Ionic liquids (ILs) have gained considerable attention in recent years as CO2-reactive solvents that could be used to improve the economic efficiency of industrial-scale CO2 separations. Researchers ...have demonstrated that IL physical and chemical properties can be optimized for a given application through chemical functionalization of both cations and anions. The tunability of ILs presents both a great potential and a significant challenge due to the complex chemistries and the many ways in which ILs can be made to react with CO2. However, computer simulations have demonstrated great potential in understanding the behavior of ILs from the underlying molecular interactions. In the present review, we examine how computer simulations have aided in the design of ILs that chemically bind CO2. We present the historical development of CO2-reactive ILs while highlighting the insights provided by molecular modeling which aided in understanding IL behavior to further experimental findings. We also provide a brief discussion of simulations focused on ionic liquids that physically dissolve CO2. We conclude with a discussion of areas where simulations can yet be used to advance the current understanding of these complex systems and an outlook on the use of computer simulations in the design of optimal ILs for CO2 separations.
The upcoming Ice, Cloud and Land Elevation Satellite-2 (ICESat-2) mission will offer prospects for mapping and monitoring biomass and carbon of terrestrial ecosystems over large areas using photon ...counting LiDAR data. In this paper, we aim to develop a methodology to derive terrain elevation and vegetation canopy height from test-bed sensor data and further pre-validate the capacity of the mission to meet its science objectives for the ecosystem community. We investigated a novel methodological framework with two essential steps for characterizing terrain and canopy height using Multiple Altimeter Beam Experimental LiDAR (MABEL) data and simulated ICESat-2 data with various vegetation conditions. Our algorithm first implements a multi-level noise filtering approach to minimize noise photons and subsequently classifies the remaining photons into ground and top of canopy using an overlapping moving window method and cubic spline interpolation. Results of noise filtering show that the design of the multi-level filtering process is effective to identify background noise and preserve signal photons in the raw data. Moreover, calibration results using MABEL and simulated ICESat-2 data share similar trends with the retrieved terrain being more accurate than the retrieved canopy height, and the nighttime results being better than corresponding daytime results. Compared to the results of simulated ICESat-2 data, MABEL data achieve lower accuracy for ground and canopy heights in terms of root mean square error (RMSE), which may partly result from the inconsistency between MABEL and reference data. Specifically, simulated ICESat-2 data using 115 various nighttime and daytime scenarios, yield average RMSE values of 1.83 m and 2.80 m for estimated ground elevation, and 2.70 m and 3.59 m for estimated canopy height. Additionally, the accuracy assessment of percentile heights of simulated ICESat-2 data further substantiates the robustness of the methodology from different perspectives. The methodology developed in this study illustrates plausible ways of processing the data that are structurally similar to expected ICESat-2 data and holds the potential to be a benchmark for further method adjustment once genuine ICESat-2 are available.
•An adaptive methodological framework was developed to process upcoming ICESat-2 data.•Basic algorithms for ground and canopy photon classification with ICESat-2-like data.•Terrain and canopy height measurements with MABEL and simulated ICESat-2 data.
While progress has been made in characterizing humoral immunity to Zika virus (ZIKV) in humans, little is known regarding the corresponding T cell responses to ZIKV. Here, we investigate the kinetics ...and viral epitopes targeted by T cells responding to ZIKV and address the critical question of whether preexisting dengue virus (DENV) T cell immunity modulates these responses. We find that memory T cell responses elicited by prior infection with DENV or vaccination with tetravalent dengue attenuated vaccines (TDLAV) recognize ZIKV-derived peptides. This cross-reactivity is explained by the sequence similarity of the two viruses, as the ZIKV peptides recognized by DENV-elicited memory T cells are identical or highly conserved in DENV and ZIKV. DENV exposure prior to ZIKV infection also influences the timing and magnitude of the T cell response. ZIKV-reactive T cells in the acute phase of infection are detected earlier and in greater magnitude in DENV-immune patients. Conversely, the frequency of ZIKV-reactive T cells continues to rise in the convalescent phase in DENV-naive donors but declines in DENV-preexposed donors, compatible with more efficient control of ZIKV replication and/or clearance of ZIKV antigen. The quality of responses is also influenced by previous DENV exposure, and ZIKV-specific CD8 T cells from DENV-preexposed donors selectively upregulated granzyme B and PD1, unlike DENV-naive donors. Finally, we discovered that ZIKV structural proteins (E, prM, and C) are major targets of both the CD4 and CD8 T cell responses, whereas DENV T cell epitopes are found primarily in nonstructural proteins.
