239 research outputs found

    Seven years of marine environmental changes monitoring at coastal OOCS stations (Catalan Sea, NW Mediterranean)

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    Since March 2009 up to the present (more than 7 years now), the Operational Observatory of the Catalan Sea (OOCS; http://www2.ceab.csic.es/ oceans/) remains a witness of persistent marine environmental changes. The OOCS has two fixed observation stations at the head of the Blanes Canyon (200 m depth, 41.66°N; 2.91°E) and at the Blanes bay (20 m depth, 41.67°N; 2.80°E) in the Catalan Sea, NW Mediterranean. At the canyon station, a multi-parametric buoy presently installed delivers high frequency (by 30 min) and multi-parametric oceanographic (i.e. salinity, temperature, chlorophyll, turbidity, as well as light intensity in the PAR range for the upper 50 m depth) and atmospheric (air temperature, relative humidity, wind speed and direction and PAR) data. Subsurface photos and videos by an IP high resolution fisheye camera attached to the buoy are also delivered at 4-hour basis. Data and multimedia are transmitted in near real time for public access, via combined GSM/GPRS and 3G connections. At both stations, CTD profiles and water samples (collected for nutrients and picoplankton analyses) are carried out on board a research vessel at fortnightly basis. Numerical simulations along with the time series of in-situ observations show inter-annual seasonality anomalies possibly linked to global environmental changes. The lower-atmosphere and upper-sea environmental time series data collected prove the occurrence of shifting patterns of heat and matter fluxes impacting pelagic and benthic organisms.Peer Reviewe

    Operational Observatory of the catalan sea (OOCS)

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    The Operational Observatory of the Catalan Sea (OOCS) recently created by the Operational Oceanography Group at CEAB-CSIC is presented. The OOCS aims at performing observations of the marine environment in the Catalan Sea and beyond, assessing, modelling and forecasting the hydrodynamic and biogeochemical processes of the region. Some of the biogeochemical variables available in the models and forecast are phytoplankton, zooplankton and nutrients. Although OOCS is expected to be fully operational in 2011, some of its services are already available to the public through a dedicated webpage http://www.ceab.csic.es/~simob/.Peer Reviewe

    Single-electron transport driven by surface acoustic waves: moving quantum dots versus short barriers

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    We have investigated the response of the acoustoelectric current driven by a surface-acoustic wave through a quantum point contact in the closed-channel regime. Under proper conditions, the current develops plateaus at integer multiples of ef when the frequency f of the surface-acoustic wave or the gate voltage Vg of the point contact is varied. A pronounced 1.1 MHz beat period of the current indicates that the interference of the surface-acoustic wave with reflected waves matters. This is supported by the results obtained after a second independent beam of surface-acoustic wave was added, traveling in opposite direction. We have found that two sub-intervals can be distinguished within the 1.1 MHz modulation period, where two different sets of plateaus dominate the acoustoelectric-current versus gate-voltage characteristics. In some cases, both types of quantized steps appeared simultaneously, though at different current values, as if they were superposed on each other. Their presence could result from two independent quantization mechanisms for the acoustoelectric current. We point out that short potential barriers determining the properties of our nominally long constrictions could lead to an additional quantization mechanism, independent from those described in the standard model of 'moving quantum dots'.Comment: 25 pages, 12 figures, to be published in a special issue of J. Low Temp. Phys. in honour of Prof. F. Pobel

    Sequential screening nominates the Parkinson's disease associated kinase LRRK2 as a regulator of Clathrin-mediated endocytosis

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    Mutations in leucine-rich repeat kinase 2 (LRRK2) are an established cause of inherited Parkinson's disease (PD). LRRK2 is expressed in both neurons and glia in the central nervous system, but its physiological function(s) in each of these cell types is uncertain. Through sequential screens, we report a functional interaction between LRRK2 and Clathrin adaptor protein complex 2 (AP2). Analysis of LRRK2 KO tissue revealed a significant dysregulation of AP2 complex components, suggesting LRRK2 may act upstream of AP2. In line with this hypothesis, expression of LRRK2 was found to modify recruitment and phosphorylation of AP2. Furthermore, expression of LRRK2 containing the R1441C pathogenic mutation resulted in impaired clathrin-mediated endocytosis (CME). A decrease in activity-dependent synaptic vesicle endocytosis was also observed in neurons harboring an endogenous R1441C LRRK2 mutation. Alongside LRRK2, several PD-associated genes intersect with membrane-trafficking pathways. To investigate the genetic association between Clathrin-trafficking and PD, we used polygenetic risk profiling from IPDGC genome wide association studies (GWAS) datasets. Clathrin-dependent endocytosis genes were found to be associated with PD across multiple cohorts, suggesting common variants at these loci represent a cumulative risk factor for disease. Taken together, these findings suggest CME is a LRRK2-mediated, PD relevant pathway.Neurological Motor Disorder

