Spherical Maps Of Euclidean Spaces

We classify the maps f: Rp → Rn suchthat ¦fat -fb¦ = ¦fbt -fc¦ whenever ¦a?b¦= ¦b? c¦.     

Constructing Large 2D Lattices Out of DNA-Tiles

The predictable nature of deoxyribonucleic acid (DNA) interactions enables assembly of DNA into almost any arbitrary shape with programmable features of nanometer precision. The recent progress of DNA nanotechnology has allowed production of an even wider gamut of possible shapes with high-yield and error-free assembly processes. Most of these structures are, however, limited in size to a nanometer scale. To overcome this limitation, a plethora of studies has been carried out to form larger structures using DNA assemblies as building blocks or tiles. Therefore, DNA tiles have become one of the most widely used building blocks for engineering large, intricate structures with nanometer precision. To create even larger assemblies with highly organized patterns, scientists have developed a variety of structural design principles and assembly methods. This review first summarizes currently available DNA tile toolboxes and the basic principles of lattice formation and hierarchical self-assembly using DNA tiles. Special emphasis is given to the forces involved in the assembly process in liquid-liquid and at solid-liquid interfaces, and how to master them to reach the optimum balance between the involved interactions for successful self-assembly. In addition, we focus on the recent approaches that have shown great potential for the controlled immobilization and positioning of DNA nanostructures on different surfaces. The ability to position DNA objects in a controllable manner on technologically relevant surfaces is one step forward towards the integration of DNA-based materials into nanoelectronic and sensor devices.     

Investigating isomerization reactions in solid state by using simultaneous high overtone pumping and Raman detection

Formation of the unstable cis-formic acid in solid argon matrix is induced by direct excitation of the 6<--0 transition of the nu(OH) vibration of the trans-formic acid. The experiment utilizes strongly focused laser beam that produces relatively high isomerization rate despite the low cross section of the absorption. Raman spectroscopy in a backscattering geometry is used for detection of the reactants and the products. This experimental arrangement allow us to use the same laser source for simultaneous pumping and Raman excitation, and it also guarantees that the excited and probed volumes overlap. The presented method has a high potential for solid state investigations of chemical reactions on the ground electronic state.     

Industrial impulse noise: Crest factor as an additional parameter in exposure measurements

A procedure to measure industrial impulse noise was developed that provides information on both the equivalent noise level and impulsiveness. Impulsiveness of the signal was defined as the difference between the A-weighted peak level and the root-mean-square level. This difference, also known as a crest factor, varies in time, so the cumulative distribution function was used to describe the probability to achieve a certain value of impulsiveness. A telemetric sampling system carried by the worker was used to take measurements at a shipyard. The sample duration of 10 minutes was considered sufficient to cover welders', platers', and grinders' different work phases. The total number of 10 minute samples was 123. The welders were exposed to the most impulsive noise, whereas the grinders were exposed to the highest equivalent noise level. The present paper describing a procedure to measure industrial impulse noise comprises part of a follow-up study on the effects of noise on hearing.     

Singular Indefinite Sturm-Liouville Operators with a Spectral Gap

Singular Sturm-Liouville operators with the indefinite weight sgn(·) and a symmetric potential which has a positive limit at ∞ have a gap in the essential spectrum. Under an additional condition it is shown that in this gap are no eigenvalues. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Linear water-wave problem in a pond with a shallow beach

We consider the linear water-wave problem in a bounded water-basin with a shallow beach. In spite of the boundedness of the domain, the spectrum of the problem may have a continuous component, if the beach of the basin has a cuspidal form. Following the approach and methods of an earlier paper by S.A.Nazarov and the second named author, we improve the results of the citation by determining the spectrum in an open borderline case under weaker geometric assumptions.     

Mechanisms of Carbon Sequestration in Highly Organic Ecosystems – Importance of Chemical Ecology

Organic matter decomposition plays a major role in the cycling of carbon (C) and nutrients in terrestrial ecosystems across the globe. Climate change accelerates the decomposition rate to potentially increase the release of greenhouse gases and further enhance global warming in the future. However, fractions of organic matter vary in turnover times and parts are stabilized in soils for longer time periods (C sequestration). Overall, a better understanding of the mechanisms underlying C sequestration is needed for the development of effective mitigation policies to reduce land-based production of greenhouse gases. Known mechanisms of C sequestration include the recalcitrance of C input, interactions with soil minerals, aggregate formation, as well as its regulation via abiotic factors. In this Minireview, we discuss the mechanisms behind C sequestration including the recently emerging significance of biochemical interactions between organic matter inputs that lead to C stabilization.     

Ad Hoc LTE Method for Resilient Smart Grid Communications

Wireless Personal Communications - LTE network is a good choice for delivering smart grid demand response (DR) traffic. However, LTE connectivity is not pervasively available due to smart meter...