As a contribution to phase2 of the Air Quality Model Evaluation International Initiative (AQMEII), eight different simulations for the year 2010 were performed with WRF-Chem for the European domain. ...The four simulations using RADM2 gas-phase chemistry and the MADE/SORGAM aerosol module are analyzed in this paper. The simulations included different degrees of aerosol–meteorology feedback, ranging from no aerosol effects at all to the inclusion of the aerosol direct radiative effect as well as aerosol cloud interactions and the aerosol indirect effect. In addition, a modification of the RADM2 gas phase chemistry solver was tested. The yearly simulations allow characterizing the average impact of the consideration of feedback effects on meteorology and pollutant concentrations and an analysis of the seasonality. Pronounced feedback effects were found for the summer 2010 Russian wildfire episode, where the direct aerosol effect lowered the seasonal mean solar radiation by 20 W m−3 and seasonal mean temperature by 0.25°. This might be considered as a lower limit as it must be taken into account that aerosol concentrations were generally underestimated by up to 50%. The high aerosol concentrations from the wildfires resulted in a 10%–30% decreased precipitation over Russia when aerosol cloud interactions were taken into account. The most pronounced and persistent feedback due to the indirect aerosol effect was found for regions with very low aerosol concentrations like the Atlantic and Northern Europe. The low aerosol concentrations in this area result in very low cloud droplet numbers between 5 and 100 droplets cm−1 and a 50–70% lower cloud liquid water path. This leads to an increase in the downward solar radiation by almost 50%. Over Northern Scandinavia, this results in almost one degree higher mean temperatures during summer. In winter, the decreased liquid water path resulted in increased long-wave cooling and a decrease of the mean temperature by almost the same amount. Precipitation over the Atlantic Ocean was found to be enhanced by up to 30% when aerosol cloud interactions were taken into account. The inclusion of aerosol cloud interactions can reduce the bias or improve correlations of simulated precipitation for some episodes and regions. However, the domain and time averaged performance statistics do not indicate a general improvement when aerosol feedbacks are taken into account. Except for conditions with either very low or very high aerosol concentrations, the impact of aerosol feedbacks on pollutant distributions was found to be smaller than the effect of the choice of the chemistry module or wet deposition implementation.
•We compare four WRF-Chem simulations which contributed to AQMEII phase2.•Simulations include different degrees of aerosol–radiation feedback and aerosol cloud interactions.•Lower solar radiation, temperature, PBL height, and ozone with direct aerosol effect.•With aerosol cloud interactions higher solar radiation for clean conditions.•Neutral on average performance except for very low aerosol concentrations.
The structure, stability, and vibrational properties of isolated V2O5 clusters on the Al2O3(0001) surface have been studied by density functional theory and statistical thermodynamics. The most ...stable structure does not possess vanadyl oxygen atoms. The positions of the oxygen atoms are in registry with those of the alumina support, and both vanadium atoms occupy octahedral sites. Another structure with one vanadyl oxygen atom is only 0.12 eV less stable. Infrared spectra are calculated for the two structures. The highest frequency at 922 cm-1 belongs to a V−O stretch in the V−O−Al interface bonds, which supports the assignment of such a mode to the band observed around 941 cm-1 for vanadia particles on alumina. Removal of a bridging oxygen atom from the most stable cluster at the V−O−Al interface bond costs 2.79 eV. Removal of a (vanadyl) oxygen atom from a thin vanadia film on α-Al2O3 costs 1.3 eV more, but removal from a V2O5(001) single-crystal surface costs 0.9 eV less. Similar to the V2O5(001) surface, the facile reduction is due to substantial structure relaxations that involve formation of an additional V−O−V bond and yield a pair of VIV(d) sites instead of a VIII(d)/VV(d0) pair.
