97 research outputs found
Experimental Measurements and Correlation of the Solubility of Three Primary Amides in Supercritical CO2: Acetanilide, Propanamide, and Butanamide
Solubilities of three primary amides, namely, acetanilide, propanamide, and butanamide, in supercritical carbon dioxide were measured at T = (308.2, 313.2, and 323.2) K over the pressure range (9.0 to 40.0) MPa by a flow type apparatus. The solubility behavior of the three solids shows an analogous trend with a crossover region of the respective isotherms between (12 to 14) MPa. The solubility of each amide, at the same temperature and pressure, decreases from propanamide to acetanilide. Pure compound properties required for the modeling were estimated, and the solubilities of the amides were correlated by using the Soave-Redlich-Kwong cubic equation of state with an absolute average relative deviation (AARD) from (1.3 to 6.1) %
Ammonium hydrogen (RS)-[(5-methyl-2-oxo-1,3-oxazolidin-3-yl)methyl]phosphonate
In the title compound, NH4
+·C5H9NO5P−, the five-membered methyloxazolidin-2-one unit is disordered over two positions, the major component having a site occupancy of 0.832 (9). A three-dimensional network of O—H⋯O and N—H⋯O hydrogen bonds stabilizes the crystal structure
The 2.4 Å cryo-EM structure of a heptameric light-harvesting 2 complex reveals two carotenoid energy transfer pathways
We report the 2.4 Ångström resolution structure of the light-harvesting 2 (LH2) complex from Marichromatium (Mch.) purpuratum determined by cryogenic electron microscopy. The structure contains a heptameric ring that is unique among all known LH2 structures, explaining the unusual spectroscopic properties of this bacterial antenna complex. We identify two sets of distinct carotenoids in the structure and describe a network of energy transfer pathways from the carotenoids to bacteriochlorophyll a molecules. The geometry imposed by the heptameric ring controls the resonant coupling of the long-wavelength energy absorption band. Together, these details reveal key aspects of the assembly and oligomeric form of purple bacterial LH2 complexes that were previously inaccessible by any technique
Spin Caloritronics
This is a brief overview of the state of the art of spin caloritronics, the
science and technology of controlling heat currents by the electron spin degree
of freedom (and vice versa).Comment: To be published in "Spin Current", edited by S. Maekawa, E. Saitoh,
S. Valenzuela and Y. Kimura, Oxford University Pres
Sharing of carbapenemase-encoding plasmids between Enterobacteriaceae in UK sewage uncovered by MinION sequencing
Dissemination of carbapenem resistance among pathogenic Gram-negative bacteria is a looming medical emergency. Efficient spread of resistance within and between bacterial species is facilitated by mobile genetic elements. We hypothesized that wastewater contributes to the dissemination of carbapenemase-producing Enterobacteriaceae (CPE), and studied this through a cross-sectional observational study of wastewater in the East of England. We isolated clinically relevant species of CPE in untreated and treated wastewater, confirming that waste treatment does not prevent release of CPE into the environment. We observed that CPE-positive plants were restricted to those in direct receipt of hospital waste, suggesting that hospital effluent may play a role in disseminating carbapenem resistance. We postulated that plasmids carrying carbapenemase genes were exchanged between bacterial hosts in sewage, and used short-read (Illumina) and long-read (MinION) technologies to characterize plasmids encoding resistance to antimicrobials and heavy metals. We demonstrated that different CPE species ( and ) isolated from wastewater from the same treatment plant shared two plasmids of 63 and 280 kb. The former plasmid conferred resistance to carbapenems (), and the latter to numerous drug classes and heavy metals. We also report the complete genome sequence for . Small, portable sequencing instruments such as the MinION have the potential to improve the quality of information gathered on antimicrobial resistance in the environment.This publication presents independent research supported by the Health Innovation Challenge Fund (WT098600, HICF-T5-342), a parallel funding partnership between the Department of Health, UK, and the Wellcome Trust. C. L. is a Wellcome Trust Sir Henry Postdoctoral Fellow (110243/Z/15/Z). T. G. is a Wellcome Trust Research Training Fellow (103387/Z/13/Z)
Experience of Application of the ELISA Method for Detection of Antibodies to Ebola Virus during the SAET Team Work in the Republic of Guinea
The aim of the work was to develop a kit for detection of IgM and IgG antibodies to Ebola virus in ELISA.Materials and methods. Ebola virus strain Zaire H.sapiens-wt/GIN/2015/Kalidie-Kindia-1022 grown on cell culture was used as antigen.Results and conclusions. The kit was used by the Rospotrebnadzor SAET team in its work in Guinea while investigating cases during Ebola fever epidemics. It was established that specific IgG antibodies persisted in Ebola fever survivors for 2 years. Application of this kit in the laboratory diagnostics permits ELISA to become the main and confirmatory laboratory method of Ebola fever detection
Studies of West Nile Virus Circulation in the Territory of the Saratov Region in 2010
Presented are the results of ecological and epizootiological surveillance of the territory of the Saratov region, which was carried out in autumn of 2010. The surveillance was aimed at detection of West Nile (WN) virus circulation and premises for WN Fever natural focus formation. It is demonstrated that in 2010 WN virus circulation took place in damp biotopes of the Saratov region territory, and that common species of small mammals were involved in it. Presented are the results of analysis of the WN virus role in the infectious pathology in the territory of the Saratov region
Need for speed: Examining protein behavior during cryoEM grid preparation at different timescales
A host of new technologies are under development to improve the quality and reproducibility of cryoelectron microscopy (cryoEM) grid preparation. Here we have systematically investigated the preparation of three macromolecular complexes using three different vitrification devices (Vitrobot, chameleon, and a time-resolved cryoEM device) on various timescales, including grids made within 6 ms (the fastest reported to date), to interrogate particle behavior at the air-water interface for different timepoints. Results demonstrate that different macromolecular complexes can respond to the thin-film environment formed during cryoEM sample preparation in highly variable ways, shedding light on why cryoEM sample preparation can be difficult to optimize. We demonstrate that reducing time between sample application and vitrification is just one tool to improve cryoEM grid quality, but that it is unlikely to be a generic “silver bullet” for improving the quality of every cryoEM sample preparation
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