Atmospheric methane variability: Centennial-scale signals in the Last Glacial Period

In order to understand atmospheric methane (CH$_{4}$) biogeochemistry now and in the future, we must apprehend its natural variability, without anthropogenic influence. Samples of ancient air trapped within ice cores provide the means to do this. Here we analyze the ultrahigh-resolution CH$_{4}$ record of the West Antarctic Ice Sheet Divide ice core 67.2–9.8 ka and find novel, atmospheric CH$_{4}$ variability at centennial time scales throughout the record. This signal is characterized by recurrence intervals within a broad 80–500 year range, but we find that age-scale uncertainties complicate the possible isolation of any periodic frequency. Lower signal amplitudes in the Last Glacial relative to the Holocene may be related to incongruent effects of firn-based signal smoothing processes. Within interstadial and stadial periods, the peak-to-peak signal amplitudes vary in proportion to the underlying millennial-scale oscillations in CH$_{4}$ concentration—the relative amplitude change is constant. We propose that the centennial CH$_{4}$ signal is related to tropical climate variability that influences predominantly low-latitude wetland CH$_{4}$ emissions.This study was funded by the U.S. National Science Foundation (NSF) grants 0944552, 1142041, and 0968391 to E.J.B. and 0839093 and 1142166 to J.R.M. A European Union Horizon 2020 Marie Curie Individual Fellowship (grant 58120, SEADOG) provided partial support for R.H.R. This work also benefitted from funding to X.F. from the French RPD COCLICO ANR program (ANR-10-RPDOC-002-01), the INSU/LEFE project IceChrono, and the Ars Cuttoli foundation and additionally from the UK Natural Environment Research Council (NERC) grant NE/P009271/1 awarded to L.C.S. Grateful thanks to B. Tournadre for help in Fletcher Promontory ice core analysis. The authors appreciate the support of the WAIS Divide Science Coordination Office at the Desert Research Institute, Reno, NV, USA, and University of New Hampshire, USA, for the collection and distribution of the WD ice core (NSF grants 0230396, 0440817, 0944348, and 0944266). We are grateful to all participants in the field effort led by K. Taylor. The NSF Office of Polar Programs also funded the Ice Drilling Program Office and Ice Drilling Design and Operations group, the National Ice Core Laboratory, Raytheon Polar Services, and the 109th New York Air National Guard

Atmospheric methane variability: Centennial-scale signals in the Last Glacial Period

In order to understand atmospheric methane (CH$_{4}$) biogeochemistry now and in the future, we must apprehend its natural variability, without anthropogenic influence. Samples of ancient air trapped within ice cores provide the means to do this. Here we analyze the ultrahigh-resolution CH$_{4}$ record of the West Antarctic Ice Sheet Divide ice core 67.2–9.8 ka and find novel, atmospheric CH$_{4}$ variability at centennial time scales throughout the record. This signal is characterized by recurrence intervals within a broad 80–500 year range, but we find that age-scale uncertainties complicate the possible isolation of any periodic frequency. Lower signal amplitudes in the Last Glacial relative to the Holocene may be related to incongruent effects of firn-based signal smoothing processes. Within interstadial and stadial periods, the peak-to-peak signal amplitudes vary in proportion to the underlying millennial-scale oscillations in CH$_{4}$ concentration—the relative amplitude change is constant. We propose that the centennial CH$_{4}$ signal is related to tropical climate variability that influences predominantly low-latitude wetland CH$_{4}$ emissions.This study was funded by the U.S. National Science Foundation (NSF) grants 0944552, 1142041, and 0968391 to E.J.B. and 0839093 and 1142166 to J.R.M. A European Union Horizon 2020 Marie Curie Individual Fellowship (grant 58120, SEADOG) provided partial support for R.H.R. This work also benefitted from funding to X.F. from the French RPD COCLICO ANR program (ANR-10-RPDOC-002-01), the INSU/LEFE project IceChrono, and the Ars Cuttoli foundation and additionally from the UK Natural Environment Research Council (NERC) grant NE/P009271/1 awarded to L.C.S. Grateful thanks to B. Tournadre for help in Fletcher Promontory ice core analysis. The authors appreciate the support of the WAIS Divide Science Coordination Office at the Desert Research Institute, Reno, NV, USA, and University of New Hampshire, USA, for the collection and distribution of the WD ice core (NSF grants 0230396, 0440817, 0944348, and 0944266). We are grateful to all participants in the field effort led by K. Taylor. The NSF Office of Polar Programs also funded the Ice Drilling Program Office and Ice Drilling Design and Operations group, the National Ice Core Laboratory, Raytheon Polar Services, and the 109th New York Air National Guard

Acute epiglottitis as the initial presentation of pediatric Systemic Lupus Erythematosus

We report a case of a 5-year old girl, who initially presented with acute epiglottitis, sepsis and multi-organ failure. She was subsequently diagnosed as having Systemic Lupus Erythematosus. To the best of our knowledge, this article describes the first case of Haemophilus influenzae type f epiglottitis as the initial presentation of SLE in childhood

