Background and purpose: Headache disorders are very common, but their monetary costs in Europe are unknown. We performed the first comprehensive estimation of how economic resources are lost to ...headache in Europe.
Methods: From November 2008 to August 2009, a cross‐sectional survey was conducted in eight countries representing 55% of the adult EU population. Participation rates varied between 11% and 59%. In total, 8412 questionnaires contributed to this analysis. Using bottom‐up methodology, we estimated direct (medications, outpatient health care, hospitalization and investigations) and indirect (work absenteeism and reduced productivity at work) annual per‐person costs. Prevalence data, simultaneously collected and, for migraine, also derived from a systematic review, were used to impute national costs.
Results: Mean per‐person annual costs were €1222 for migraine (95% CI 1055–1389; indirect costs 93%), €303 for tension‐type headache (TTH, 95% CI 230–376; indirect costs 92%), €3561 for medication‐overuse headache (MOH, 95% CI 2487–4635; indirect costs 92%), and €253 for other headaches (95% CI 99–407; indirect costs 82%). In the EU, the total annual cost of headache amongst adults aged 18–65 years was calculated, according to our prevalence estimates, at €173 billion, apportioned to migraine (€111 billion; 64%), TTH (€21 billion; 12%), MOH (€37 billion; 21%) and other headaches (€3 billion; 2%). Using the 15% systematic review prevalence of migraine, calculated costs were somewhat lower (migraine €50 billion, all headache €112 billion annually).
Conclusions: Headache disorders are prominent health‐related drivers of immense economic losses for the EU. This has immediate implications for healthcare policy. Health care for headache can be both improved and cost saving.
Patients receiving anti-platelet agents for secondary cardiovascular prevention frequently require non-cardiac surgery. A substantial proportion of these patients have their anti-platelet drug ...discontinued before operation; however, there is uncertainty about the impact of this practice. The aim of this study was to compare the effect of maintenance or interruption of aspirin before surgery, in terms of major thrombotic and bleeding events.
Patients treated with anti-platelet agents for secondary prevention and undergoing intermediate- or high-risk non-cardiac surgery were included in this multicentre, randomized, placebo-controlled, trial. We substituted non-aspirin anti-platelets with aspirin (75 mg daily) or placebo starting 10 days before surgery. The primary outcome was a composite score evaluating both major thrombotic and bleeding adverse events occurring within the first 30 postoperative days weighted by their severity (weights were established a priori using a Delphi consensus process). Analyses followed the intention-to-treat principle.
We randomized 291 patients (n=145, aspirin group, and n=146, placebo group). The most frequent surgical procedures were orthopaedic surgery (52.2%), abdominal surgery (20.6%), and urologic surgery (15.5%). No significant difference was observed neither in the primary outcome score mean values (sd)=0.67 (2.05) in the aspirin group vs 0.65 (2.04) in the placebo group, P=0.94 nor at day 30 in the number of major complications between groups.
In these at-risk patients undergoing elective non-cardiac surgery, we did not find any difference in terms of occurrence of major thrombotic or bleeding events between preoperative maintenance or interruption of aspirin. ClinicalTrials.gov identifier. NCT00190307.
Understanding changes in the burden and growth rate of atmospheric methane (CH4) has been the focus of several recent studies but still lacks scientific consensus. Here we investigate the role of ...decreasing anthropogenic carbon monoxide (CO) emissions since 2002 on hydroxyl radical (OH) sinks and tropospheric CH4 loss. We quantify this impact by contrasting two model simulations for 2002–2013: (1) a Measurement of the Pollution in the Troposphere (MOPITT) CO reanalysis and (2) a Control‐Run without CO assimilation. These simulations are performed with the Community Atmosphere Model with Chemistry of the Community Earth System Model fully coupled chemistry climate model with prescribed CH4 surface concentrations. The assimilation of MOPITT observations constrains the global CO burden, which significantly decreased over this period by ~20%. We find that this decrease results to (a) increase in CO chemical production, (b) higher CH4 oxidation by OH, and (c) ~8% shorter CH4 lifetime. We elucidate this coupling by a surrogate mechanism for CO‐OH‐CH4 that is quantified from the full chemistry simulations.
Key Points
Decreases in tropospheric CO from 2002 to 2012 indicate an increase in CH4 chemical loss
There is a positive trend in the chemical production of CO from CH4 in the tropics
We infer a reduced growth rate in CH4 burden due to decreases in anthropogenic CO emissions
The specification of state background error statistics is a key component of data assimilation since it affects the impact observations will have on the analysis. In the variational data assimilation ...approach, applied in geophysical sciences, the dimensions of the background error covariance matrix (B) are usually too large to be explicitly determined and B needs to be modeled. Recent efforts to include new variables in the analysis such as cloud parameters and chemical species have required the development of the code to GENerate the Background Errors (GEN_BE) version 2.0 for the Weather Research and Forecasting (WRF) community model. GEN_BE allows for a simpler, flexible, robust, and community-oriented framework that gathers methods used by some meteorological operational centers and researchers. We present the advantages of this new design for the data assimilation community by performing benchmarks of different modeling of B and showing some of the new features in data assimilation test cases. As data assimilation for clouds remains a challenge, we present a multivariate approach that includes hydrometeors in the control variables and new correlated errors. In addition, the GEN_BE v2.0 code is employed to diagnose error parameter statistics for chemical species, which shows that it is a tool flexible enough to implement new control variables. While the generation of the background errors statistics code was first developed for atmospheric research, the new version (GEN_BE v2.0) can be easily applied to other domains of science and chosen to diagnose and model B. Initially developed for variational data assimilation, the model of the B matrix may be useful for variational ensemble hybrid methods as well.
