Aerosol physical and optical properties were measured at two locations in northern India. The first measurement station was a background site in Mukteshwar, about 350 km northeast of New Delhi, in ...the foothills of the Indian Himalayas, with data from 2006 to 2009. The second measurement site was located in Gual Pahari, about 25 km south of New Delhi, with data from 2008 to 2009. At both stations, the average aerosol concentrations during the monsoon were decreased by 40–75 % compared to the pre-monsoon average concentrations. The decrease varied with the total local rainfall. In Mukteshwar, the monsoon season removed particles from all size classes, due to a combination of rain scavenging and activation to cloud and mountain fog droplets. The scavenging by rain is least effective for the size range of the accumulation mode particles. In Gual Pahari, this was the only major wet removal mechanism and, as a result, the accumulation mode particles were less effectively removed. Aerosol concentrations during the early monsoon were found to be affected by mineral dust which in Gual Pahari was observed as an increased particle volume at a diameter around 3–4 μm. The single scattering albedo varied from 0.73 to 0.93 during the monsoon season, being slightly lower in Gual Pahari than in Mukteshwar. This is due to the fact that Gual Pahari resided closer to high anthropogenic black carbon emissions. As the absorbing particles are typically in the accumulation mode, they were not effectively removed by rain scavenging. The aerosol columnar properties, which were measured in Gual Pahari, showed a somewhat different seasonal behaviour compared to the surface measurements, with the aerosol optical depth increasing to an annual maximum in the early monsoon season.
We have studied the photoinduced low spin (LS) to high spin (HS) conversion of Fe(bipy)(3)(2+) in aqueous solution. In a laser pump/X-ray probe synchrotron setup permitting simultaneous, ...time-resolved X-ray diffuse scattering (XDS) and X-ray spectroscopic measurements at a 3.26 MHz repetition rate, we observed the interplay between intramolecular dynamics and the intermolecular caging solvent response with better than 100 ps time resolution. On this time scale, the initial ultrafast spin transition and the associated intramolecular geometric structure changes are long completed, as is the solvent heating due to the initial energy dissipation from the excited HS molecule. Combining information from X-ray emission spectroscopy and scattering, the excitation fraction as well as the temperature and density changes of the solvent can be closely followed on the subnanosecond time scale of the HS lifetime, allowing the detection of an ultrafast change in bulk solvent density. An analysis approach directly utilizing the spectroscopic data in the XDS analysis effectively reduces the number of free parameters, and both combined permit extraction of information about the ultrafast structural dynamics of the caging solvent, in particular, a decrease in the number of water molecules in the first solvation shell is inferred, as predicted by recent theoretical work.
Rituximab is a third-line option for refractory generalized myasthenia gravis (MG) based on empirical evidence, but its effect in new-onset disease is unknown.
To investigate the efficacy and safety ...of rituximab compared with placebo as an add-on to standard of care for MG.
This randomized, double-blind, placebo-controlled study took place throughout 48 weeks at 7 regional clinics in Sweden. Key inclusion criteria were age older than 18 years, onset of generalized symptoms within 12 months or less, and a Quantitative Myasthenia Gravis (QMG) score of 6 or more. Patients were screened from October 20, 2016, to March 2, 2020. Key exclusion criteria included pure ocular MG, suspected thymoma, previous thymectomy, and prior noncorticosteroid immunosuppressants or high doses of corticosteroids.
Participants were randomized 1:1 without stratification to a single intravenous infusion of 500 mg of rituximab or matching placebo.
Minimal disease manifestations at 16 weeks defined as a QMG score of 4 or less with prednisolone, 10 mg or less daily, and no rescue treatment.
Of 87 potentially eligible patients, 25 were randomized to rituximab (mean SD age, 67.4 13.4 years; 7 28% female) and 22 to placebo (mean SD age, 58 18.6 years; 7 32% female). Compared with placebo, a greater proportion with rituximab met the primary end point; 71% (17 of 24) in the rituximab group vs 29% (6 of 21) in the placebo group (Fisher exact test P = .007; probability ratio, 2.48 95% CI, 1.20-5.11). Secondary end points, comparing changes in Myasthenia Gravis Activities of Daily Living and Myasthenia Gravis Quality of Life at 16 weeks with QMG at 24 weeks did not differ between groups with censoring for rescue treatment (per-protocol analysis) but were in favor of active treatment when rescue treatment was taken into account by worst rank imputation (post hoc analysis). Rescue treatments were also more frequent in the placebo arm (rituximab: 1 4%; placebo, 8 36%). One patient in the placebo arm had a myocardial infarction with cardiac arrest and 1 patient in the active arm experienced a fatal cardiac event.