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

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    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

    An updated radiocarbon-based ice margin chronology for the last deglaciation of the North American Ice Sheet Complex

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    The North American Ice Sheet Complex (NAISC; consisting of the Laurentide, Cordilleran and Innuitian ice sheets) was the largest ice mass to repeatedly grow and decay in the Northern Hemisphere during the Quaternary. Understanding its pattern of retreat following the Last Glacial Maximum is critical for studying many facets of the Late Quaternary, including ice sheet behaviour, the evolution of Holocene landscapes, sea level, atmospheric circulation, and the peopling of the Americas. Currently, the most up-to-date and authoritative margin chronology for the entire ice sheet complex is featured in two publications (Geological Survey of Canada Open File 1574 [Dyke et al., 2003]; ‘Quaternary Glaciations – Extent and Chronology, Part II’ [Dyke, 2004]). These often-cited datasets track ice margin recession in 36 time slices spanning 18 ka to 1 ka (all ages in uncalibrated radiocarbon years) using a combination of geomorphology, stratigraphy and radiocarbon dating. However, by virtue of being over 15 years old, the ice margin chronology requires updating to reflect new work and important revisions. This paper updates the aforementioned 36 ice margin maps to reflect new data from regional studies. We also update the original radiocarbon dataset from the 2003/2004 papers with 1541 new ages to reflect work up to and including 2018. A major revision is made to the 18 ka ice margin, where Banks and Eglinton islands (once considered to be glacial refugia) are now shown to be fully glaciated. Our updated 18 ka ice sheet increased in areal extent from 17.81 to 18.37 million km2, which is an increase of 3.1% in spatial coverage of the NAISC at that time. Elsewhere, we also summarize, region-by-region, significant changes to the deglaciation sequence. This paper integrates new information provided by regional experts and radiocarbon data into the deglaciation sequence while maintaining consistency with the original ice margin positions of Dyke et al. (2003) and Dyke (2004) where new information is lacking; this is a pragmatic solution to satisfy the needs of a Quaternary research community that requires up-to-date knowledge of the pattern of ice margin recession of what was once the world’s largest ice mass. The 36 updated isochrones are available in PDF and shapefile format, together with a spreadsheet of the expanded radiocarbon dataset (n = 5195 ages) and estimates of uncertainty for each interval

    The global, regional, and national burden of inflammatory bowel disease in 195 countries and territories, 1990-2017 : a systematic analysis for the Global Burden of Disease Study 2017

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    Background The burden of inflammatory bowel disease (IBD) is rising globally, with substantial variation in levels and trends of disease in different countries and regions. Understanding these geographical differences is crucial for formulating effective strategies for preventing and treating IBD. We report the prevalence, mortality, and overall burden of IBD in 195 countries and territories between 1990 and 2017, based on data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017. Methods We modelled mortality due to IBD using a standard Cause of Death Ensemble model including data mainly from vital registrations. To estimate the non-fatal burden, we used data presented in primary studies, hospital discharges, and claims data, and used DisMod-MR 2.1, a Bayesian meta-regression tool, to ensure consistency between measures. Mortality, prevalence, years of life lost (YLLs) due to premature death, years lived with disability (YLDs), and disability-adjusted life-years (DALYs) were estimated. All of the estimates were reported as numbers and rates per 100 000 population, with 95% uncertainty intervals (UI). Findings In 2017, there were 6.8 million (95% UI 6.4-7.3) cases of IBD globally. The age-standardised prevalence rate increased from 79.5 (75.9-83.5) per 100 000 population in 1990 to 84.3 (79.2-89.9) per 100 000 population in 2017. The age-standardised death rate decreased from 0.61 (0.55-0.69) per 100 000 population in 1990 to 0.51 (0.42-0.54) per 100 000 population in 2017. At the GBD regional level, the highest age-standardised prevalence rate in 2017 occurred in high-income North America (422.0 [398.7-446.1] per 100 000) and the lowest age-standardised prevalence rates were observed in the Caribbean (6.7 [6.3-7.2] per 100 000 population). High Sociodemographic Index (SDI) locations had the highest age-standardised prevalence rate, while low SDI regions had the lowest age-standardised prevalence rate. At the national level, the USA had the highest age-standardised prevalence rate (464.5 [438.6-490.9] per 100 000 population), followed by the UK (449.6 [420.6-481.6] per 100 000). Vanuatu had the highest age-standardised death rate in 2017 (1.8 [0.8-3.2] per 100 000 population) and Singapore had the lowest (0.08 [0.06-0.14] per 100 000 population). The total YLDs attributed to IBD almost doubled over the study period, from 0.56 million (0.39-0.77) in 1990 to 1.02 million (0.71-1.38) in 2017. The age-standardised rate of DALYs decreased from 26.5 (21.0-33.0) per 100 000 population in 1990 to 23.2 (19.1-27.8) per 100 000 population in 2017. Interpretation The prevalence of IBD increased substantially in many regions from 1990 to 2017, which might pose a substantial social and economic burden on governments and health systems in the coming years. Our findings can be useful for policy makers developing strategies to tackle IBD, including the education of specialised personnel to address the burden of this complex disease. Copyright (C) 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

