The influence of spatially modulated high gradient magnetic fields on cellular functions of human THP-1 leukemia cells has been studied. We demonstrate that arrays of high-gradient micrometer-sized magnets induce i) cell swelling, ii) prolonged increased ROS production, iii) inhibit cell proliferation, and iv) elicit apoptosis of THP-1 monocytic leukemia cells in the absence of chemical or biological agents. Mathematical modeling indicates that mechanical stress exerted...
Polycyclic aromatic hydrocarbons appear among the most abundant observed species in interstellar space and are key molecules to understanding the prebiotic roots of life. However, their existence and abundance in space remain a puzzle. We have shown that aromatic species can be efficiently formed on the graphitized surface of the abundant silicon carbide stardust on exposure to atomic hydrogen under pressure and temperature conditions analogous to those of the...
An improved measurement of the mass of the Higgs boson is derived from a combined fit to the reconstructed invariant mass spectra of the decay channels H→γγ and H→ZZ*→4ℓ. The analysis uses the pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at center-of-mass energies of 7 TeV and 8 TeV, corresponding to an integrated luminosity of 25 fb−1. The measured value of the Higgs boson mass is mH = ...
Characteristic frequencies of nanoscale polar fluctuations have been resolved by means of neutron diffuse scattering measurements on a Sr0,61Ba0,39Nb2O6 single crystal in the MHz-GHz frequency region. Comparison with dielectric measurements proved that these polar fluctuations are a source of giant dielectric response, whose temperature-frequency dependence is specific for a significant group of substances...
High average power diode pumped solid state lasers development stimulates effort to increase its efficiency and lower energy losses. Thermal losses in an active media of a laser lead, for example, to degradation of the laser beam profile, and limit achievable average output power and laser efficiency. Nonlinear phonon relaxation in an Yb:YAG single crystal, which is usually pumped near the wavelength of 940 nm, causes a nonlinear increase in temperature of...
State-of-the-art laser systems are able to generate ionising radiation of significantly high energies by focusing ultra-short and intense pulses onto targets. Thus, measures ensuring the radiation protection of both working personnel and the general public are required. However, commercially available dosemeters are primarily designed for measurement in continuous fields. Therefore, it is important to explore their response to very short pulses. In this study, the...
The surface detector array of the Pierre Auger Observatory provides information about the longitudinal development of the muonic component of extensive air showers. Using the timing information from the flash analog-to-digital converter traces of surface detectors far from the shower core, it is possible to reconstruct a muon production depth distribution. We characterize the goodness of this reconstruction for zenith angles around 60 deg. and different energies of...
Crystallographic analysis showed that {1 0 1 2} twinning is the main deformation mechanism during compression. Twin-free microstructure, stress–strain curve, measured microtextures and macroscopic sample dimensions proved that reversible motion of twin boundaries („de-twinning“) occurs during subsequent compression along the normal direction which is more favourable than nucleation of new {1 0 1 2} twins during this compression thus profiling...
Measurement of top quark pair production charge asymmetry serves as an important test of Standard Model of particle physics (SM). The charge asymmetry observed in recent measurements from Tevatron was greater than predictions with regard to SM. This paper presents a measurement of the top quark pair production charge asymmetry AC using proton-proton collisions at a centre-of-mass energy √s = 7 TeV collected by the ATLAS detector at the...
Ferromagnets are able to store digital information as "0" and "1" using different orientation of magnetic moments that could be pictured as small compasses (image a). This principle works in a broad variety of memory devices from kilobyte magnetic cards to terabyte hard disks. Ferromagnetic memory devices can't be placed near to another magnets or devices producing strong magnetict field – magnetic moments in memory would be reoriented resulting in loss of...
Magnetization and sound propagation studied on a high-quality single crystal of ferrimagnetic compound TmFe5Al7 in high magnetic fields up to 60 Tesla reveal very unusual combination of spontaneous and field-induced transitions as the Tm provides an uniaxial magnetic anisotropy, whereas Fe favors an easy-plane anisotropy. This competition results in a omplex scenario of magnetic order including in-plane antiferromagnetic phase...
Optical gold elements coated with diamond layers with flat, nanocolumnar, and nanoporous morphologies. Fabricated diamond coated optical elements were successfully used for the grazing angle reflectance FTIR characterization of fetal bovin serum (FBS) proteins adsorbed on the O-terminated diamond surface. In spite of the different processing and structuring, all types of diamond layers showed good stability, uniformity, and optical properties, including good reflectivity...
The influence of laser frequency on laser-driven ion acceleration is investigated by means of twodimensional particle-in-cell simulations. When ultrashort intense laser pulse at higher harmonic frequency irradiates a thin solid foil, the target may become relativistically transparent for significantly lower laser pulse intensity compared with irradiation at fundamental laser frequency. The relativistically induced transparency results in an enhanced heating of hot...
In this paper, new steps toward a etter understanding and utilization of high-pressure high-temperature nanodiamonds (NDs) containing nitrogen-vacancy (NV) centers have been taken. NV–-related long-term luminescence of oxygenated particles increased in comparison to plasma hydrogenated NDs’ NV– luminescence. The optically detected NV– electron spin resonance process can be also significantly affected by ND termination. For H-terminated ND particles the NV– to NV0...
We developed an original fully relativistic ab initio theory of anomalous Hall effect for disordered ferromagnetic alloys with simple and complex lattice structure. The theory was applied to elementary ferromagnets (Fe, Co, Ni), their alloys (NiFe, FeSi), to partially ordered FePt alloys and to selected Heusler alloys in a good agreement with experiment. Anomalous Hall effect in Heusler alloys is important for prospective applications in spintronics.
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