During LBA‐CLAIRE‐98, we found atmospheric layers with aged biomass smoke at altitudes >10 km over Suriname. CO, CO2, acetonitrile, methyl chloride, hydrocarbons, NO, O3, and aerosols were strongly ...enhanced in these layers. We estimate that 80–95% of accumulation mode aerosols had been removed during convective transport. Trajectories show that the plumes originated from large fires near the Brazil/Venezuela border during March 1998. This smoke was entrained into deep convection over the northern Amazon, transported out over the Pacific, and then returned to South America by the circulation around a large upper‐level anticyclone. Our observations provide evidence for the importance of deep convection in the equatorial region as a mechanism to transport large amounts of pyrogenic pollutants into the upper troposphere. The entrainment of biomass smoke into tropical convective clouds may have significant effects on cloud microphysics and climate dynamics.
One of the main uncertainties in the estimation of the climatic impact of aerosols is linked to our knowledge of gas and aerosol emissions. This is particularly crucial over Asia, where a strong ...regional fingerprint is observed, with different emission types, depending on the various vegetation and climate conditions (biomass burning emissions) and on the very fast changes of the population and industrialization (biofuel and fossil fuel emissions). The main contribution of this work is to derive a biomass burning inventory of 1° × 1° over Asia (the Asian biomass burning inventory (ABBI)) for gases and particles for the Aerosol Characterization Experiment‐Asia (ACE‐Asia) and Transport and Chemical Evolution Over the Pacific (TRACE‐P) campaign period (March to May 2001) in 2001. In this paper we apply new estimates of burnt biomass area to estimate emissions. The method is based on burnt areas (GBA2000 project; Tansey et al. (2002) and Grégoire et al. (2003)) obtained from 1 km resolution SPOT‐VEGETATION satellite data. Regional‐scale maps of burnt areas are produced, and then spatial and temporal emission distribution are obtained from biomass density and emission factors. Strength and weaknesses associated with the use of satellite products are discussed, including the problem of subpixel classification and the lack of validation data for the accuracy assessment of the products for the studied area. Estimated emissions are compared with ACE‐Asia and TRACE‐P Modeling and Emission Support System (ACESS) climatological estimates. In addition, interannual variability is estimated by preparing inventories for the years 2000 and 2001.
We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies ...and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter epsilon(mu tau). The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041 <= epsilon(mu tau) <= 0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.
Whether to continue oral anticoagulant therapy beyond 6 months after an "unprovoked" venous thromboembolism is controversial. We sought to determine clinical predictors to identify patients who are ...at low risk of recurrent venous thromboembolism who could safely discontinue oral anticoagulants.
In a multicentre prospective cohort study, 646 participants with a first, unprovoked major venous thromboembolism were enrolled over a 4-year period. Of these, 600 participants completed a mean 18-month follow-up in September 2006. We collected data for 69 potential predictors of recurrent venous thromboembolism while patients were taking oral anticoagulation therapy (5-7 months after initiation). During follow-up after discontinuing oral anticoagulation therapy, all episodes of suspected recurrent venous thromboembolism were independently adjudicated. We performed a multivariable analysis of predictor variables (p < 0.10) with high interobserver reliability to derive a clinical decision rule.
We identified 91 confirmed episodes of recurrent venous thromboembolism during follow-up after discontinuing oral anticoagulation therapy (annual risk 9.3%, 95% CI 7.7%-11.3%). Men had a 13.7% (95% CI 10.8%-17.0%) annual risk. There was no combination of clinical predictors that satisfied our criteria for identifying a low-risk subgroup of men. Fifty-two percent of women had 0 or 1 of the following characteristics: hyperpigmentation, edema or redness of either leg; D-dimer > or = 250 microg/L while taking warfarin; body mass index > or = 30 kg/m(2); or age > or = 65 years. These women had an annual risk of 1.6% (95% CI 0.3%-4.6%). Women who had 2 or more of these findings had an annual risk of 14.1% (95% CI 10.9%-17.3%).