Atmospheric aerosols modify the radiative budget of the Earth due to their optical, microphysical and chemical properties, and are considered one of the most uncertain climate forcing agents. In ...order to characterise the uncertainties associated with satellite and modelling approaches to represent aerosol optical properties, mainly aerosol optical depth (AOD) and Ångström exponent (AE), their representation by different remote-sensing sensors and regional online coupled chemistry–climate models over Europe are evaluated. This work also characterises whether the inclusion of aerosol–radiation (ARI) or/and aerosol–cloud interactions (ACI) help improve the skills of modelling outputs.Two case studies were selected within the EuMetChem COST Action ES1004 framework when important aerosol episodes in 2010 all over Europe took place: a Russian wildfire episode and a Saharan desert dust outbreak that covered most of the Mediterranean Sea. The model data came from different regional air-quality–climate simulations performed by working group 2 of EuMetChem, which differed according to whether ARI or ACI was included or not. The remote-sensing data came from three different sensors: MODIS, OMI and SeaWIFS. The evaluation used classical statistical metrics to first compare satellite data versus the ground-based instrument network (AERONET) and then to evaluate model versus the observational data (both satellite and ground-based data).Regarding the uncertainty in the satellite representation of AOD, MODIS presented the best agreement with the AERONET observations compared to other satellite AOD observations. The differences found between remote-sensing sensors highlighted the uncertainty in the observations, which have to be taken into account when evaluating models. When modelling results were considered, a common trend for underestimating high AOD levels was observed. For the AE, models tended to underestimate its variability, except when considering a sectional approach in the aerosol representation. The modelling results showed better skills when ARI+ACI interactions were included; hence this improvement in the representation of AOD (above 30 % in the model error) and AE (between 20 and 75 %) is important to provide a better description of aerosol–radiation–cloud interactions in regional climate models.
Measuring muscle fatigue and resistance to fatigue is a topical theme in many clinical research studies. Multi-domain approaches, including electromyography (EMG), are employed to measure fatigue in ...rehabilitation contexts. In particular, spectral features, such as the reduction in the median frequency, are accepted biomarkers to detect muscle fatigue conditions. However, applications of fatigue detection in clinical scenarios are still limited and with margin for improvement. One of the potential applications of such methodology in clinics concerns the evaluation of the rehabilitation after hip fracture. In this work, 20 inpatients, in the acute phase after hip fracture surgery and with lower limb weakness, performed isometric contractions with their healthy lower limb (quadriceps muscle) and their resistance to fatigue before and after 2 weeks of rehabilitation program was measured. Multi-channel EMG and Maximum Voluntary Contractions (MVC, force) were recorded on five muscle heads. We found that, after performing the same number of repetitions (repetitions pre-treatment: 19.7 ± 1.34; repetitions post-treatment: 19.9 ± 0.36; p = 0.223), MVC improved (MVC pre-treatment: 278 ± 112 N; MVC post-treatment: 322 ± 88 N; p = 0.015) after rehabilitation for most of the patients and fatigue did not change. These results suggest that higher force exertion was performed after rehabilitation, with the same level of fatigue (fatigued muscles pre-treatment: 1.40 ± 1.70; fatigued muscles post-treatment: 1.15 ± 1.59; p = 0.175) after. Results are discussed addressing the potential of multifactorial instrumental assessments for describing patients’ status and provide data for clinical decision making.
The determination of the state of resident space objects (RSOs) is fundamental to maintain a collision-free environment in space, predict space events and perform space activities. Due to the ...development of new sensor technologies and the ever-growing number of RSOs, the number of observations available is increasing by the day. In addition, the nature of the observations makes it very difficult to obtain a precise state of the object with only one passage of the object over the observing station. For this reason, the problem of data association becomes relevant: one has to find multiple observations of the same RSO to precisely determine its orbit. Depending on the length and precision of observations, dedicated solutions need to be developed. In this research uncertainty regions associated to the states of RSOs are semi-analytically defined through Taylor expansions, thus making not necessary point-wise sampling or dynamics simplification. This is enabled by differential algebra (DA). For very short and/or uncertain observations, a DA version of the Admissible Region (AR) from literature is defined and an efficient filter is developed for the automatic recognition of chains of observations. This filter includes a new figure of merit (FoM) for the association problem based on range intersection. When observations are long enough to allow for an initial orbit determination (IOD) solution, a new algorithm which defines the uncertainty region without a-priori constraints is developed. The main result within this framework is the definition of a clear working boundary between AR and IOD approaches depending on the optical observing strategy adopted. An advanced Monte Carlo simulation (MCS) is then employed to perform data association as intersection of the uncertainty regions defined. For longer observations where orbit determination (OD) can be performed, an optimisation routine which decouples the principal directions of the uncertainty is developed for efficient propagation and uncertainty update. Results show that the decoupling alleviates the necessity of tuning the FoM for association. Finally, the influence of different coordinate systems on uncertainty propagation is studied. It is found that not only the computation time is affected, but the absorbtion of nonlinearities in the dynamics is highly dependent on the integration variable chosen.
