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The Time Response of Glass Resistive Plate Chambers to Heavily Ionizing Particles
2007
The HARP system of resistive plate chambers (RPCs) was designed to perform particle identification by the measurement of the difference in the time-of-flight of different particles. In previous papers an apparent discrepancy was shown between the response of the RPCs to minimum ionizing pions and heavily ionizing protons. Using the kinematics of elastic scattering off a hydrogen target a controlled beam of low momentum recoil protons was directed onto the chambers. With this method the trajectory and momentum, and hence the time-of-flight of the protons can be precisely predicted without need for a measurement of momentum of the protons. It is demonstrated that the measurement of the time-o…
Measurement of ultra-low heating rates of a single antiproton in a cryogenic Penning trap
2019
Physical review letters 122(4), 043201 (2019). doi:10.1103/PhysRevLett.122.043201
Experimental investigation of low-frequency pulsed Lorentz force influence on the motion of Galinstan melt
2016
Abstract The paper presents the results of the numerical and physical experiments, aimed at assessing the influence of pulsed force of electromagnetic field on the melt motion and the fluid velocities. The experiment was performed on the eutectic alloy Galinstan in the cylindrical volume, where an ultrasonic Doppler velocimeter was employed for velocity measurements under conditions of pulsed and steady EM field application. A numerical simulation of the melt flow, forced by the steady EM force, involved a 2D axisymmetric model. The k-e turbulence model was used to obtain the information about the melt velocities. The verification of the numerical model was carried out for the steady case. …
Frontispiece: A Novel High‐Pressure Tin Oxynitride Sn 2 N 2 O
2020
Chemistry - a European journal 26(10), 2187-2194 (2020). doi:10.1002/chem.202081063
Quantum Chemical Calculations Show that the Uranium Molecule U2 Has a Quintuple Bond.
2005
Covalent bonding is commonly described by Lewis's theory1, with an electron pair shared between two atoms constituting one full bond. Beginning with the valence bond description2 for the hydrogen molecule, quantum chemists have further explored the fundamental nature of the chemical bond for atoms throughout the periodic table, confirming that most molecules are indeed held together by one electron pair for each bond. But more complex binding may occur when large numbers of atomic orbitals can participate in bond formation. Such behaviour is common with transition metals. When involving heavy actinide elements, metal–metal bonds might prove particularly complicated. To date, evidence for ac…
Towards saturation of the electron-capture delayed fission probability: The new isotopes $^{240}Es$ and $^{236}Bk$
2016
Abstract The new neutron-deficient nuclei 240 Es and 236 Bk were synthesised at the gas-filled recoil separator RITU. They were identified by their radioactive decay chains starting from 240 Es produced in the fusion–evaporation reaction 209 Bi( 34 S,3n) 240 Es. Half-lives of 6 ( 2 ) s and 22 − 6 + 13 s were obtained for 240 Es and 236 Bk, respectively. Two groups of α particles with energies E α = 8.19 ( 3 ) MeV and 8.09 ( 3 ) MeV were unambiguously assigned to 240 Es. Electron-capture delayed fission branches with probabilities of 0.16 ( 6 ) and 0.04 ( 2 ) were measured for 240 Es and 236 Bk, respectively. These new data show a continuation of the exponential increase of ECDF probabilitie…
Ultra-fast direct growth of metallic micro- and nano-structures by focused ion beam irradiation
2019
An ultra-fast method to directly grow metallic micro- and nano-structures is introduced. It relies on a Focused Ion Beam (FIB) and a condensed layer of suitable precursor material formed on the substrate under cryogenic conditions. The technique implies cooling the substrate below the condensation temperature of the gaseous precursor material, subsequently irradiating with ions according to the wanted pattern, and posteriorly heating the substrate above the condensation temperature. Here, using W(CO)6 as the precursor material, a Ga+ FIB, and a substrate temperature of -100 °C, W-C metallic layers and nanowires with resolution down to 38 nm have been grown by Cryogenic Focused Ion Beam Indu…
Human exome and mouse embryonic expression data implicate ZFHX3, TRPS1, and CHD7 in human esophageal atresia
2020
Introduction Esophageal atresia with or without tracheoesophageal fistula (EA/TEF) occurs approximately 1 in 3.500 live births representing the most common malformation of the upper digestive tract. Only half a century ago, EA/TEF was fatal among affected newborns suggesting that the steady birth prevalence might in parts be due to mutational de novo events in genes involved in foregut development. Methods To identify mutational de novo events in EA/TEF patients, we surveyed the exome of 30 case-parent trios. Identified and confirmed de novo variants were prioritized using in silico prediction tools. To investigate the embryonic role of genes harboring prioritized de novo variants we perfor…
A vascular perspective on neuronal migration
2015
During CNS development and adult neurogenesis, immature neurons travel from the germinal zones towards their final destination using cellular substrates for their migration. Classically, radial glia and neuronal axons have been shown to act as physical scaffolds to support neuroblast locomotion in processes known as gliophilic and neurophilic migration, respectively (Hatten, 1999; Marin and Rubenstein, 2003; Rakic, 2003). In adulthood, long distance neuronal migration occurs in a glial-independent manner since radial glia cells differentiate into astrocytes after birth. A series of studies highlight a novel mode of neuronal migration that uses blood vessels as scaffolds, the so-called vasop…
Identification of the essential protein domains for Mib2 function during the development of the Drosophila larval musculature and adult flight muscles
2016
The proper differentiation and maintenance of myofibers is fundamental to a functional musculature. Disruption of numerous mostly structural factors leads to perturbations of these processes. Among the limited number of known regulatory factors for these processes is Mind bomb2 (Mib2), a muscle-associated E3 ubiquitin ligase, which was previously established to be required for maintaining the integrity of larval muscles. In this study, we have examined the mechanistic aspects of Mib2 function by performing a detailed functional dissection of the Mib2 protein. We show that the ankyrin repeats, in its entirety, and the hitherto uncharacterized Mib-specific domains (MIB), are important for the…