CHANG-ES XXIII: influence of a galactic wind in NGC 5775

Galaxie

Nearby galaxies in the LOFAR Two-metre Sky Survey: I. Insights into the non-linearity of the radio-SFR relation

Galaxie

HST Beobachtungen zur Physik von Grenzschichten zwischen heissem und kuehlem Gas Schlussbericht

Available from TIB Hannover: DtF QN1(93,38) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany); DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Bonn (Germany)DEGerman

Cosmic rays in astrospheres

Context: Cosmic rays passing through large astrospheres can be efficiently cooled inside these “cavities” in the interstellar medium. Moreover, the energy spectra of these energetic particles are already modulated in front of the astrospherical bow shocks. Aims: We study the cosmic ray flux in and around λ Cephei as an example for an astrosphere. The large-scale plasma flow is modeled hydrodynamically with radiative cooling. Methods: We study the cosmic ray flux in a stellar wind cavity using a transport model based on stochastic differential equations. The required parameters, most importantly, the elements of the diffusion tensor, are based on the heliospheric parameters. The magnetic field required for the diffusion coefficients is calculated kinematically. We discuss the transport in an astrospheric scenario with varying parameters for the transport coefficients. Results: We show that large stellar wind cavities can act as sinks for the Galactic cosmic ray flux and thus can give rise to small-scale anisotropies in the direction to the observer. Conclusions: Small-scale cosmic ray anisotropies can naturally be explained by the modulation of cosmic ray spectra in huge stellar wind cavitie

Controlled heterocoagulation of platelets and spheres

We report the controlled heterocoagulation of platelets and spheres, leading to the formation of colloidally stable, anisotropic hybrid particles. Anionically charged, nanosized polymer latex spherical particles were heterocoagulated on the surface of cationically charged hexagonal gibbsite platelets via the adsorption of a single layer of spheres onto both sides of the hexagonal platelets. The latex particles were annealed at a temperature above the Tg of the latex polymer, resulting in a thin polymer layer covering the gibbsite platelets. This heterocoagulation approach enabled the encapsulation of hydrophilic inorganic particles with polymer latexes and the formation of anisotropic hybrid particles

Controlled heterocoagulation of gibbsite platelets and latex spheres

We report the controlled heterocoagulation of gibbsite platelets and latex spheres, leading to the formation of colloidally stable, anisotropic hybrid particles. Anionically charged, nano-sized polymer latex spherical particles were heterocoagulated on the surface of cationically charged hexagonal gibbsite platelets via the adsorption of a single layer of spheres onto both sides of the hexagonal platelets. The latex particles were annealed at a temp. above the Tg of the latex polymer, resulting in a thin polymer layer covering the gibbsite platelets. This heterocoagulation approach enabled the encapsulation of hydrophilic inorg. particles with polymer latexes and the formation of anisotropic hybrid particles

Controlled heterocoagulation of platelets and spheres

We report the controlled heterocoagulation of platelets and spheres, leading to the formation of colloidally stable, anisotropic hybrid particles. Anionically charged, nanosized polymer latex spherical particles were heterocoagulated on the surface of cationically charged hexagonal gibbsite platelets via the adsorption of a single layer of spheres onto both sides of the hexagonal platelets. The latex particles were annealed at a temperature above the Tg of the latex polymer, resulting in a thin polymer layer covering the gibbsite platelets. This heterocoagulation approach enabled the encapsulation of hydrophilic inorganic particles with polymer latexes and the formation of anisotropic hybrid particles

Design and self-assembly of simple coat proteins for artificial viruses

Viruses are among the simplest biological systems and are highly effective vehicles for the delivery of genetic material into susceptible host cells1. Artificial viruses can be used as model systems for providing insights into natural viruses and can be considered a testing ground for developing artificial life. Moreover, they are used in biomedical and biotechnological applications, such as targeted delivery of nucleic acids for gene therapy1, 2 and as scaffolds in material science3, 4, 5. In a natural setting, survival of viruses requires that a significant fraction of the replicated genomes be completely protected by coat proteins. Complete protection of the genome is ensured by a highly cooperative supramolecular process between the coat proteins and the nucleic acids, which is based on reversible, weak and allosteric interactions only6, 7, 8, 9. However, incorporating this type of supramolecular cooperativity into artificial viruses remains challenging10, 11, 12, 13, 14, 15. Here, we report a rational design for a self-assembling minimal viral coat protein based on simple polypeptide domains. Our coat protein features precise control over the cooperativity of its self-assembly with single DNA molecules to finally form rod-shaped virus-like particles. We confirm the validity of our design principles by showing that the kinetics of self-assembly of our virus-like particles follows a previous model developed for tobacco mosaic virus9. We show that our virus-like particles protect DNA against enzymatic degradation and transfect cells with considerable efficiency, making them promising delivery vehicles