Women with 0 or 1 risk factor may safely discontinue oral anticoagulant therapy after 6 months of therapy following a first unprovoked venous thromboembolism. This criterion does not apply to men.
The scientific community dealing with modelling of emissions of greenhouse gases and aerosols from anthropogenic sources demands reliable and quantitative information on the magnitude of biomass ...burning at a global scale. It is in this context that the Global Burnt Area -- 2000 (GBA2000) initiative has been launched. The specific objectives of this initiative are to produce a map of the areas burnt globally for the year 2000, using the medium resolution (1.1 km) Système Pour l'Observation de la Terre (SPOT) 4-VEGETATION (SPOT-VGT) satellite imagery and to derive statistics of area burnt per country, per month and per main type of vegetation cover. A series of regional algorithms has been developed and incorporated into a data processing system designed to yield monthly estimates of areas burnt at a global scale. The map data will then be transformed into quantitative information and made publicly available over the World Wide Web at a range of spatial and temporal resolutions to satisfy some of the requirements of the atmospheric and climate change modelling community.
IMPORTANCE: While the prevalence of age-related macular degeneration (AMD) differs according to continents and races/ethnicities, its incidence in the European continent has been scarcely documented. ...OBJECTIVE: To describe the incidence and associated risk factors of AMD in elderly French individuals. DESIGN, SETTING, AND PARTICIPANTS: This population-based cohort study of 963 residents of Bordeaux, France, who were 73 years or older at baseline and participated in the Antioxydants, Lipides Essentiels, Nutrition et Maladies Oculaires (ALIENOR) Study between October 2, 2006, and December 21, 2012. Of 829 participants at risk for incident AMD, 659 (79.5%) were observed for a mean (SD) duration of 3.8 (1.1) years. Data were analyzed from August 2016 to March 2017. MAIN OUTCOMES AND MEASURES: Age-related macular degeneration was graded from retinal photographs and spectral-domain optical coherence tomography into 5 exclusive stages: no AMD, early AMD1, early AMD2, late atrophic AMD, and late neovascular AMD. RESULTS: Of the 659 eligible participants, 413 (62.7%) were women, and the mean (SD; range) age was 79.7 (4.4; 73-94) years. A total of 120 incident cases of early AMD and 45 incident cases of advanced AMD were recorded. Incidence rates of early and advanced AMD were 79.9 (95% CI, 66.8-95.5) per 1000 person-years and 18.6 (95% CI, 13.9-24.9) per 1000 person-years, respectively, corresponding to 5-year risks of 32.9% and 8.9%. Incidence of advanced AMD per 1000 eye-years was 1.5 in eyes without any AMD at baseline, 42.4 in those with early AMD1, and 85.1 in those with early AMD2. In multivariate analysis without correction for multiple testing, progression from early to advanced AMD was associated with AMD grade in the fellow eye (hazard ratio HR according to grade, 13.0 95% CI, 2.8-61.2 to 22.5 95% CI, 2.6-195.9), having smoked at least 20 pack-years (calculated as number of smoking years × mean number of cigarettes per day / 20; HR, 3.0; 95% CI, 1.4-6.5), and complement factor H (CFH) Y402H genotype (CC genotype: HR, 2.3; 95% CI, 1.0-5.3; TC genotype: HR, 1.5; 95% CI, 0.6-3.7). Incidence of early AMD was associated with early AMD in the fellow eye (early AMD1: HR, 2.6; 95% CI, 1.6-4.2; early AMD2: HR, 5.6; 95% CI, 3.3-9.4) and high plasma high-density lipoprotein cholesterol levels (HR, 1.2; 95% CI, 1.0-1.4). CONCLUSIONS AND RELEVANCE: In this cohort, AMD incidence rates were similar to those observed in other European populations. This study suggests a high risk for incident early AMD in individuals with high plasma high-density lipoprotein cholesterol levels while confirming the high risk for progression from early to advanced AMD in heavy smokers and carriers of CFH Y402H at-risk genotypes.
