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Intolerance Row: Director Vikram Sampath withdraws participation from Bangalore Lit Fest

In a statement released on his Facebook page, Sampath has taken the decision to step away from the upcoming edition of the festival altogether.




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Suresh Raina, Irfan Pathan want BCCI to let Indian cricketers participate in foreign T20 leagues

During the session, Raina also said that there was no communication between him and the then chairman of selectors MSK Prasad regarding his selection in the national team.




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Forty years of electrical progress: a reprint of the articles which appeared in the 2000th number of "The Electrician", September 15th, 1916.

Archives, Room Use Only - TK57.F67 1916




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Signal tactics: assimilated to the tactics of artillery, cavalry and infantry, prepared for the use of officers and enlisted men of the military and naval forces of the United States and adapted for the use of the National Guards and military academies /

Archives, Room Use Only - UG573.R44 1880




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[Collection of articles on telegraphy].

Archives, Room Use Only - TK5269.C65 1873




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Selected articles on government ownership of the telegraph / compiled by Edith M. Phelps

Archives, Room Use Only - HE7781.P54 1912




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Wireless transmission of photographs / by Marcus J. Martin

Archives, Room Use Only - TK6600.M37 1916




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Mit Spulen, Draht und Morsetaste / Martin Selber ; Zeichnungen von Editha Rosenthal und Heinz-Karl Bogdanski

Archives, Room Use Only - TK5265.S45 1953




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Ex ordinis philosophorum mandato renuntiantur philosophiae doctores: et artium liberalium magistri rectore magnifico Ioanne Adolpho Overbeck ... decano Gustavo Henrico Wiedemann ... procancellario Ludovico Lange ... inde a die primo mensis Novembris a. MD

Archives, Room Use Only - QC761.W54 1876




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[Collection of articles on telegraphy].

Archives, Room Use Only - TK5269.C65 1869b




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Recent wonders in electricity, electric lighting, magnetism, telegraphy, telephony, etc., etc. / including articles by Dr. Siemens, F.R.S. Count du Moncel and Prof. Thomson [sic] ; edited by Henry Greer

Archives, Room Use Only - TK148.G74 1883




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Artificial intelligence can serve as backup to radiologists' eyes




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Suresh Raina, Irfan Pathan want BCCI to allow Indian players to participate in foreign T20 leagues




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Gwyneth Paltrow jokes Elon Musk, Grimes 'beat' her and Chris Martin for 'most controversial baby name'




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Pawan Kalyan to political parties: Don't protest over Vizag amid pandemic




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NDMA issues guidelines for restarting industrial activities to avoid Vizag-type tragedy

In the wake of the gas leak at a factory in Visakhapatnam, the National Disaster Management Authority (NDMA) has issued detailed guidelines for restarting industries after the lockdown and the precautions to be taken for the safety of the plants as well as the workers.




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Suresh Raina, Irfan Pathan want BCCI to let Indian cricketers participate i...

Suresh Raina, Irfan Pathan want BCCI to let Indian cricketers participate i...




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Starting Monday: 6-day mantra to exit lockdown

For almost 50 days of the Covid-imposed lockdown, our factories have remained shut, academic schedules upset, malls and theatres locked and infrastructure work stalled. The virus has stopped us in our tracks. But not forever.




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Bal Bharti Academy NGO launches social platform to fight against COVID-19




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Vizag tragedy aftermath: NDMA issues guidelines for restarting industries

The NDMA guidelines said while restarting a unit, the first week should be considered as the trial or test run period after ensuring all safety protocols




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Watch Kartik Aaryan's hilarious performance

Kartik Aaryan has been quite active on social media in raising awareness about the pandemic and at the same time requesting all his fans to stay indoors. Not only that but the talented star has also come out in support of the government and contributed to the PM's CARES Fund as well.




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Kartik wants to know his mother’s secret

Kartik Aaryan says mothers are everything, its an emotion in itself. The 'Love Aaj Kal' star who shares a close bond with his mum Mala Tiwari wants to learn the magic of multitasking from her. On the occasion of Mother's Day, Kartik exclusively spoke to ETimes about the things he has imbibed from his maa.




