the southwestern Atlantic coast reveal that - unlike the modern climatological controls - past precipitation anomalies at Lago Chungará were largely decoupled from north-south shifts in the ITCZ and ENSO. A regionally coherent pattern of centennial-scale SASM variations and a significant latitudinal gradient in precipitation responses suggest the contribution of an extra-tropical moisture source for the SASM, with significant effects over precipitation variability in the Southern Altiplano

Updating the Food-Based Dietary Guidelines for the Spanish Population: The Spanish Society of Community Nutrition (SENC) Proposal

Diet-related risk factors and physical inactivity are among the leading risk factors for disability and are responsible for a large proportion of the burden of chronic non-communicable diseases. Food-based dietary guidelines (FBDGs) are useful tools for nutrition policies and public health strategies to promote healthier eating and physical activity. In this paper, we discuss the process followed in developing the dietary guidelines for the Spanish population by the Spanish Society of Community Nutrition (SENC) and further explain the collaboration with primary healthcare practitioners as presented in the context of the NUTRIMAD 2018 international congress of SENC. From a health in all policies approach, SENC convened a group of experts in nutrition and public health to review the evidence on diet-health, nutrient intake and food consumption in the Spanish population, as well as food preparation, determinants and impact of diet on environmental sustainability. The collaborative group drafted the document and designed the graphic icon, which was then subject to a consultation process, discussion, and qualitative evaluation. Next, a collaborative group was established to plan a dissemination strategy, involving delegates from all the primary healthcare scientific societies in Spain. A product of this collaboration was the release of an attractive, easy-to-understand publication

DNA multigene characterization of Fasciola hepatica and Lymnaea neotropica and its fascioliasis transmission capacity in Uruguay, with historical correlation, human report review and infection risk analysis

Fascioliasis is a highly pathogenic zoonotic disease emerging in recent decades, in part due to the effects of climate and global changes. South America is the continent presenting more numerous human fascioliasis endemic areas and the highest Fasciola hepatica infection prevalences and intensities known in humans. These serious public health scenarios appear mainly linked to altitude areas in Andean countries, whereas lowland areas of non-Andean countries, such as Uruguay, only show sporadic human cases or outbreaks. To understand this difference, we characterized F. hepatica from cattle and horses and lymnaeids of Uruguay by sequencing of ribosomal DNA ITS-2 and ITS-1 spacers and mitochondrial DNA cox1, nad1 and 16S genes. Results indicate that vectors belong to Lymnaea neotropica instead of to Lymnaea viator, as always reported from Uruguay. Our correlation of fasciolid and lymnaeid haplotypes with historical data on the introduction and spread of livestock species into Uruguay allow to understand the molecular diversity detected. We study the life cycle and transmission features of F. hepatica by L. neotropica of Uruguay under standardized experimental conditions to enable a comparison with the transmission capacity of F. hepatica by Galba truncatula at very high altitude in Bolivia. Results demonstrate that although L. neotropica is a highly efficient vector in the lowlands, its transmission capacity is markedly lower than that of G. truncatula in the highlands. On this baseline, we review the human fascioliasis cases reported in Uruguay and analyze the present and future risk of human infection in front of future climate change estimations

Search for heavy particles decaying into a top-quark pair in the fully hadronic final state in pp collisions at s =13 TeV with the ATLAS detector

A search for new particles decaying into a pair of top quarks is performed using proton-proton collision data recorded with the ATLAS detector at the Large Hadron Collider at a center-of-mass energy of s=13 TeV corresponding to an integrated luminosity of 36.1 fb-1. Events consistent with top-quark pair production and the fully hadronic decay mode of the top quarks are selected by requiring multiple high transverse momentum jets including those containing b-hadrons. Two analysis techniques, exploiting dedicated top-quark pair reconstruction in different kinematic regimes, are used to optimize the search sensitivity to new hypothetical particles over a wide mass range. The invariant mass distribution of the two reconstructed top-quark candidates is examined for resonant production of new particles with various spins and decay widths. No significant deviation from the Standard Model prediction is observed and limits are set on the production cross-section times branching fraction for new hypothetical Z′ bosons, dark-matter mediators, Kaluza-Klein gravitons and Kaluza-Klein gluons. By comparing with the predicted production cross sections, the Z′ boson in the topcolor-assisted-technicolor model is excluded for masses up to 3.1-3.6 TeV, the dark-matter mediators in a simplified framework are excluded in the mass ranges from 0.8 to 0.9 TeV and from 2.0 to 2.2 TeV, and the Kaluza-Klein gluon is excluded for masses up to 3.4 TeV, depending on the decay widths of the particles.Peer Reviewe

Search for tt¯ resonances in fully hadronic final states in pp collisions at √s = 13 TeV with the ATLAS detector

This paper presents a search for new heavy particles decaying into a pair of top quarks using 139 fb of proton-proton collision data recorded at a centre-of-mass energy of s = 13 TeV with the ATLAS detector at the Large Hadron Collider. The search is performed using events consistent with pair production of high-transverse-momentum top quarks and their subsequent decays into the fully hadronic final states. The analysis is optimized for resonances decaying into a tt¯ pair with mass above 1.4 TeV, exploiting a dedicated multivariate technique with jet substructure to identify hadronically decaying top quarks using large-radius jets and evaluating the background expectation from data. No significant deviation from the background prediction is observed. Limits are set on the production cross-section times branching fraction for the new Z′ boson in a topcolor-assisted-technicolor model. The Z′ boson masses below 3.9 and 4.7 TeV are excluded at 95% confidence level for the decay widths of 1% and 3%, respectively. [Figure not available: see fulltext.