Forest covers 40% of the European Alpine region and contributes to the protection of human beings and infrastructures against natural hazards such as rockfalls. However, despite the recognition of ...this ecosystem service, most mountain territories do not have a map of protection forests. When a map exists, it generally depends on data restricted to a limited extent, which prevents any replication or comparison on other areas. The aim of this study is to develop a method using harmonized and open data to produce the first map of protection forests against rockfalls at the European Alpine region scale. Based on these data, we first identified potential rockfall release areas and calibrated the model according to 2812 real rockfall events located around the Alps. Second, 46.5 billion 3-D rockfall propagation simulations, taking into account topography, land use and human assets, were computed on the entire area. Protection forest is defined as being located on at least one rockfall trajectory that had impacted human assets. Our results show that 14% of the forests have a potential protection function against rockfalls in the Alpine Space region. This proportion goes up to 21.5%, if we consider only the core of the Alpine area. 80% of the protection forest area contributes to mitigate rockfall hazard on road network, 55% on buildings and only 6% on railways. This work provides a robust, objective and reproducible method for locating protection forests on a large geographical scale. Such a map may serve as a basis for national and European risk management policies.
•We identified harmonized open data to model rockfall propagation over European Alps.•46.5 billions rockfall trajectories were computed to identify protection forests.•14% of protection forests in the Alpine region (21.5% in the core of the Alpine area).•80% of protection forests area protect roads, 55% buildings and 6% railways.•Reproducible method and result available for policy makers, foresters and risk managers.
We examine in detail a 1 year global reanalysis of carbon monoxide (CO) that is based on joint assimilation of conventional meteorological observations and Measurement of Pollution in The Troposphere ...(MOPITT) multispectral CO retrievals in the Community Earth System Model (CESM). Our focus is to assess the impact to the chemical system when CO distribution is constrained in a coupled full chemistry‐climate model like CESM. To do this, we first evaluate the joint reanalysis (MOPITT Reanalysis) against four sets of independent observations and compare its performance against a reanalysis with no MOPITT assimilation (Control Run). We then investigate the CO burden and chemical response with the aid of tagged sectoral CO tracers. We estimate the total tropospheric CO burden in 2002 (from ensemble mean and spread) to be 371 ± 12% Tg for MOPITT Reanalysis and 291 ± 9% Tg for Control Run. Our multispecies analysis of this difference suggests that (a) direct emissions of CO and hydrocarbons are too low in the inventory used in this study and (b) chemical oxidation, transport, and deposition processes are not accurately and consistently represented in the model. Increases in CO led to net reduction of OH and subsequent longer lifetime of CH4 (Control Run: 8.7 years versus MOPITT Reanalysis: 9.3 years). Yet at the same time, this increase led to 5–10% enhancement of Northern Hemisphere O3 and overall photochemical activity via HOx recycling. Such nonlinear effects further complicate the attribution to uncertainties in direct emissions alone. This has implications to chemistry‐climate modeling and inversion studies of longer‐lived species.
Key Points
A full year of global reanalysis of CO is evaluated and investigated
Assimilation reveals larger role of hydrocarbon oxidation in the CO burden
Model CH4 lifetime improvement with CO reanalysis points to uncertainties in nonlinear processes
We consider extended slow-fast systems of
N
interacting diffusions. The typical behavior of the empirical density is described by a nonlinear McKean–Vlasov equation depending on
ε
, the scaling ...parameter separating the time scale of the slow variable from the time scale of the fast variable. Its atypical behavior is encapsulated in a large
N
Large Deviation Principle with a rate functional
I
ε
. We study the
Γ
-convergence of
I
ε
as
ε
→
0
and show it converges to the rate functional appearing in the Macroscopic Fluctuations Theory for diffusive systems.
We provide a numerical study of the macroscopic model of Barré et al. (Multiscale Model Simul,
2017
, to appear) derived from an agent-based model for a system of particles interacting through a ...dynamical network of links. Assuming that the network remodeling process is very fast, the macroscopic model takes the form of a single aggregation–diffusion equation for the density of particles. The theoretical study of the macroscopic model gives precise criteria for the phase transitions of the steady states, and in the one-dimensional case, we show numerically that the stationary solutions of the microscopic model undergo the same phase transitions and bifurcation types as the macroscopic model. In the two-dimensional case, we show that the numerical simulations of the macroscopic model are in excellent agreement with the predicted theoretical values. This study provides a partial validation of the formal derivation of the macroscopic model from a microscopic formulation and shows that the former is a consistent approximation of an underlying particle dynamics, making it a powerful tool for the modeling of dynamical networks at a large scale.
We propose a classification of bifurcations of Vlasov equations, based on the strength of the resonance between the unstable mode and the continuous spectrum on the imaginary axis. We then identify ...and characterize a new type of generic bifurcation where this resonance is weak, but the unstable mode couples with a stable mode and a Casimir invariant of the system to form a size-3 Jordan block. We derive a three-dimensional reduced noncanonical Hamiltonian system describing this bifurcation. Comparison of the reduced dynamics with direct numerical simulations on a test case gives excellent agreement. We finally discuss the relevance of this bifurcation to specific physical situations.
We prove that any nonzero inertia, however small, is able to change the nature of the synchronization transition in Kuramoto-like models, either from continuous to discontinuous or from discontinuous ...to continuous. This result is obtained through an unstable manifold expansion in the spirit of Crawford, which features singularities in the vicinity of the bifurcation. Far from being unwanted artifacts, these singularities actually control the qualitative behavior of the system. Our numerical tests fully support this picture.
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