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B'luru: Partitions to shield cabbies, passengers

To protect both cabbies and passengers during the Covid-19 pandemic, some taxi operators in the city have installed plastic sheets in their vehicles to separate the driver and rear seats.




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'Patronised' Partick hit out as Scottish football row rumbles on

'Patronised' Partick hit out as Scottish football row rumbles on




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Starting Monday: Six-day mantra to exit lockdown

Starting Monday: Six-day mantra to exit lockdown




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B'luru: Partitions to shield cabbies, passengers

B'luru: Partitions to shield cabbies, passengers




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Tattoo artist held with husband for snatching

Tattoo artist held with husband for snatching




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Indian artist sketches Trump's portrait to gift him




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Punjab to lift partial lockdown only for farmers




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DNA Exclusive: Arti Singh remembers how her first letter to mother brought them closer

Arti Singh remembered her first letter to mother on the occasion of Mothers' Day




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Donald Trump congratulates UFC for restarting sports




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Coherent Bragg imaging of 60 nm Au nanoparticles under electrochemical control at the NanoMAX beamline

Nanoparticles are essential electrocatalysts in chemical production, water treatment and energy conversion, but engineering efficient and specific catalysts requires understanding complex structure–reactivity relations. Recent experiments have shown that Bragg coherent diffraction imaging might be a powerful tool in this regard. The technique provides three-dimensional lattice strain fields from which surface reactivity maps can be inferred. However, all experiments published so far have investigated particles an order of magnitude larger than those used in practical applications. Studying smaller particles quickly becomes demanding as the diffracted intensity falls. Here, in situ nanodiffraction data from 60 nm Au nanoparticles under electrochemical control collected at the hard X-ray nanoprobe beamline of MAX IV, NanoMAX, are presented. Two-dimensional image reconstructions of these particles are produced, and it is estimated that NanoMAX, which is now open for general users, has the requisites for three-dimensional imaging of particles of a size relevant for catalytic applications. This represents the first demonstration of coherent X-ray diffraction experiments performed at a diffraction-limited storage ring, and illustrates the importance of these new sources for experiments where coherence properties become crucial.




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Diffuse scattering and partial disorder in complex structures

This review discusses the state of the field of single-crystal diffuse scattering (SCDS), including detectors, data collection and the modelling techniques. High quality, three-dimensional volumes of SCDS data can now be collected at synchrotron light sources, allowing increasingly detailed and quantitative analyses to be undertaken.






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A comparative study of single-particle cryo-EM with liquid-nitrogen and liquid-helium cooling

Radiation damage is the most fundamental limitation for achieving high resolution in electron cryo-microscopy (cryo-EM) of biological samples. The effects of radiation damage are reduced by liquid-helium cooling, although the use of liquid helium is more challenging than that of liquid nitrogen. To date, the benefits of liquid-nitrogen and liquid-helium cooling for single-particle cryo-EM have not been compared quantitatively. With recent technical and computational advances in cryo-EM image recording and processing, such a comparison now seems timely. This study aims to evaluate the relative merits of liquid-helium cooling in present-day single-particle analysis, taking advantage of direct electron detectors. Two data sets for recombinant mouse heavy-chain apoferritin cooled with liquid-nitrogen or liquid-helium to 85 or 17 K were collected, processed and compared. No improvement in terms of resolution or Coulomb potential map quality was found for liquid-helium cooling. Interestingly, beam-induced motion was found to be significantly higher with liquid-helium cooling, especially within the most valuable first few frames of an exposure, thus counteracting any potential benefit of better cryoprotection that liquid-helium cooling may offer for single-particle cryo-EM.




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Refinement for single-nanoparticle structure determination from low-quality single-shot coherent diffraction data

With the emergence of X-ray free-electron lasers, it is possible to investigate the structure of nanoscale samples by employing coherent diffractive imaging in the X-ray spectral regime. In this work, we developed a refinement method for structure reconstruction applicable to low-quality coherent diffraction data. The method is based on the gradient search method and considers the missing region of a diffraction pattern and the small number of detected photons. We introduced an initial estimate of the structure in the method to improve the convergence. The present method is applied to an experimental diffraction pattern of an Xe cluster obtained in an X-ray scattering experiment at the SPring-8 Angstrom Compact free-electron LAser (SACLA) facility. It is found that the electron density is successfully reconstructed from the diffraction pattern with a large missing region, with a good initial estimate of the structure. The diffraction pattern calculated from the reconstructed electron density reproduced the observed diffraction pattern well, including the characteristic intensity modulation in each ring. Our refinement method enables structure reconstruction from diffraction patterns under difficulties such as missing areas and low diffraction intensity, and it is potentially applicable to the structure determination of samples that have low scattering power.




