A shortcut to high-affinity Ga-68 and Cu-64 radiopharmaceuticals: one-pot click chemistry trimerisation on the TRAP platform

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BVR photometry of the resolved dwarf galaxy Ho IX

We present BVR CCD photometry down to limiting magnitude B=23.5 mag for 232 starlike objects and 11 diffuse objects in a 5.4' x 5.4' field of Ho IX. The galaxy is a gas-rich irregular dwarf galaxy possibly very close to M 81, which makes it especially interesting in the context of the evolution of satellite galaxies and the accretion of dwarf galaxies. Investigations of Ho IX were hampered by relatively large contradictions in the magnitude scale between earlier studies. With our new photometry we resolved these discrepancies. The color magnitude diagram (CMD) of Ho IX is fairly typical of a star-forming dwarf irregular, consistent with earlier results. Distance estimates from our new CMD are consistent with Ho IX being very close to M 81 and therefore being a definite member of the M 81 group, apparently in very close physical proximity to M 81.Comment: 9 pages, 8 figures, uses aa.cls, A&A in pres

Synthesis of Symmetrical Tetrameric Conjugates of the Radiolanthanide Chelator DOTPI for Application in Endoradiotherapy by Means of Click Chemistry

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The Science of Sungrazers, Sunskirters, and Other Near-Sun Comets

This review addresses our current understanding of comets that venture close to the Sun, and are hence exposed to much more extreme conditions than comets that are typically studied from Earth. The extreme solar heating and plasma environments that these objects encounter change many aspects of their behaviour, thus yielding valuable information on both the comets themselves that complements other data we have on primitive solar system bodies, as well as on the near-solar environment which they traverse. We propose clear definitions for these comets: We use the term near-Sun comets to encompass all objects that pass sunward of the perihelion distance of planet Mercury (0.307 AU). Sunskirters are defined as objects that pass within 33 solar radii of the Sun’s centre, equal to half of Mercury’s perihelion distance, and the commonly-used phrase sungrazers to be objects that reach perihelion within 3.45 solar radii, i.e. the fluid Roche limit. Finally, comets with orbits that intersect the solar photosphere are termed sundivers. We summarize past studies of these objects, as well as the instruments and facilities used to study them, including space-based platforms that have led to a recent revolution in the quantity and quality of relevant observations. Relevant comet populations are described, including the Kreutz, Marsden, Kracht, and Meyer groups, near-Sun asteroids, and a brief discussion of their origins. The importance of light curves and the clues they provide on cometary composition are emphasized, together with what information has been gleaned about nucleus parameters, including the sizes and masses of objects and their families, and their tensile strengths. The physical processes occurring at these objects are considered in some detail, including the disruption of nuclei, sublimation, and ionisation, and we consider the mass, momentum, and energy loss of comets in the corona and those that venture to lower altitudes. The different components of comae and tails are described, including dust, neutral and ionised gases, their chemical reactions, and their contributions to the near-Sun environment. Comet-solar wind interactions are discussed, including the use of comets as probes of solar wind and coronal conditions in their vicinities. We address the relevance of work on comets near the Sun to similar objects orbiting other stars, and conclude with a discussion of future directions for the field and the planned ground- and space-based facilities that will allow us to address those science topics

Analysis of white light interferograms using wavelet methods

Several methods for the analysis of white light interferograms are presented and their performance is compared to a new method employing the wavelet transform in connection with sub-Nyquist sampling. As the result of computer simulations and experiments the wavelet method proves to be best suited to the problem

View planning for 3D reconstruction using time-of-flight camera data as a-priori information

Solving the next best view (NBV) problem is an important task for automated 3D reconstruction. An NBV algorithm provides sensor positions, from which maximal information gain about the measurement object during the next scan can be expected. With no or limited information available during the first views, automatic data driven view planning performs suboptimal. In order to overcome these inefficiencies during startup phase, we examined the use of time-of-flight (TOF) camera data to improve view planning. The additional low resolution 3D information, gathered during sensor movement, allows to plan even the first scans customized to previously unknown objects. Measurement examples using a robot mounted fringe projection stereo 3D scanner with a TOF camera are presented