    The global, regional, and national burden of inflammatory bowel disease in 195 countries and territories, 1990�2017: a systematic analysis for the Global Burden of Disease Study 2017

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    Background: The burden of inflammatory bowel disease (IBD) is rising globally, with substantial variation in levels and trends of disease in different countries and regions. Understanding these geographical differences is crucial for formulating effective strategies for preventing and treating IBD. We report the prevalence, mortality, and overall burden of IBD in 195 countries and territories between 1990 and 2017, based on data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017. Methods: We modelled mortality due to IBD using a standard Cause of Death Ensemble model including data mainly from vital registrations. To estimate the non-fatal burden, we used data presented in primary studies, hospital discharges, and claims data, and used DisMod-MR 2.1, a Bayesian meta-regression tool, to ensure consistency between measures. Mortality, prevalence, years of life lost (YLLs) due to premature death, years lived with disability (YLDs), and disability-adjusted life-years (DALYs) were estimated. All of the estimates were reported as numbers and rates per 100 000 population, with 95 uncertainty intervals (UI). Findings: In 2017, there were 6·8 million (95 UI 6·4�7·3) cases of IBD globally. The age-standardised prevalence rate increased from 79·5 (75·9�83·5) per 100 000 population in 1990 to 84·3 (79·2�89·9) per 100 000 population in 2017. The age-standardised death rate decreased from 0·61 (0·55�0·69) per 100 000 population in 1990 to 0·51 (0·42�0·54) per 100 000 population in 2017. At the GBD regional level, the highest age-standardised prevalence rate in 2017 occurred in high-income North America (422·0 398·7�446·1 per 100 000) and the lowest age-standardised prevalence rates were observed in the Caribbean (6·7 6·3�7·2 per 100 000 population). High Socio-demographic Index (SDI) locations had the highest age-standardised prevalence rate, while low SDI regions had the lowest age-standardised prevalence rate. At the national level, the USA had the highest age-standardised prevalence rate (464·5 438·6�490·9 per 100 000 population), followed by the UK (449·6 420·6�481·6 per 100 000). Vanuatu had the highest age-standardised death rate in 2017 (1·8 0·8�3·2 per 100 000 population) and Singapore had the lowest (0·08 0·06�0·14 per 100 000 population). The total YLDs attributed to IBD almost doubled over the study period, from 0·56 million (0·39�0·77) in 1990 to 1·02 million (0·71�1·38) in 2017. The age-standardised rate of DALYs decreased from 26·5 (21·0�33·0) per 100 000 population in 1990 to 23·2 (19·1�27·8) per 100 000 population in 2017. Interpretation: The prevalence of IBD increased substantially in many regions from 1990 to 2017, which might pose a substantial social and economic burden on governments and health systems in the coming years. Our findings can be useful for policy makers developing strategies to tackle IBD, including the education of specialised personnel to address the burden of this complex disease. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

    Effects of Intermittent IL-2 Alone or with Peri-Cycle Antiretroviral Therapy in Early HIV Infection: The STALWART Study

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    The Study of Aldesleukin with and without antiretroviral therapy (STALWART) evaluated whether intermittent interleukin-2 (IL-2) alone or with antiretroviral therapy (ART) around IL-2 cycles increased CD4+ counts compared to no therapy
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