Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models ...enable aerosol optical properties and cloud condensation nuclei (CCN) concentrations to be determined by fundamental aerosol processes, which should lead to a more physically based simulation of aerosol direct and indirect radiative forcings. This study examines the global variation in particle size distribution simulated by 12 global aerosol microphysics models to quantify model diversity and to identify any common biases against observations. Evaluation against size distribution measurements from a new European network of aerosol supersites shows that the mean model agrees quite well with the observations at many sites on the annual mean, but there are some seasonal biases common to many sites. In particular, at many of these European sites, the accumulation mode number concentration is biased low during winter and Aitken mode concentrations tend to be overestimated in winter and underestimated in summer. At high northern latitudes, the models strongly underpredict Aitken and accumulation particle concentrations compared to the measurements, consistent with previous studies that have highlighted the poor performance of global aerosol models in the Arctic. In the marine boundary layer, the models capture the observed meridional variation in the size distribution, which is dominated by the Aitken mode at high latitudes, with an increasing concentration of accumulation particles with decreasing latitude. Considering vertical profiles, the models reproduce the observed peak in total particle concentrations in the upper troposphere due to new particle formation, although modelled peak concentrations tend to be biased high over Europe. Overall, the multi-model-mean data set simulates the global variation of the particle size distribution with a good degree of skill, suggesting that most of the individual global aerosol microphysics models are performing well, although the large model diversity indicates that some models are in poor agreement with the observations. Further work is required to better constrain size-resolved primary and secondary particle number sources, and an improved understanding of nucleation and growth (e.g. the role of nitrate and secondary organics) will improve the fidelity of simulated particle size distributions.
A 10‐week growth trial was run to evaluate effects of myo‐inositol (MI) on growth performance, haematological parameters, antioxidative capacity and salinity stress tolerance of Litopenaeus vannamei. ...Six practical diets supplemented with graded levels of MI (designated as MI0, MI600, MI1200, MI2400, MI 3600 and MI4800 for 448.8, 974.2, 1568.0, 2810.6, 3835.5 and 4893.6 mg/kg diet, respectively) were fed to six replicate groups of L. vannamei (mean initial body weight 0.63 ± 0.00 g). The results showed that significant increment of growth performance was observed in shrimp fed MI600 diet than those fed MI1200 diet. Lipid concentration in whole body of the shrimp fed MI600 diet was significantly increased. Shrimp fed MI0 diet had lower total protein (TP) as compared to shrimp fed the MI‐supplemented diets (except MI4800 diet). In general, lower activities of antioxidant enzymes and higher malondialdehyde (MDA) content in haemolymph and hepatopancreas were recorded in shrimp fed MI0 diet, compared to those fed the MI‐supplemented diets. Reduced survival after 7‐h salinity stress was present in shrimp fed MI0 diet as compared to those fed MI4800 diet. Dietary MI requirement for glutathione peroxidase activity of L. vannamei was 2705 mg/kg diet.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Rationale
Tandem‐ion mobility spectrometry/mass spectrometry methods have recently gained traction for the structural characterization of proteins and protein complexes. However, ion activation ...techniques currently coupled with tandem‐ion mobility spectrometry/mass spectrometry methods are limited in their ability to characterize structures of proteins and protein complexes.
Methods
Here, we describe the coupling of the separation capabilities of tandem‐trapped ion mobility spectrometry/mass spectrometry (tTIMS/MS) with the dissociation capabilities of ultraviolet photodissociation (UVPD) for protein structure analysis.
Results
We establish the feasibility of dissociating intact proteins by UV irradiation at 213 nm between the two TIMS devices in tTIMS/MS and at pressure conditions compatible with ion mobility spectrometry (2–3 mbar). We validate that the fragments produced by UVPD under these conditions result from a radical‐based mechanism in accordance with prior literature on UVPD. The data suggest stabilization of fragment ions produced from UVPD by collisional cooling due to the elevated pressures used here (“UVnoD2”), which otherwise do not survive to detection. The data account for a sequence coverage for the protein ubiquitin comparable to recent reports, demonstrating the analytical utility of our instrument in mobility‐separating fragment ions produced from UVPD.