This paper outlines the first part of a series of research studies to investigate the potential and approaches for using optical remote sensing to assess vegetation water content. It first analyzes ...why most methods used as approximations of vegetation water content (such as vegetation stress indices, estimation of degree of curing and chlorophyll content) are not suitable for retrieving water content at leaf level. It then documents the physical basis supporting the use of remote sensing to directly detect vegetation water content in terms of Equivalent Water Thickness (EWT) at leaf level. Using laboratory measurements, the radiative transfer model PROSPECT and a sensitivity analysis, it shows that shortwave infrared (SWIR) is sensitive to EWT but cannot be used alone to retrieve EWT because two other leaf parameters (internal structure and dry matter) also influence leaf reflectance in the SWIR. A combination of SWIR and NIR (only influenced by these two parameters) is necessary to retrieve EWT at leaf level. These results set the basis towards establishing operational techniques for the retrieval of EWT at top-of-canopy and top-of-atmospheric levels.
Observations of the time-dependent cosmic-ray Sun shadow have been proven as a valuable diagnostic for the assessment of solar magnetic field models. In this paper, seven years of IceCube data are ...compared to solar activity and solar magnetic field models. A quantitative comparison of solar magnetic field models with IceCube data on the event rate level is performed for the first time. Additionally, a first energy-dependent analysis is presented and compared to recent predictions. We use seven years of IceCube data for the moon and the Sun and compare them to simulations on data rate level. The simulations are performed for the geometrical shadow hypothesis for the moon and the Sun and for a cosmic-ray propagation model governed by the solar magnetic field for the case of the Sun. We find that a linearly decreasing relationship between Sun shadow strength and solar activity is preferred over a constant relationship at the 6.4σ level. We test two commonly used models of the coronal magnetic field, both combined with a Parker spiral, by modeling cosmic-ray propagation in the solar magnetic field. Both models predict a weakening of the shadow in times of high solar activity as it is also visible in the data. We find tensions with the data on the order of 3σ for both models, assuming only statistical uncertainties. The magnetic field model CSSS fits the data slightly better than the PFSS model. This is generally consistent with what is found previously by the Tibet AS−γ Experiment; a deviation of the data from the two models is, however, not significant at this point. Regarding the energy dependence of the Sun shadow, we find indications that the shadowing effect increases with energy during times of high solar activity, in agreement with theoretical predictions.
Summary
Background
Post‐thrombotic syndrome (PTS) is the most frequent complication of deep vein thrombosis (DVT). Its diagnosis is based on clinical characteristics. However, symptoms and signs of ...PTS are non‐specific, and could result from concomitant primary venous insufficiency (PVI) rather than DVT. This could bias evaluation of PTS.
Methods
Using data from the REVERSE multicenter study, we assessed risk factors for PTS in patients with a first unprovoked unilateral proximal DVT 5–7 months earlier who were free of clinically significant PVI (defined as absence of moderate or severe venous ectasia in the contralateral leg).
Results
Among the 328 patients considered, the prevalence of PTS was 27.1%. Obesity (odds ratio OR 2.6 95% confidence interval (CI) 1.5–4.7), mild contralateral venous ectasia (OR 2.2 95% CI 1.1–4.3), poor International Normalized Ratio (INR) control (OR per additional 1% of time with INR < 2 during anticoagulant treatment of 1.018 95% CI 1.003–1.034) and the presence of residual venous obstruction on ultrasound (OR 2.1 95% CI 1.1–3.7) significantly increased the risk for PTS in multivariable analyses. When we restricted our analysis to patients without any signs, even mild, of contralateral venous insufficiency (n = 244), the prevalence of PTS decreased slightly to 24.6%. Only obesity remained an independent predictor of PTS (OR 2.6 95% CI 1.3–5.0). Poor INR control and residual venous obstruction also increased the risk, but the results were no longer statistically significant (OR 1.017 95% CI 0.999–1.035 and OR 1.7 95% CI 0.9–3.3, respectively).
Conclusions
After a first unprovoked proximal DVT, obese patients and patients with even mild PVI constitute a group at increased risk of developing PTS for whom particular attention should be paid with respect to PTS prevention. Careful monitoring of anticoagulant treatment may prevent PTS.
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