Pediatricians and nutritionists knowledge about treatment of cow milk allergy in infants

OBJECTIVE: Evaluate the knowledge of pediatricians and nutritionists regarding the exclusion diet of cow milk and derivates, with emphasis on questions related to the nutrition of children submitted to such diet. METHODS: Cross-sectional study that enrolled pediatricians (n=53) and nutritionists (n=29) from public hospitals in São Paulo, Brazil, during 2005. Data was collected through self-administered questionnaires. RESULTS: The age of the professionals varied from 21 to 50 years old. Regarding professional experience, 41.2% were graduated for less than five years and 91.6% had a specialization course, masters and/or PhD degree. The vast majority of professionals (97.5%) confirmed that they regularly evaluated the diet of children that needed exclusion of cow milk. However, only 48% of the professionals conducted a more detailed evaluation of the diet, including calculations of food ingestion. Only 38.7% of the professionals compared child s food ingestion with some recommended pattern. Recommendations for daily ingestion of calcium by children up to the age of 36 months were properly mentioned by 22% of the pediatricians and 60.7% of the nutritionists (p=0.001). Inadequate cow milk substitute products were recommended by 66% of the pediatricians and by 48.3% of the nutritionists. Regarding labels of industrialized products, 81.6% of the pediatricians and 96.4% of the nutritionists advised the parents to look for all terms that could indicate the presence of cow milk protein. CONCLUSIONS: Pediatricians and nutritionists made conceptual errors in their main recommendations regarding the treatment of cow milk protein allergy.OBJETIVO: Avaliar o conhecimento de pediatras e nutricionistas sobre a dieta de exclusão do leite de vaca e seus derivados, com ênfase em questões relacionadas à nutrição da criança. MÉTODOS: Estudo transversal descritivo, do qual participaram pediatras (n=53) e nutricionistas (n=29), vinculados a hospitais públicos do Município de São Paulo, no ano de 2005. Os dados foram coletados por questionário auto-administrado. RESULTADOS: A idade dos profissionais variou de 21 a 50 anos. Quanto ao tempo de graduação, 41,2% eram formados a menos de cinco anos e 91,6% possuíam especialização, mestrado e/ou doutorado. A maioria (97,5%) afirmou avaliar a dieta de crianças submetidas à exclusão do leite de vaca, entretanto, somente 48% o faziam de forma mais detalhadas, incluindo o cálculo da ingestão alimentar. Apenas 38,7% comparam a ingestão alimentar da criança com algum padrão de recomendação. A recomendação diária da ingestão de cálcio para crianças com até 36 meses foi corretamente assinalada por 22% dos pediatras e 60,7% dos nutricionistas (p=0,001). Produtos não adequados como substitutos do leite de vaca seriam recomendados por 66% dos pediatras e 48,3% dos nutricionistas. Com relação à leitura de rótulos de produtos industrializados, 81,6% dos pediatras e 96,4% dos nutricionistas orientam os pais a ler todos os termos que indicam a presença das proteínas do leite de vaca. CONCLUSÕES: Os pediatras e nutricionista demonstraram erro conceitual no que se refere às principais recomendações terapêuticas na alergia às proteínas do leite de vaca.Universidade Federal de São Paulo (UNIFESP)UNIFESPUNIFESPSciEL

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

Identification of a General O-linked Protein Glycosylation System in Acinetobacter baumannii and Its Role in Virulence and Biofilm Formation

Acinetobacter baumannii is an emerging cause of nosocomial infections. The isolation of strains resistant to multiple antibiotics is increasing at alarming rates. Although A. baumannii is considered as one of the more threatening “superbugs” for our healthcare system, little is known about the factors contributing to its pathogenesis. In this work we show that A. baumannii ATCC 17978 possesses an O-glycosylation system responsible for the glycosylation of multiple proteins. 2D-DIGE and mass spectrometry methods identified seven A. baumannii glycoproteins, of yet unknown function. The glycan structure was determined using a combination of MS and NMR techniques and consists of a branched pentasaccharide containing N-acetylgalactosamine, glucose, galactose, N-acetylglucosamine, and a derivative of glucuronic acid. A glycosylation deficient strain was generated by homologous recombination. This strain did not show any growth defects, but exhibited a severely diminished capacity to generate biofilms. Disruption of the glycosylation machinery also resulted in reduced virulence in two infection models, the amoebae Dictyostelium discoideum and the larvae of the insect Galleria mellonella, and reduced in vivo fitness in a mouse model of peritoneal sepsis. Despite A. baumannii genome plasticity, the O-glycosylation machinery appears to be present in all clinical isolates tested as well as in all of the genomes sequenced. This suggests the existence of a strong evolutionary pressure to retain this system. These results together indicate that O-glycosylation in A. baumannii is required for full virulence and therefore represents a novel target for the development of new antibiotics