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Characterizing crystalline defects in single nanoparticles from angular correlations of single-shot diffracted X-rays

Characterizing and controlling the uniformity of nanoparticles is crucial for their application in science and technology because crystalline defects in the nanoparticles strongly affect their unique properties. Recently, ultra-short and ultra-bright X-ray pulses provided by X-ray free-electron lasers (XFELs) opened up the possibility of structure determination of nanometre-scale matter with Å spatial resolution. However, it is often difficult to reconstruct the 3D structural information from single-shot X-ray diffraction patterns owing to the random orientation of the particles. This report proposes an analysis approach for characterizing defects in nanoparticles using wide-angle X-ray scattering (WAXS) data from free-flying single nanoparticles. The analysis method is based on the concept of correlated X-ray scattering, in which correlations of scattered X-ray are used to recover detailed structural information. WAXS experiments of xenon nanoparticles, or clusters, were conducted at an XFEL facility in Japan by using the SPring-8 Ångstrom compact free-electron laser (SACLA). Bragg spots in the recorded single-shot X-ray diffraction patterns showed clear angular correlations, which offered significant structural information on the nanoparticles. The experimental angular correlations were reproduced by numerical simulation in which kinematical theory of diffraction was combined with geometric calculations. We also explain the diffuse scattering intensity as being due to the stacking faults in the xenon clusters.





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LAT1 (SLC7A5) and CD98hc (SLC3A2) complex dynamics revealed by single-particle cryo-EM

Solute carriers are a large class of transporters that play key roles in normal and disease physiology. Among the solute carriers, heteromeric amino-acid transporters (HATs) are unique in their quaternary structure. LAT1–CD98hc, a HAT, transports essential amino acids and drugs across the blood–brain barrier and into cancer cells. It is therefore an important target both biologically and therapeutically. During the course of this work, cryo-EM structures of LAT1–CD98hc in the inward-facing conformation and in either the substrate-bound or apo states were reported to 3.3–3.5 Å resolution [Yan et al. (2019), Nature (London), 568, 127–130]. Here, these structures are analyzed together with our lower resolution cryo-EM structure, and multibody 3D auto-refinement against single-particle cryo-EM data was used to characterize the dynamics of the interaction of CD98hc and LAT1. It is shown that the CD98hc ectodomain and the LAT1 extracellular surface share no substantial interface. This allows the CD98hc ectodomain to have a high degree of movement within the extracellular space. The functional implications of these aspects are discussed together with the structure determination.




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Flexible workflows for on-the-fly electron-microscopy single-particle image processing using Scipion

Electron microscopy of macromolecular structures is an approach that is in increasing demand in the field of structural biology. The automation of image acquisition has greatly increased the potential throughput of electron microscopy. Here, the focus is on the possibilities in Scipion to implement flexible and robust image-processing workflows that allow the electron-microscope operator and the user to monitor the quality of image acquisition, assessing very simple acquisition measures or obtaining a first estimate of the initial volume, or the data resolution and heterogeneity, without any need for programming skills. These workflows can implement intelligent automatic decisions and they can warn the user of possible acquisition failures. These concepts are illustrated by analysis of the well known 2.2 Å resolution β-galactosidase data set.




