Search results for "genetics [Transcriptome]"

Simultaneous imaging of the surface and the submembraneous cytoskeleton in living cells by tapping mode atomic force microscopy

1997

Contact and tapping mode atomic force microscopy have been used to visualize the surface of cultured CV-1 kidney cells in aqueous medium. The height images obtained from living cells were comparable when using contact and tapping modes. In contrast, the corresponding, and simultaneously acquired, deflection images differed markedly. Whereas, as expected, deflection images enhanced the surface features in the contact mode, they revealed the presence of a filamentous network when using the tapping mode. This network became disorganized upon addition of cytochalasin, which strongly suggests that it corresponded to the submembraneous cytoskeleton. Examination of fixed cells further supported th…

Distorted f.c.c. arrangement of gold nanoclusters: a model of spherical particles with microstrains and stacking faults

2008

The structures of two samples of gold nanoclusters supported on silica were studied by X-ray powder diffraction (XRD) and X-ray absorption spectroscopy. The data relative to both techniques were analysed by an approach involving simulation based on structural models and fitting. The XRD model concerned a distorted f.c.c. (face-centred cubic) arrangement, with microstrains and parallel stacking faults in approximately spherical particles; as an alternative possibility, a linear combination of ordered f.c.c. and noncrystalline (decahedral and icosahedral) particles was also taken into account. Both approaches gave calculated patterns closely resembling the experimental data. X-ray absorption …

Nanoscale assembly processes revealed in the nacroprismatic transition zone of Pinna nobilis mollusc shells

2015

Intricate biomineralization processes in molluscs engineer hierarchical structures with meso-, nano-, and atomic architectures that give the final composite material exceptional mechanical strength and optical iridescence on the macroscale. This multiscale biological assembly inspires new synthetic routes to complex materials. Our investigation of the prism-nacre interface reveals nanoscale details governing the onset of nacre formation using high-resolution scanning transmission electron microscopy. A wedge polishing technique provides unprecedented, large-area specimens required to span the entire interface. Within this region, we find a transition from nanofibrillar aggregation to irregu…

Polycyclic aromatic chains on metals and insulating layers by repetitive [3+2] cycloadditions

2020

The vast potential of organic materials for electronic, optoelectronic and spintronic devices entails substantial interest in the fabrication of π-conjugated systems with tailored functionality directly at insulating interfaces. On-surface fabrication of such materials on non-metal surfaces remains to be demonstrated with high yield and selectivity. Here we present the synthesis of polyaromatic chains on metallic substrates, insulating layers, and in the solid state. Scanning probe microscopy shows the formation of azaullazine repeating units on Au(111), Ag(111), and h-BN/Cu(111), stemming from intermolecular homo-coupling via cycloaddition reactions of CN-substituted polycyclic aromatic az…

2016

AbstractMaterials that demonstrate long-range magnetic order are synonymous with information storage and the electronics industry, with the phenomenon commonly associated with metals, metal alloys or metal oxides and sulfides. A lesser known family of magnetically ordered complexes are the monometallic compounds of highly anisotropic d-block transition metals; the ‘transformation’ from isolated zero-dimensional molecule to ordered, spin-canted, three-dimensional lattice being the result of through-space interactions arising from the combination of large magnetic anisotropy and spin-delocalization from metal to ligand which induces important intermolecular contacts. Here we report the effect…

THERMODYNAMICAL EXPLANATION OF LARGE PERIODS IN HIGH POLYMER CRYSTALS AND DRAWN FIBERS

1961

Local electronic structure rearrangements and strong anharmonicity in YH3 under pressures up to 180 GPa

2021

The authors acknowledge the ESRF program committee (Grenoble, France) for the opportunity to perform XAFS and XRD measurements. We are grateful to Prof. Dr Marek Tkacz from the Institute of Physical Chemistry, PAS Kasprzaka 44/52, 01-224 Warsaw, Poland, for high quality YH3 samples and to Dr. José A. Flores-Livas for a fruitful discussion. A.P.M. and A.A.I. acknowledge the Russian Foundation for the Basic Research (grant No 18-02-40001_mega) for financial support. J.P., A.K., and I.P. would like to thank the support of the Latvian Council of Science project No. lzp-2018/2-0353. ISSP UL acknowledge the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-20l 6-2017-TeamingPh…

Orientation of non-spherical protonated water clusters revealed by infrared absorption dichroism

2018

Infrared continuum bands that extend over a broad frequency range are a key spectral signature of protonated water clusters. They are observed for many membrane proteins that contain internal water molecules, but their microscopic mechanism has remained unclear. Here we compute infrared spectra for protonated and unprotonated water chains, discs, and droplets from ab initio molecular dynamics simulations. The continuum bands of the protonated clusters exhibit significant anisotropy for chains and discs, with increased absorption along the direction of maximal cluster extension. We show that the continuum band arises from the nuclei motion near the excess charge, with a long-ranged amplifica…

Direct imaging of delayed magneto-dynamic modes induced by surface acoustic waves.

2017

The magnetoelastic effect—the change of magnetic properties caused by the elastic deformation of a magnetic material—has been proposed as an alternative approach to magnetic fields for the low-power control of magnetization states of nanoelements since it avoids charge currents, which entail ohmic losses. Here, we have studied the effect of dynamic strain accompanying a surface acoustic wave on magnetic nanostructures in thermal equilibrium. We have developed an experimental technique based on stroboscopic X-ray microscopy that provides a pathway to the quantitative study of strain waves and magnetization at the nanoscale. We have simultaneously imaged the evolution of both strain and magne…

Magnon detection using a ferroic collinear multilayer spin valve

2018

Information transport and processing by pure magnonic spin currents in insulators is a promising alternative to conventional charge-current-driven spintronic devices. The absence of Joule heating and reduced spin wave damping in insulating ferromagnets have been suggested for implementing efficient logic devices. After the successful demonstration of a majority gate based on the superposition of spin waves, further components are required to perform complex logic operations. Here, we report on magnetization orientation-dependent spin current detection signals in collinear magnetic multilayers inspired by the functionality of a conventional spin valve. In Y3Fe5O12|CoO|Co, we find that the de…