The issue of potential ZIKV and DENV cross-reactivity and how preexisting DENV T cell immunity modulates Zika T cell responses is of great relevance, as the two viruses often cocirculate and Zika virus has been spreading in geographical regions where DENV is endemic or hyperendemic. Our data show that memory T cell responses elicited by prior infection with DENV recognize ZIKV-derived peptides and that DENV exposure prior to ZIKV infection influences the timing, magnitude, and quality of the T cell response. Additionally, we show that ZIKV-specific responses target different proteins than DENV-specific responses, pointing toward important implications for vaccine design against this global threat.
Computational tools to search chemical structure databases are essential to finding leads early in a drug discovery project. Similarity methods are among the most diverse and most useful. We will ...present some lessons we have gathered over many years experience with in-house methods on several therapeutic problems. The effectiveness of any similarity method can vary greatly from one biological activity to another in a way that is difficult to predict. Also, any two methods tend to select different subsets of actives from a database, so it is advisable to use several search methods where possible.
SUMMARY
Eosinophilic esophagitis (EoE) is diagnosed by symptoms, and at least 15 intraepithelial eosinophils per high power field in an esophageal biopsy. Other pathologic features have not been ...emphasized. We developed a histology scoring system for esophageal biopsies that evaluates eight features: eosinophil density, basal zone hyperplasia, eosinophil abscesses, eosinophil surface layering, dilated intercellular spaces (DIS), surface epithelial alteration, dyskeratotic epithelial cells, and lamina propria fibrosis. Severity (grade) and extent (stage) of abnormalities were scored using a 4-point scale (0 normal; 3 maximum change). Reliability was demonstrated by strong to moderate agreement among three pathologists who scored biopsies independently (P ≤ 0.008). Several features were often abnormal in 201 biopsies (101 distal, 100 proximal) from 104 subjects (34 untreated, 167 treated). Median grade and stage scores were significantly higher in untreated compared with treated subjects (P ≤ 0.0062). Grade scores for features independent of eosinophil counts were significantly higher in biopsies from untreated compared with treated subjects (basal zone hyperplasia P ≤ 0.024 and DIS P ≤ 0.005), and were strongly correlated (R-square >0.67). Principal components analysis identified three principal components that explained 78.2% of the variation in the features. In logistic regression models, two principal components more closely associated with treatment status than log distal peak eosinophil count (PEC) (R-square 17, area under the curve (AUC) 77.8 vs. R-square 9, AUC 69.8). In summary, the EoE histology scoring system provides a method to objectively assess histologic changes in the esophagus beyond eosinophil number. Importantly, it discriminates treated from untreated patients, uses features commonly found in such biopsies, and is utilizable by pathologists after minimal training. These data provide rationales and a method to evaluate esophageal biopsies for features in addition to PEC.
•Detailed analysis of aroma-active compounds in white wines with ‘stone fruit’ aroma.•First aroma profile of Viognier wine by GC-O.•Monoterpenes might be of major importance for ‘stone fruit’ aroma ...in Viognier wine.•Clarification of Viognier being classified as an aromatic terpene-rich variety.
Despite numerous studies, the identity of the compounds that are responsible for ‘stone fruit’ aroma in wine has not been conclusively established. This study focussed on wine varieties that often display peach and apricot characters, such as Chardonnay, Viognier and botrytis-affected sweet Semillon wines. Wines with high and low ‘stone fruit’ aroma were evaluated by gas chromatography-olfactometry-mass spectrometry (GC-O-MS) using extracts representative of the aroma of the wine in a glass. No aroma-active zone was described as ‘stone fruit’ aroma across all three wine varietals. However, for the individual varieties, terpenes, such as linalool and geraniol, in the Viognier wines, several esters in the Chardonnay wines, and γ-nonalactone in the botrytis Semillon were associated with ‘stone fruit’ aroma. Notably, this is the first study assessing the aroma profile of Viognier wine by GC-O. In addition, an extension study of Viognier grape monoterpene profiles clarified its classification as an aromatic variety.
Sintered NdFeB-based scrap magnets were recovered and processed using the HD and HDDR routes. The effects of varying the HDDR processing temperature were investigated (over the range 835–930°C). The ...disproportion was carried out with a pressure ramp to a maximum of 1000mbar hydrogen pressure with a 1h hold time at each step and the optimum recombination conditions were set at 100mbar with a 20min hold time. Anisotropic NdFeB powder was produced in all cases with the best magnetic properties achieved at a processing temperature of 880°C, producing powder with a remanence of 1.10(±0.02)T and an intrinsic coercivity of 800 (±16)kAm−1 and giving a (BH)max of 129(±2.5)kJm−3.
► Production of anisotropic permanent magnet powder from scrap NdFeB magnets by HDDR. ► Reaction pressure increases with increasing processing temperature. ► Best magnetic properties achieved by processing at 880°C.
PDF