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Identifying dynamic, partially occupied residues using anomalous scattering

Although often presented as taking single `snapshots' of the conformation of a protein, X-ray crystallography provides an averaged structure over time and space within the crystal. The important but difficult task of characterizing structural ensembles in crystals is typically limited to small conformational changes, such as multiple side-chain conformations. A crystallographic method was recently introduced that utilizes residual electron and anomalous density (READ) to characterize structural ensembles encompassing large-scale structural changes. Key to this method is an ability to accurately measure anomalous signals and distinguish them from noise or other anomalous scatterers. This report presents an optimized data-collection and analysis strategy for partially occupied iodine anomalous signals. Using the long-wavelength-optimized beamline I23 at Diamond Light Source, the ability to accurately distinguish the positions of anomalous scatterers with occupancies as low as ∼12% is demonstrated. The number and positions of these anomalous scatterers are consistent with previous biophysical, kinetic and structural data that suggest that the protein Im7 binds to the chaperone Spy in multiple partially occupied conformations. Finally, READ selections demonstrate that re-measured data using the new protocols are consistent with the previously characterized structural ensemble of the chaperone Spy with its client Im7. This study shows that a long-wavelength beamline results in easily validated anomalous signals that are strong enough to be used to detect and characterize highly disordered sections of crystal structures.




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Open-access and free articles in Acta Crystallographica Section D: Biological Crystallography




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From space group to space groupoid: the partial symmetry of low-temperature E-vanillyl oxime

The phase transition of E-vanillyl oxime {1-[(E)-(hydroxyimino)methyl]-4-hydroxy-3-methoxybenzene, C8H9NO3} has been analysed by single-crystal and powder X-ray diffraction. The high-temperature (HT) phase (P21/a, Z' = 1) transforms into the low-temperature (LT) phase (threefold superstructure, Poverline{1}, Z' = 6) at ca 190 K. The point operations lost on cooling, {m[010], 2[010]}, are retained as twin operations and constitute the twin law. The screw rotations and glide reflections are retained in the LT phase as partial operations acting on a subset of Euclidean space {b E}^3. The full symmetry of the LT phase, including partial operations, is described by a disconnected space groupoid which is built of three connected components.




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Laser-induced metastable mixed phase of AuNi nanoparticles: a coherent X-ray diffraction imaging study

The laser annealing process for AuNi nanoparticles has been visualized using coherent X-ray diffraction imaging (CXDI). AuNi bimetallic alloy nanoparticles, originally phase separated due to the miscibility gap, transform to metastable mixed alloy particles with rounded surface as they are irradiated by laser pulses. A three-dimensional CXDI shows that the internal part of the AuNi particles is in the mixed phase with preferred compositions at ∼29 at% of Au and ∼90 at% of Au.




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Quantifying redox heterogeneity in single-crystalline LiCoO2 cathode particles

Active cathode particles are fundamental architectural units for the composite electrode of Li-ion batteries. The microstructure of the particles has a profound impact on their behavior and, consequently, on the cell-level electrochemical performance. LiCoO2 (LCO, a dominant cathode material) is often in the form of well-shaped particles, a few micrometres in size, with good crystallinity. In contrast to secondary particles (an agglomeration of many fine primary grains), which are the other common form of battery particles populated with structural and chemical defects, it is often anticipated that good particle crystallinity leads to superior mechanical robustness and suppressed charge heterogeneity. Yet, sub-particle level charge inhomogeneity in LCO particles has been widely reported in the literature, posing a frontier challenge in this field. Herein, this topic is revisited and it is demonstrated that X-ray absorption spectra on single-crystalline particles with highly anisotropic lattice structures are sensitive to the polarization configuration of the incident X-rays, causing some degree of ambiguity in analyzing the local spectroscopic fingerprint. To tackle this issue, a methodology is developed that extracts the white-line peak energy in the X-ray absorption near-edge structure spectra as a key data attribute for representing the local state of charge in the LCO crystal. This method demonstrates significantly improved accuracy and reveals the mesoscale chemical complexity in LCO particles with better fidelity. In addition to the implications on the importance of particle engineering for LCO cathodes, the method developed herein also has significant impact on spectro-microscopic studies of single-crystalline materials at synchrotron facilities, which is broadly applicable to a wide range of scientific disciplines well beyond battery research.




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Solid/liquid-interface-dependent synthesis and immobilization of copper-based particles nucleated by X-ray-radiolysis-induced photochemical reaction




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Forthcoming article in Journal of Synchrotron Radiation




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Comment on the article The nanodiffraction problem




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Response to Zbigniew Kaszkur's comment on the article The nanodiffraction problem