Mapping Glacier Forelands Based on UAV BVLOS Operation in Antarctica

The aim of this article is to show geomorphological mapping of remote Antarctic locations usingimagestakenbyafixed-wingunmannedaerialvehicle(UAV)duringtheBeyondVisualLineof Sight (BVLOS) operations. We mapped landform assemblages developed in forelands of Ecology Glacier (EGF), Sphinx Glacier (SGF) and Baranowski Glacier (BGF) in Antarctic Specially Protected Area No. 128 (ASPA 128) on King George Island (South Shetland Islands) and inferred about glacial dynamics. The orthophoto and digital elevation model allowed for geomorphological mapping of glacial forelands, including (i) glacial depositional landforms, (ii) fluvial and fluvioglacial landforms, (iii) littoral and lacustrine landforms, (iv) bodies of water, and (v) other. The largest area is occupied by ground moraine and glacial lagoons on EGF and BGF. The most profound features of EGF are the largelatero-frontalmoraineridgesfromLittleIceAgeandthefirsthalfofthe20thcentury. Largeareas of ground moraine, frequently fluted and marked with large recessional moraine ridges, dominate on SGF. A significant percentage of bedrock outcrops and end moraine complexes characterize BGF. The landform assemblages are typical for discontinuous fast ice flow of tidewater glaciers over a deformable bed. It is inferred that ice flow velocity decreased as a result of recession from the sea coast, resulting in a significant decrease in the length of ice cliffs and decrease in calving rate. Image acquisition during the fixed-wing UAV BVLOS operation proved to be a very robust technique in harsh polar conditions of King George Island

Prenatal diagnosis of Smith-Lemli-Opitz syndrome – case report

Abstract Smith-Lemli-Opitz syndrome (SLOS) is a hereditary, autosomal recessive abnormality of cholesterol metabolism, leading to malformations of multiple organs. It is probably one of the most frequent metabolic disorders but variable clinical presentation makes the diagnosis of the syndrome difficult. The authors of the following work present a case report of prenatal diagnosis of SLOS in fetus with malformations of multiple organs and negative family history

MetalionRNA: computational predictor of metal-binding sites in RNA structures

Motivation: Metal ions are essential for the folding of RNA molecules into stable tertiary structures and are often involved in the catalytic activity of ribozymes. However, the positions of metal ions in RNA 3D structures are difficult to determine experimentally. This motivated us to develop a computational predictor of metal ion sites for RNA structures

Noble Gas, Alkali and Alkaline Atoms Interacting with a Gold Surface

The attractive branch of the interaction potentials with the surface of gold have been computed for a large variety of atomic systems: the hydrogen atom, noble gases (He, Ne, Ar, Kr, Xe), alkali atoms (Li, Na, K, Rb, Cs) and alkaline atoms (Be, Mg, Ca, Sr, Ba). The results include highly accurate dynamic polarizabilities for the helium atom calculated using a variational method and explicitly correlated wavefunctions. For other atoms considered we used the data available in the literature. The interaction potentials include both the effects of retardation of the electromagnetic interactions and a realistic representation of the optical response function of gold (beyond the approximation of a perfect conductor). An explicit comparison of our result to the interaction between an atom and a perfect conductor is given. © 2010 World Scientific Publishing Company

Einstein-Hopf Drag, Doppler Shift of Thermal Radiation and Blackbody Drag: Three Perspectives on Quantum Friction

The thermal friction force acting on an atom moving relative to a thermal photon bath has recently been calculated on the basis of the fluctuation-dissipation theorem. The thermal fluctuations of the electromagnetic field give rise to a drag force on an atom provided one allows for dissipation of the field energy via spontaneous emission. The drag force exists if the atomic polarizability has a nonvanishing imaginary part. Here, we explore alternative derivations. The damping of the motion of a simple harmonic oscillator is described by radiative reaction theory (result of Einstein and Hopf), taking into account the known stochastic fluctuations of the electromagnetic field. Describing the excitations of the atom as an ensemble of damped harmonic oscillators, we identify the previously found expressions as generalizations of the Einstein-Hopf result. In addition, we present a simple explanation for blackbody friction in terms of a Doppler shift of the thermal radiation in the inertial frame of the moving atom: The atom absorbs blue-shifted photons from the front and radiates off energy in all directions, thereby losing energy. The original plus the two alternative derivations provide for additional confirmation of an intriguing quantum friction effect, and leave no doubt regarding its existence

Modern Experiments on Atom-Surface Casimir Physics

In this chapter we review past and current experimental approaches to measuring the long-range interaction between atoms and surfaces, the so-called Casimir-Polder force. These experiments demonstrate the importance of going beyond the perfect conductor approximation and stipulate the relevance of the Dzyaloshinskii-Lifshitz-Pitaevskii theory. We discuss recent generalizations of that theory, that include higher multipole polarizabilities, and present a list of additional effects, that may become important in future Casimir-Polder experiments. Among the latter, we see great potential for spectroscopic techniques, atom interferometry, and the manipulation of ultra-cold quantum matter (e.g. BEC) near surfaces. We address approaches based on quantum reflection and discuss the atomic beam spin-echo experiment as a particular example. Finally, some of the advantages of Casimir-Polder techniques in comparison to Casimir force measurements between macroscopic bodies are presented

BROADBAND CONCEPT OF ENERGY HARVESTING IN BEAM VIBRATING SYSTEMS FOR POWERING SENSORS

Recent demand for powering small sensors for wireless health monitoring triggered activities in the field of small size efficient energy harvesting devices. We examine energy harvesting in an aluminium beam with a piezoceramic patch subjected to kinematic harmonic excitation and impacts. Due to a mechanical stopper applied, inducing a hardening effect in the spring characteristic of the beam resonator, we observed a broader frequency range for the fairly large power output. Impact nonlinearities caused sensitivity to initial conditions and appearance of multiple solutions. The occurrence of resonant solution associated with impacts increased efficiency of the energy harvesting process