86 research outputs found

    Physics case for an LHCb Upgrade II - Opportunities in flavour physics, and beyond, in the HL-LHC era

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    The LHCb Upgrade II will fully exploit the flavour-physics opportunities of the HL-LHC, and study additional physics topics that take advantage of the forward acceptance of the LHCb spectrometer. The LHCb Upgrade I will begin operation in 2020. Consolidation will occur, and modest enhancements of the Upgrade I detector will be installed, in Long Shutdown 3 of the LHC (2025) and these are discussed here. The main Upgrade II detector will be installed in long shutdown 4 of the LHC (2030) and will build on the strengths of the current LHCb experiment and the Upgrade I. It will operate at a luminosity up to 2×1034 cm−2s−1, ten times that of the Upgrade I detector. New detector components will improve the intrinsic performance of the experiment in certain key areas. An Expression Of Interest proposing Upgrade II was submitted in February 2017. The physics case for the Upgrade II is presented here in more depth. CP-violating phases will be measured with precisions unattainable at any other envisaged facility. The experiment will probe b → sl+l−and b → dl+l− transitions in both muon and electron decays in modes not accessible at Upgrade I. Minimal flavour violation will be tested with a precision measurement of the ratio of B(B0 → μ+μ−)/B(Bs → μ+μ−). Probing charm CP violation at the 10−5 level may result in its long sought discovery. Major advances in hadron spectroscopy will be possible, which will be powerful probes of low energy QCD. Upgrade II potentially will have the highest sensitivity of all the LHC experiments on the Higgs to charm-quark couplings. Generically, the new physics mass scale probed, for fixed couplings, will almost double compared with the pre-HL-LHC era; this extended reach for flavour physics is similar to that which would be achieved by the HE-LHC proposal for the energy frontier

    LHCb upgrade software and computing : technical design report

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    This document reports the Research and Development activities that are carried out in the software and computing domains in view of the upgrade of the LHCb experiment. The implementation of a full software trigger implies major changes in the core software framework, in the event data model, and in the reconstruction algorithms. The increase of the data volumes for both real and simulated datasets requires a corresponding scaling of the distributed computing infrastructure. An implementation plan in both domains is presented, together with a risk assessment analysis

    Measurement of the B0s→μ+μ− Branching Fraction and Effective Lifetime and Search for B0→μ+μ− Decays

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    A search for the rare decays Bs0→μ+μ- and B0→μ+μ- is performed at the LHCb experiment using data collected in pp collisions corresponding to a total integrated luminosity of 4.4  fb-1. An excess of Bs0→μ+μ- decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(Bs0→μ+μ-)=(3.0±0.6-0.2+0.3)×10-9, where the first uncertainty is statistical and the second systematic. The first measurement of the Bs0→μ+μ- effective lifetime, τ(Bs0→μ+μ-)=2.04±0.44±0.05  ps, is reported. No significant excess of B0→μ+μ- decays is found, and a 95% confidence level upper limit, B(B0→μ+μ-)<3.4×10-10, is determined. All results are in agreement with the standard model expectations.A search for the rare decays Bs0μ+μB^0_s\to\mu^+\mu^- and B0μ+μB^0\to\mu^+\mu^- is performed at the LHCb experiment using data collected in pppp collisions corresponding to a total integrated luminosity of 4.4 fb1^{-1}. An excess of Bs0μ+μB^0_s\to\mu^+\mu^- decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(Bs0μ+μ)=(3.0±0.60.2+0.3)×109{\cal B}(B^0_s\to\mu^+\mu^-)=\left(3.0\pm 0.6^{+0.3}_{-0.2}\right)\times 10^{-9}, where the first uncertainty is statistical and the second systematic. The first measurement of the Bs0μ+μB^0_s\to\mu^+\mu^- effective lifetime, τ(Bs0μ+μ)=2.04±0.44±0.05\tau(B^0_s\to\mu^+\mu^-)=2.04\pm 0.44\pm 0.05 ps, is reported. No significant excess of B0μ+μB^0\to\mu^+\mu^- decays is found and a 95 % confidence level upper limit, B(B0μ+μ)<3.4×1010{\cal B}(B^0\to\mu^+\mu^-)<3.4\times 10^{-10}, is determined. All results are in agreement with the Standard Model expectations