Conclusions
The data demonstrate that UVPD carried out at elevated pressures of 2–3 mbar yields extensive fragment ions rich in information about the protein and that their exhaustive analysis requires IMS separation post‐UVPD. Therefore, because UVPD and tTIMS/MS each have been shown to be valuable techniques on their own merit in proteomics, our contribution here underscores the potential of combining tTIMS/MS with UVPD for structural proteomics.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
In a series of 10-day campaigns in Ontario and Quebec, Canada, between 2005 and 2007, ozonesondes were launched twice daily in conjunction with continuous high-resolution wind-profiling radar ...measurements. Windprofilers can measure rapid changes in the height of the tropopause, and in some cases follow stratospheric intrusions. Observed stratospheric intrusions were studied with the aid of a Lagrangian particle dispersion model and the Canadian operational weather forecast system. Definite stratosphere-troposphere transport (STT) events occurred approximately every 2–3 days during the spring and summer campaigns, whereas during autumn and winter, the frequency was reduced to every 4–5 days. Although most events reached the lower troposphere, only three events appear to have significantly contributed to ozone amounts in the surface boundary layer. Detailed calculations find that STT, while highly variable, is responsible for an average, over the seven campaigns, of 3.1% of boundary layer ozone (1.2 ppb), but 13% (5.4 ppb) in the lower troposphere and 34% (22 ppb) in the middle and upper troposphere, where these layers are defined as 0–1 km, 1–3 km, and 3–8 km respectively. Estimates based on counting laminae in ozonesonde profiles, with judicious choices of ozone and relative humidity thresholds, compare moderately well, on average, with these values. The lamina detection algorithm is then applied to a large dataset from four summer ozonesonde campaigns at 18 North American sites between 2006 and 2011. The results show some site-to-site and year-to-year variability, but stratospheric ozone contributions average 4.6% (boundary layer), 15% (lower troposphere) and 26% (middle/upper troposphere). Calculations were also performed based on the TOST global 3D trajectory-mapped ozone data product. Maps of STT in the same three layers of the troposphere suggest that the STT ozone flux is greater over the North American continent than Europe, and much greater in winter and spring than in summer or fall. When averaged over all seasons, magnitudes over North America show similar ratios between levels to the previous calculations, but are overall 3–4 times smaller. This may be because of limitations (trajectory length and vertical resolution) to the current TOST-based calculation.
•Wind-profiling radars measure rapid changes in tropopause height, follow intrusions•STT events every 2–3 days in spring/summer campaigns; every 4–5 days in fall/winters•STT flux estimates from RH laminae compare well with FLEXPART, but only on average•STT ozone flux is greater over North America than Europe
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We have investigated changes in the cation-specific conformational behavior of poly(sodium styrenesulfonate) (PSS) brushes as the solvent changes from water to methanol using a quartz crystal ...microbalance with dissipation (QCM-D). A solvation to desolvation transition of the grafted chains accompanied by swelling to the collapse transition of the brushes is observed for Na+. In the case of Cs+, the brushes undergo solvation to desolvation to resolvation accompanied by swelling to collapse to reswelling transitions. The resolvation and reswelling transitions for Cs+ are induced by the charge inversion of the brushes via van der Waals interactions between Cs+ and the brushes. All of the transitions for monovalent cations become less obvious as the methanol content increases. For divalent Ca2+ and trivalent La3+, a solvation to desolvation to resolvation transition of the grafted chains accompanied by a swelling to collapse to reswelling transition of the brushes can be observed. The resolvation and reswelling of the brushes for the multivalent cations are induced by the charge inversion of the brushes via charge-image charge interactions. The extent of the transitions for the PSS brushes in the presence of multivalent cations is only slightly influenced by the methanol content.
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IJS, KILJ, NUK, PNG, UL, UM
In this investigation, Mg-doped ZnO nanorods were synthesized successfully on a glass substrate at 80 °C by hydrothermal method. The average length and diameter of the Mg-ZnO nanorods were 609 nm and ...approximately 50 nm, respectively. The X-ray diffraction spectrum showed the Mg-ZnO nanorods had a wurtzite hexagonal phase. The Mg-doped ZnO nanorods are found to be single crystals grown along the c-axis. The photosensors showed good stability properties in ultraviolet (UV) illumination. The resulting Mg-doped ZnO nanorods have excellent potential for application in a UV photodetector (PD) because of the Mg-doped ZnO nanorods UV PD has a high UV-to-visible ratio, fast rise/fall time. Furthermore, the dynamic response of the Mg-doped ZnO nanorods PD with Au electrodes was stable and reproducible with an on/off current contrast ratio of approximately 4 × 10 3 . The ultraviolet-to-visible rejection ratio of the sample is approximately 400 when biased at 1 V, and the fabricated UV PD is visible-blind with a sharp cutoff at 350 nm. The low-frequency noise spectra obtained from the UV PD were caused purely by the 1/f noise. The noise-equivalent power and normalized detectivity (D * ) of the Mg-ZnO nanorod PD were 0.335 × 10 -9 W and 1.49 × 10 8 cm · Hz 0.5 · W -1 , respectively.
In this experiment, the influencing factors of tetracycline (TC) removal by adsorption with the aerobic granular sludge-based biochar (BC) were analyzed. In particular, the specific surface area, ...pore size distribution, and functional groups of the biochar were studied. In addition, the kinetics, isotherms, and diffusion models of TC removal were examined. The adsorption of TC reached a maximum (16.59 mg g.sup.-1) when the biochar carbonization temperature and time were 700 degreesC and 2 h, respectively. With increasing initial TC concentration, the adsorption capacity of BC to TC increased gradually. The optimal pH value of TC adsorption with BC was 7.0, and a low concentration of salt was found to promote the adsorption of TC. The pseudo second-order kinetic model and Langmuir isotherm model were found to correlate well the adsorption of TC by BC. Both the internal diffusion and liquid film diffusion were the rate-controlling steps of the adsorption process. The alkali-modified BC was found to be the best adsorbent for TC. Keywords: biochar, tetracycline, aerobic granular sludge, modification
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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