Archives, Room Use Only - TK5123.V35 1845

Archives, Room Use Only - QC517.V92 1927

Archives, Room Use Only - TK5243.M7 A33 1914

Archives, Room Use Only - TA140.B75 R62 1965

Archives, Room Use Only - TK5265.L37 1859

Archives, Room Use Only - TK5243.M7 N53 1938

Archives, Room Use Only - PN6175.E54 1854

Archives, Room Use Only - QC521.B35 1857

Archives, Room Use Only - TK140.E3 D34 1894

Archives, Room Use Only - TK6162.R33 1917

Archives, Room Use Only - TK5243.M7 S66 1955

Archives, Room Use Only - TF627.K57 1904

Archives, Room Use Only - Q164.T5713 1890

Archives, Room Use Only - HE7797.W55 C36 1956

Archives, Room Use Only - TK5243.M7 A33 1972

Archives, Room Use Only - TK5295.N38 1895

Archives, Room Use Only - TK5295.W47 1875

Archives, Room Use Only - PZ7.S8467 T45 1956

Archives, Room Use Only - TK5123.V35 1847

Archives, Room Use Only - TK5445.T37 1889

Archives, Room Use Only - TK5115.R45 1919

Archives, Room Use Only - PS3539.A14 C52 1915

Archives, Room Use Only - HE7797.W53 R58 1950

Archives, Room Use Only - UG590.S54 1838

Archives, Room Use Only - QC527.T73 1895

Administrator of BTC holds review meet

A simple random sampling provides each individual comprising the population the same probability of inclusion in the sample. Such a sampling technique has been adopted in some European countries

THANJAVUR The All India Trade Union Congress will be organising a demonstration on May 11 to press the Union and State governments to expedite the pro

The Trump administration is tightening visa guidelines for Chinese journalists in response to the treatment of US journalists in China, as tensions flare between the two nations over the coronavirus.

Hong Kong: Trump administration tightens visas for Chinese reporters - Times of India

With confusion prevailing over opening of shops, the district administration has issued clarification and released list of shops that can be opened an

Research Centre Finance Administrator job with UNIVERSITY OF LEEDS | 206139  Times Higher Education (THE)

In the context of increasing hardware and software automation in the process of crystal structure determination by X-ray diffraction, and based on conference sessions presenting some of the experience of senior crystallographers for the benefit of younger colleagues, an outline is given here of some basic concepts and applications of symmetry in crystallography. Three specific examples of structure determinations are discussed, for which an understanding of these aspects of symmetry avoids mistakes that can readily be made by reliance on automatic procedures. Topics addressed include pseudo-symmetry, twinning, real and apparent disorder, chirality, and structure validation.

The data quality requirements for charge density studies on actinide compounds are extreme. Important steps in data collection and reduction required to obtain such data are summarized and evaluated. The steps involved in building an augmented Hansen–Coppens multipole model for an actinide pseudo-atom are provided. The number and choice of radial functions, in particular the definition of the core, valence and pseudo-valence terms are discussed. The conclusions in this paper are based on a re-examination and improvement of a previously reported study on [PPh4][UF6]. Topological analysis of the total electron density shows remarkable agreement between experiment and theory; however, there are significant differences in the Laplacian distribution close to the uranium atoms which may be due to the effective core potential employed for the theoretical calculations.

100 kV is investigated as the operating voltage for single-particle electron cryomicroscopy (cryoEM). Reducing the electron energy from the current standard of 300 or 200 keV offers both cost savings and potentially improved imaging. The latter follows from recent measurements of radiation damage to biological specimens by high-energy electrons, which show that at lower energies there is an increased amount of information available per unit damage. For frozen hydrated specimens around 300 Å in thickness, the predicted optimal electron energy for imaging is 100 keV. Currently available electron cryomicroscopes in the 100–120 keV range are not optimized for cryoEM as they lack both the spatially coherent illumination needed for the high defocus used in cryoEM and imaging detectors optimized for 100 keV electrons. To demonstrate the potential of imaging at 100 kV, the voltage of a standard, commercial 200 kV field-emission gun (FEG) microscope was reduced to 100 kV and a side-entry cryoholder was used. As high-efficiency, large-area cameras are not currently available for 100 keV electrons, a commercial hybrid pixel camera designed for X-ray detection was attached to the camera chamber and was used for low-dose data collection. Using this configuration, five single-particle specimens were imaged: hepatitis B virus capsid, bacterial 70S ribosome, catalase, DNA protection during starvation protein and haemoglobin, ranging in size from 4.5 MDa to 64 kDa with corresponding diameters from 320 to 72 Å. These five data sets were used to reconstruct 3D structures with resolutions between 8.4 and 3.4 Å. Based on this work, the practical advantages and current technological limitations to single-particle cryoEM at 100 keV are considered. These results are also discussed in the context of future microscope development towards the goal of rapid, simple and widely available structure determination of any purified biological specimen.

Copper-containing nitrite reductases (CuNiRs) are found in all three kingdoms of life and play a major role in the denitrification branch of the global nitro­gen cycle where nitrate is used in place of di­oxy­gen as an electron acceptor in respiratory energy metabolism. Several C- and N-terminal redox domain tethered CuNiRs have been identified and structurally characterized during the last decade. Our understanding of the role of tethered domains in these new classes of three-domain CuNiRs, where an extra cytochrome or cupredoxin domain is tethered to the catalytic two-domain CuNiRs, has remained limited. This is further compounded by a complete lack of substrate-bound structures for these tethered CuNiRs. There is still no substrate-bound structure for any of the as-isolated wild-type tethered enzymes. Here, structures of nitrite and product-bound states from a nitrite-soaked crystal of the N-terminal cupredoxin-tethered enzyme from the Hyphomicrobium denitrificans strain 1NES1 (Hd1NES1NiR) are provided. These, together with the as-isolated structure of the same species, provide clear evidence for the role of the N-terminal peptide bearing the conserved His27 in water-mediated anchoring of the substrate at the catalytic T2Cu site. Our data indicate a more complex role of tethering than the intuitive advantage for a partner-protein electron-transfer complex by narrowing the conformational search in such a combined system.