    Geochemical Mapping in Europe

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    The Forum of European Geological Surveys (FOREGS) includes Geological Surveys from 34 European countries and is responsible for co-ordinating Geological Survey activities in Europe. The FOREGS Geochemistry Task Group was established in 1994 to supervise European geochemical mapping policy for environmental, legislative, resource-management and scientific purposes. The task group comprises representatives from five countries, charged initially with the compilation of an inventory of geochemical data within FOREGS countries. The preparation of European Geochemical Baseline maps will involve the integration of different national datasets following the recommendations of the International Geological Correlation Programme (IGCP) Project 259 “International Geochemical Mapping”. Results of the inventory show that most geochemical surveys in Europe conform to the IGCP 259 recommendations. Stream sediment (26% coverage), surface water (19% coverage), soil/till (21% coverage) and radiometric data (19% coverage) are the most extensive sample types, and the majority of surveys (81%) have been carried out at sampling densities of ≤ 1 sample per 100 km2. Most filtered-water surveys are based on a filter size of 0.45µm, and 83% of stream sediment surveys collect samples sieved at 100-200 µm. The collection of the Global Reference Network (GRN) samples recommended by IGCP 259 to provide internationally standardised geochemical data and the careful use of statistical and map-generation techniques should facilitate the levelling of different national datasets and preparation of a European Geochemical Baseline

    Staphyloma-induced Serous Maculopathy:Natural Course and Treatment Effects

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    Purpose: To study the natural course of staphyloma-induced serous maculopathy (SISM) and the effects of treatments. Design: Retrospective case series. Participants: This retrospective analysis included 26 eyes of 20 patients with SISM and at least 12 months of follow-up. Methods: Medical records were reviewed for patient demographics, such as age, sex, spherical equivalent, best-corrected visual acuity (BCVA), type of staphyloma, and imaging characteristics. Spectralis OCT B-scans were evaluated for the presence and height of the serous retinal detachment (SRD) at each follow-up visit. An SRD episode was defined as a period with SRD in 1 patient. Main Outcome Measures: Changes in SRD height and BCVA. Results: Twenty-six eyes of 20 patients (70% female) were included. The mean age was 54 ± 11 years, and the mean spherical equivalent was −4.8 ± 3.3 diopters at baseline. The staphyloma was located inferior in 12 eyes (46%), inferonasal in 7 eyes (27%), and nasal in 7 eyes (27%). The mean follow-up duration was 73 ± 34 months. During follow-up, the SRD height fluctuated in all eyes, with a mean change of 125 ± 56 μm. The SRD disappeared completely during follow-up in 13 eyes (50%) and then reappeared in 7 eyes (35%). Resolution occurred spontaneous in 8 eyes (31%). The median time of an SRD episode was 25 (interquartile range 14–57) months. Treatment was performed in 20 eyes (77%) and led to resolution of SRD in 3 of the 15 photodynamic therapy treatments (21%), 2 of 5 (40%) anti-VEGF series, and 2 of 4 eyes (50%) treated with topical prednisolone. Best-corrected visual acuity at the final visit (0.42 ± 0.25) was not significantly different from BCVA at baseline (0.34 ± 0.27 logarithm of the minimum angle of resolution, P = 0.07), nor was BCVA change significantly different between treated eyes (n = 19) and nontreated eyes (n = 7, P = 0.3). Conclusion: Serous retinal detachment in patients with SISM fluctuated over time and resolved without treatment in 31% of the eyes. Because treatment does not change the course of BCVA, a wait-and-see policy is advocated in these patients on the exclusion of treatable causes of SRD. Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.</p

    Anthropogenic Rare Earth Element in rivers: Gadolinium and lanthanum. Partitioning between the dissolved and particulate phases in the Rhine River and spatial propagation through the Rhine-Meuse Delta (the Netherlands)