A single dose of 500 mg of rituximab was associated with greater probability of minimal MG manifestations and reduced need of rescue medications compared with placebo. Further studies are needed to address long-term benefit-risk balance with this treatment.
ClinicalTrials.gov Identifier: NCT02950155.
In May–June 2019, smoke plumes from wildfires in Alberta, Canada, were advected all the way to Europe. To analyze the evolution of the plumes and to estimate the amount of smoke aerosols transported ...to Europe, retrievals from the spaceborne lidar CALIOP (Cloud-Aerosol LIdar with Orthogonal Polarization) were used. The plumes were located with the help of a trajectory analysis, and the masses of smoke aerosols were retrieved from the CALIOP observations. The accuracy of the CALIOP mass retrievals was compared with the accuracy of ground-based lidars/ceilometer near the source in North America and after the long-range transport in Europe. Overall, CALIOP and the ground-based lidars/ceilometer produced comparable results. Over North America the CALIOP layer mean mass was 30 % smaller than the ground-based estimates, whereas over southern Europe that difference varied between 12 % and 43 %. Finally, the CALIOP mass retrievals were compared with simulated aerosol concentrations from two reanalysis models: MERRA-2 (Modern-Era Retrospective analysis for Research and Applications, Version 2) and CAMS (Copernicus Atmospheric Monitoring System). The simulated total column aerosol optical depths (AODs) and the total column mass concentration of smoke agreed quite well with CALIOP observations, but the comparison of the layer mass concentration of smoke showed significant discrepancies. The amount of smoke aerosols in the model simulations was consistently smaller than in the CALIOP retrievals. These results highlight the limitations of such models and more specifically their limitation to reproduce properly the smoke vertical distribution. They indicate that CALIOP is a useful tool monitoring smoke plumes over secluded areas, whereas reanalysis models have difficulties in representing the aerosol mass in these plumes. This study shows the advantages of spaceborne aerosol lidars, e.g., being of paramount importance to monitor smoke plumes, and reveals the urgent need of future lidar missions in space.
To be able to meet global grand challenges (climate change; biodiversity loss; environmental pollution; scarcity of water, food and energy supplies; acidification; deforestation; chemicalization; ...pandemics), which all are closely interlinked with each other, we need comprehensive open data with proper metadata, along with open science. The large data sets from ground-based in situ observations, ground and satellite remote sensing, and multiscale modeling need to be utilized seamlessly. In this opinion paper, we demonstrate the power of the SMEAR (Station for Measuring Earth surface–Atmosphere Relations) concept via several examples, such as detection of new particle formation and the particles' subsequent growth, quantifying atmosphere–ecosystem feedback loops, and combining comprehensive observations with emergency science and services, as well as studying the effect of COVID-19 restrictions on different air quality and climate variables. The future needs and the potential of comprehensive observations of the environment are summarized.
Although increased aerosol concentration modifies local air temperatures and boundary layer structure in urban areas, little is known about its effects on the urban hydrological cycle. Changes in the ...hydrological cycle modify surface runoff and flooding. Furthermore, as runoff commonly transports pollutants to soil and water, any changes impact urban soil and aquatic environments. To explore the radiative effect of haze on changes in the urban surface water balance in Beijing, different haze levels are modelled using the Surface Urban Energy and Water Balance Scheme (SUEWS), forced by reanalysis data. The pollution levels are classified using aerosol optical depth observations. The secondary aims are to examine the usability of a global reanalysis dataset in a highly polluted environment and the SUEWS model performance.
There is a concern that topical tacrolimus and pimecrolimus, indicated for second-line treatment of atopic dermatitis, may increase the risk of lymphoma and skin cancer, particularly in children.
The ...aim of this study was to compare incidence rates (IRs) of lymphoma and skin cancer between new users of topical tacrolimus or pimecrolimus and users of moderate- to high-potency topical corticosteroids (TCSs) and untreated subjects.