This study describes how the complete mitogenome of a terrestrial snail, Cylindrus obtusus (Draparnaud, 1805) was sequenced without PCRs from a collection specimen that had been in 70% ethanol for 8 ...years. The mitogenome was obtained with Illumina GAIIx shot gun sequencing. Although the used specimen was collected relatively recently and kept in a DNA-friendly preservative (not formalin as frequently used with old museum specimens), we believe that the exclusion of PCRs as facilitated by NGS (Next Generation Sequencing) removes a great obstacle in DNA sequencing of collection specimens. A brief comparison is made between our Illumina GAIIx approach and a similar study that made use of the Roche 454-FLX platform.
The mtDNA sequence of C. obtusus is 14,610 bases in length (about 0.5 kb larger than other stylommatophoran mitogenomes reported hitherto) and contains the 37 genes (13 protein coding genes, two rRNAs and 22 tRNAs) typical for metazoans. Except for a swap between the position of tRNA-Pro and tRNA-Ala, the gene arrangement of C. obtusus is identical to that reported for Cepaea nemoralis. The 'aberrant' rearrangement of tRNA-Thr and COIII compared to that of other Sigmurethra (and the majority of gastropods), is not unique for C. nemoralis (subfamily Helicinae), but is also shown to occur in C. obtusus (subfamily Ariantinae) and might be a synapomorphy for the family Helicidae.
Natural history collections potentially harbor a wealth of information for the field of evolutionary genetics, but it can be difficult to amplify DNA from such specimens (due to DNA degradation for instance). Because NGS techniques do not rely on primer-directed amplification (PCR) and allow DNA to be fragmented (DNA gets sheared during library preparation), NGS could be a valuable tool for retrieving DNA sequence data from such specimens. A comparison between Illumina GAIIx and the Roche 454 platform suggests that the former might be more suited for de novo sequencing of mitogenomes.
A new sensitivity analysis with the Comprehensive Air Quality Model with Extensions (CAMx) using a traditional two-product scheme (SOAP) and the newer Volatility Basis Set (VBS) algorithm for organic ...aerosol (OA) calculations is presented. The sensitivity simulations include the default versions of the SOAP and VBS schemes, as well as new parametrizations for the VBS scheme to calculate emissions and volatility distributions of semi- and intermediate-volatile organic compounds. The focus of the simulations is the summer season (May to July 2013), in order to quantify the sensitivity of the model in a period with relatively large photochemical activity. In addition to the model sensitivity, we validate the results with ad hoc OA measurements obtained from aerosol mass spectrometers at two monitoring sites. Unlike winter cases previously published, the comparison with experimental data showed limited sensitivity to total OA amount, with an estimated increase in OA concentrations limited to a few tenths of µg m−3, for both the primary and secondary components. We show that the lack of pronounced sensitivity is related to the effect of the new parametrizations on different emissions sectors. Furthermore, the minor sensitivity to the new parametrizations could be related to the greater partitioning of OA towards the gaseous phase in the summer period, thus reducing the organic fraction in the aerosol phase.
Myelin oligodendrocyte glycoprotein is a protein exclusively expressed on the surface of oligodendrocytes and myelin in the central nervous system. Antibodies against myelin oligodendrocyte ...glycoprotein were initially detected in children with demyelinating syndromes, and more recently reported in a broad spectrum of central nervous system demyelinating diseases in adults, including neuromyelitis optica spectrum disorders and bilateral optic neuritis. Patients with myelin oligodendrocyte glycoprotein antibody-associated demyelination appear to have unique clinical and radiological features. To the best of our knowledge a series of Italian patients with optic neuritis and positivity to myelin oligodendrocyte glycoprotein antibodies has not yet been reported and the paper on myelin oligodendrocyte glycoprotein antibodies are more focused on clinical features, diagnosis and outcome than on the radiological appearance, so we want to retrospectively report magnetic resonance imaging features of a group of eight patients, who came to our Ophthalmologic Emergency Department for optic neuritis and were found seropositive for myelin oligodendrocyte glycoprotein antibodies, comparing our data with the findings described in the literature.
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