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    International audienceIn this study, we report for the first time lanthanum and gadolinium anomalies at the catchment scale (Rhine-Meuse River system) together with the partitioning of their anthropogenic contents between the dissolved and the particulate phases. We compare the dissolved and total REE patterns of samples taken at 9 locations in the Rhine Branches including Lobith (situated at the German Dutch border where the Rhine is not yet divided in three Branches), in surface water fed by the Rhine Branches (canals and lake IJsselmeer and Ketelmeer) and 3 locations where the water is derived from the river Meuse (originating from Belgium and France).We demonstrate that the anthropogenic input of lanthanum in the German part of the Rhine River identified by Kulaksiz and Bau (2011) can be traced in the complex Rhine-Meuse Delta up to the North Sea. In the Dutch Branches of the Rhine River, in contrast to the German part of the Rhine River, the anthropogenic lanthanum (La-ANTHRO) is mainly present in the particulate phase (SPM) and not in the dissolved phase (defined as the <0.45 mu m fraction). In the Meuse River no anthropogenic lanthanum was found. The amount of La-ANTHRO transported by the Rhine River at the Lobith station (German-Dutch border) varies from 2008 to 2010 between 3.7 and 5.2 tons/y in the dissolved phase, and between 28.8 and 37.4 tons/y in the particulate phase. However, a big discrepancy is evidenced when we compare the La-ANTHRO load calculated on bases of the total water samples with the La-ANTHRO load calculated as the sum of the particulate and dissolved load: the total La-ANTHRO load is roughly 2 times larger than the La-ANTHRO load calculated as the sum of the dissolved and particulate La-ANTHRO load. The difference between the two calculated fluxes is most likely caused by not sampling the finest fraction of the particulate pool in the SPM samples with an overflow centrifuge.The anthropogenic gadolinium identified by high gadolinium anomalies in the REE patterns originates from numerous point sources (waste water treatment plant effluents) and can thus be considered as diffuse pollution when compared to anthropogenic lanthanum clearly resulting from a single source. The amount of anthropogenic gadolinium measured in the dissolved phase (main carrier of Gd) increases or decreases along the Rhine and Meuse Rivers depending whether or not the mixing water contains anthropogenic gadolinium, i.e. receives waste water effluents

    An ABC Transporter and a TonB Ortholog Contribute to Helicobacter mustelae Nickel and Cobalt Acquisition▿ †

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    The genomes of Helicobacter species colonizing the mammalian gastric mucosa (like Helicobacter pylori) contain a large number of genes annotated as iron acquisition genes but only few nickel acquisition genes, which contrasts with the central position of nickel in the urease-mediated acid resistance of these gastric pathogens. In this study we have investigated the predicted iron and nickel acquisition systems of the ferret pathogen Helicobacter mustelae. The expression of the outer membrane protein-encoding frpB2 gene was iron and Fur repressed, whereas the expression of the ABC transporter genes fecD and ceuE was iron and Fur independent. The inactivation of the two tonB genes showed that TonB1 is required for heme utilization, whereas the absence of TonB2 only marginally affected iron-dependent growth but led to reduced cellular nickel content and urease activity. The inactivation of the fecD and ceuE ABC transporter genes did not affect iron levels but resulted in significantly reduced urease activity and cellular nickel content. Surprisingly, the inactivation of the nixA nickel transporter gene affected cellular nickel content and urease activity only when combined with the inactivation of other nickel acquisition genes, like fecD or ceuE. The FecDE ABC transporter is not specific for nickel, since an fecD mutant also showed reduced cellular cobalt levels and increased cobalt resistance. We conclude that the H. mustelae fecDE and ceuE genes encode an ABC transporter involved in nickel and cobalt acquisition, which works independently of the nickel transporter NixA, while TonB2 is required primarily for nickel acquisition, with TonB1 being required for heme utilization

    Pollution and oral bioaccessibility of Pb in soils of villages and cities with a long habitation history. Special Issue of International Journal of Environmental Research and Public Health

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    The Dutch cities Utrecht and Wijk bij Duurstede were founded by the Romans around 50 B.C. and the village Fijnaart and Graft-De Rijp around 1600 A.D. The soils of these villages are polluted with Pb (up to ~5000 mg/kg). Lead isotope ratios were used to trace the sources of Pb pollution in the urban soils. In ~75% of the urban soils the source of the Pb pollution was a mixture of glazed potsherd, sherds of glazed roof tiles, building remnants (Pb sheets), metal slag, Pb-based paint flakes and coal ashes. These anthropogenic Pb sources most likely entered the urban soils due to historical smelting activities, renovation and demolition of houses, disposal of coal ashes and raising and fertilization of land with city waste. Since many houses still contain Pb-based building materials, careless renovation or demolition can cause new or more extensive Pb pollution in urban soils. In ~25% of the studied urban topsoils, Pb isotope compositions suggest Pb pollution was caused by incinerator ash and/or gasoline Pb suggesting atmospheric deposition as the major source. The bioaccessible Pb fraction of 14 selected urban soils was determined with an in vitro test and varied from 16% to 82% of total Pb. The bioaccessibility appears related to the chemical composition and grain size of the primary Pb phases and pollution age. Risk assessment based on the in vitro test results imply that risk to children may be underestimated in ~90% of the studied sample sites (13 out of 14)
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