This is a multicenter cohort study with frequency matching by strata of propensity scores in population databases in the Netherlands, Denmark, Sweden, and the UK. IR ratios (IRRs) were estimated using Mantel-Haenszel methods for stratified analysis.
We included 19,948 children and 66,127 adults initiating tacrolimus, 23,840 children and 37,417 adults initiating pimecrolimus, 584,121 users of TCSs, and 257,074 untreated subjects. IRs of lymphoma per 100,000 person-years were 10.4 events in children and 41.0 events in adults using tacrolimus and 3.0 events in children and 27.0 events in adults using pimecrolimus. The IRR (95% confidence interval CI) for lymphoma, tacrolimus versus TCSs, was 3.74 (1.00-14.06) in children and 1.27 (0.94-1.71) in adults. By lymphoma type, the highest IRR was 3.17 (0.58-17.23) for Hodgkin lymphoma in children and 1.76 (95% CI, 0.81-3.79) for cutaneous T-cell lymphoma (CTCL) in adults. For pimecrolimus versus TCSs, the highest IRR was 1.31 (95% CI, 0.33-5.14) for CTCL in adults. Compared with untreated subjects, adults using TCSs had a higher incidence of CTCL (IRR, 10.66; 95% CI, 2.60-43.75). Smaller associations were found between tacrolimus and pimecrolimus use and the risk of malignant melanoma or nonmelanoma skin cancer.
Use of topical tacrolimus and pimecrolimus was associated with an increased risk of lymphoma. The low IRs imply that even if the increased risk is causal, it represents a small excess risk for individual patients. Residual confounding by severity of atopic dermatitis, increased monitoring of severe patients, and reverse causation could have affected the results.
The Atlantic herring (Clupea harengus), one of the most abundant marine fishes in the world, has historically been a critical food source in Northern Europe. It is one of the few marine species that ...can reproduce throughout the brackish salinity gradient of the Baltic Sea. Previous studies based on few genetic markers have revealed a conspicuous lack of genetic differentiation between geographic regions, consistent with huge population sizes and minute genetic drift. Here, we present a cost-effective genome-wide study in a species that lacks a genome sequence. We first assembled a muscle transcriptome and then aligned genomic reads to the transcripts, creating an “exome assembly,” capturing both exons and flanking sequences. We then resequenced pools of fish from a wide geographic range, including the Northeast Atlantic, as well as different regions in the Baltic Sea, aligned the reads to the exome assembly, and identified 440,817 SNPs. The great majority of SNPs showed no appreciable differences in allele frequency among populations; however, several thousand SNPs showed striking differences, some approaching fixation for different alleles. The contrast between low genetic differentiation at most loci and striking differences at others implies that the latter category primarily reflects natural selection. A simulation study confirmed that the distribution of the fixation index F ST deviated significantly from expectation for selectively neutral loci. This study provides insights concerning the population structure of an important marine fish and establishes the Atlantic herring as a model for population genetic studies of adaptation and natural selection.
Satellites offer the opportunity to determine the spatial distribution of aerosol properties. In this study the AATSR (Advanced Along Track Scanning Radiometer) Dual View (ADV) algorithm is applied ...for observing aerosol optical depth (AOD) over Eastern China. A preliminary selection of representative aerosol models was made by a comparison of ADV retrieval for a range of models with AERONET data. The selected fine-, and coarse-mode aerosol models were subsequently used in the ADV retrievals over a wider area where no AERONET data was available. In addition to AOD at wavelengths of 0.555 and 0.659μm, a mixing ratio (the contribution of fine mode aerosol to the total aerosol extinction) was retrieved from the AATSR data for 2008. The results show a seasonal variation of the AODs and mixing ratios over the areas with strong anthropogenic activity; over rural areas the AODs and mixing ratios are low throughout the year. Over urban areas the lowest AODs were observed during the winter, and the highest during the summer. During the winter the fine mode aerosol mixing ratios were higher than during other seasons.
► The AATSR retrievals over Eastern China show seasonal variation of the AODs over areas having strong athropogenic activity. ► Over urban areas the highest AODs are observed during summer, and lowest during winter. ► Over rural areas the AODs remain low troughout the year. ► The contribution of the fine mode particles to the total AOD is over 70% over most part of the Eastern China.
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