121 research outputs found
NO2 climatology in the northern subtropical region: diurnal, seasonal and interannual variability
Daily NO2 vertical column density (VCD) has been routinely measured by zenith sky spectroscopy at the subtropical station of Izaña (28° N, 16° W) since 1993 in the framework of the Network for the Detection of Atmospheric Composition Change (NDACC). Based on 14 years of data the first low latitude NO2 VCD climatology has been established and the main characteristics from short timescales of one day to interannual variability are presented. Instrumental descriptions and different sources of errors are described in detail. The observed diurnal cycle follows that expected by gas-phase NOx chemistry, as can be shown by the good agreement with a vertically integrated chemical box model, and is modulated by solar radiation. The seasonal evolution departs from the phase of the hours of daylight, indicating the signature of upper stratospheric temperature changes. From the data record (1993–2006) no significant long-term trends in NO2 VCD can be inferred. Comparison of the ground-based data sets with nadir-viewing satellite spectrometers shows excellent agreement for SCIAMACHY with differences between both datasets of 1.1%. GOME displays unrealistic features with the largest discrepancies during summer. The ground-based data are compared with long-term output of the SLIMCAT 3-D chemical transport model (CTM). The basic model, forced by ECMWF (ERA-40) analyses, captures the observed NO2 annual cycle but significantly underestimates the spring/summer maximum (by 12% at sunset and up to 25% at sunrise). In a model run which uses assimilation of satellite CH4 profiles to constrain the model long-lived tracers the agreement is significantly improved. This improvement in modelled column NO2 is due to better modelled NOy profiles and points to transport errors in the ECMWF ERA-40 reanalyses.Routine measurements have been possible thanks to the funding provided by the projects QUILT (EU EVK2-CT2000-0059) SCOUT-O3 (EU 505390-GOCE-CT-2004), TROMPETA (MCyT CGL2004-03669) and is on-going through GEOMON (EU FP6-2005-Global-4- 036677)
Differences between 1999 and 2010 across the Falkland Plateau: fronts and water masses
Decadal differences in the Falkland Plateau are
studied from the two full-depth hydrographic data collected
during the ALBATROSS (April 1999) and MOC-Austral
(February 2010) cruises. Differences in the upper 100 dbar
are due to changes in the seasonal thermocline, as the ALBATROSS
cruise took place in the austral fall and the MOCAustral
cruise in summer. The intermediate water masses
seem to be very sensitive to the wind conditions existing in
their formation area, showing cooling and freshening for the
decade as a consequence of a higher Antarctic Intermediate
Water (AAIW) contribution and of a decrease in the Subantarctic
Mode Water (SAMW) stratum. The deeper layers
do not exhibit any significant change in the water mass properties.
The Subantarctic Front (SAF) in 1999 is observed at
52.2–54.8 W with a relative mass transport of 32.6 Sv. In
contrast, the SAF gets wider in 2010, stretching from 51.1
to 57.2 W (the Falkland Islands), and weakening to 17.9 Sv.
Changes in the SAF can be linked with the westerly winds
and mainly affect the northward flow of Subantarctic Surface
Water (SASW), SAMW and AAIW/Antarctic Surface Water
(AASW). The Polar Front (PF) carries 24.9 Sv in 1999
(49.8–44.4 W), while in 2010 (49.9–49.2 W) it narrows
and strengthens to 37.3 Sv.En prens
COVID-19 and inflammatory bowel disease: questions arising from patient care and follow-up during the initial phase of the pandemic (February-April 2020)
COVID-19 is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was described in China in late 2019. There are currently more than three million diagnosed cases, constituting a pandemic which has caused a worldwide crisis. The devastating effects of this infection are due to its highly contagious nature and although mild forms predominate, in absolute values, the rates for severe forms and mortality are very high. The information on the characteristics of the infection in inflammatory bowel disease is of special interest, as these patients have higher attendance at health centres, which may increase their risk of infection. Furthermore, the treatments used to control the inflammatory activity may modify the disease course of COVID-19. The Spanish Working Group on Crohn's Disease and Ulcerative Colitis and the Spanish Nurses Working Group on Inflammatory Bowel Disease have prepared this document as a practical response to some common questions about the treatment of these patients
Adipose tissue knockdown of lysozyme reduces local inflammation and improves adipogenesis in high-fat diet-fed mice
Chronic systemic low-level inflammation in metabolic disease is known to affect adipose tissue biology. Lysozyme (LYZ) is a major innate immune protein but its role in adipose tissue has not been investigated. Here, we aimed to investigate LYZ in human and rodents fat depots, and its possible role in obesity-associated adipose tissue dysfunction. LYZ mRNA and protein were identified to be highly expressed in adipose tissue from subjects with obesity and linked to systemic chronic-low grade inflammation, adipose tissue inflammation and metabolic disturbances, including hyperglycemia, dyslipidemia and decreased markers of adipose tissue adipogenesis. These findings were confirmed in experimental models after a high-fat diet in mice and rats and also in ob/ob mice. Importantly, specific inguinal and perigonadal white adipose tissue lysozyme (Lyz2) gene knockdown in high-fat diet-fed mice resulted in improved adipose tissue inflammation in parallel to reduced lysozyme activity. Of note, Lyz2 gene knockdown restored adipogenesis and reduced weight gain in this model. In conclusion, altogether these observations point to lysozyme as a new actor in obesity-associated adipose tissue dysfunction. The therapeutic targeting of lysozyme production might contribute to improve adipose tissue metabolic homeostasis
Evolutionary and phenotypic characterization of two spike mutations in European lineage 20E of SARS-CoV-2.
We have detected two mutations in the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at amino acid positions 1163 and 1167 that appeared independently in multiple transmission clusters and different genetic backgrounds. Furthermore, both mutations appeared together in a cluster of 1,627 sequences belonging to clade 20E. This cluster is characterized by 12 additional single nucleotide polymorphisms but no deletions. The available structural information on the S protein in the pre- and postfusion conformations predicts that both mutations confer rigidity, which could potentially decrease viral fitness. Accordingly, we observed reduced infectivity of this spike genotype relative to the ancestral 20E sequence in vitro, and the levels of viral RNA in nasopharyngeal swabs were not significantly higher. Furthermore, the mutations did not impact thermal stability or antibody neutrali- zation by sera from vaccinated individuals but moderately reduce neutralization by convalescent-phase sera from the early stages of the pandemic. Despite multi- ple successful appearances of the two spike mutations during the first year of SARS-CoV-2 evolution, the genotype with both mutations was displaced upon the expansion of the 20I (Alpha) variant. The midterm fate of the genotype investi- gated was consistent with the lack of advantage observed in the clinical and ex- perimental data
Dossier executiu del prototip construït a la finca de C. Carretes, 1
Dossier executiu del prototip construït a la finca de C. Peu de la Creu, 32 en l'àmbit del projecte CO-HAB-RAVALPreprin
Search for CP Violation in the Decay Z -> b (b bar) g
About three million hadronic decays of the Z collected by ALEPH in the years
1991-1994 are used to search for anomalous CP violation beyond the Standard
Model in the decay Z -> b \bar{b} g. The study is performed by analyzing
angular correlations between the two quarks and the gluon in three-jet events
and by measuring the differential two-jet rate. No signal of CP violation is
found. For the combinations of anomalous CP violating couplings, and , limits of \hat{h}_b < 0.59h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st
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