DNA-dependent DNA-polymerases from Neurospora crassa

DNA-dependent DNA-polymerase

Organic Materials and Organic/Inorganic Heterostructures in Atom Probe Tomography

Nano-scale organic/inorganic interfaces are key to a wide range of materials. In many biominerals, for instance bone or teeth, outstanding fracture toughness and wear resistance can be attributed to buried organic/inorganic interfaces. Organic/inorganic interfaces at very small length scales are becoming increasingly important also in nano and electronic materials. For example, functionalized inorganic nanomaterials have great potential in biomedicine or sensing applications. Thin organic films are used to increase the conductivity of LiFePO4 electrodes in lithium ion batteries, and solid electrode interphases (SEI) form by uncontrolled electrolyte decomposition. Organics play a key role in dye-sensitized solar cells, organic photovoltaics, and nano-dielectrics for organic field-effect transistors. The interface between oxide semiconductors and polymer substrates is critical in emergent applications, for example, flexible displays

Iron phosphate mediated magnetite synthesis:a bioinspired approach

The biomineralization of intracellular magnetite in magnetotactic bacteria (MTB) is an area of active investigation. Previous work has provided evidence that magnetite biomineralization begins with the formation of an amorphous phosphate-rich ferric hydroxide precursor phase followed by the eventual formation of magnetite within specialized vesicles (magnetosomes) through redox chemical reactions. Although important progress has been made in elucidating the different steps and possible precursor phases involved in the biomineralization process, many questions still remain. Here, we present a novelin vitromethod to form magnetite directly from a mixed valence iron phosphate precursor, without the involvement of other known iron hydroxide precursors such as ferrihydrite. Our results corroborate the idea that phosphate containing phases likely play an iron storage role during magnetite biomineralization. Further, our results help elucidate the influence of phosphate ions on iron chemistry in groundwater and wastewater treatment.</p

UV-VIS spectra as potential process analytical technology (PAT) for measuring the density of compressed materials: Evaluation of the cielab color space

In this study, a novel approach was developed for determining the density of compacts using ultraviolet–visible spectrophotometry. The assumption within this context was that a change in density affects the corresponding color information of the compact. From the obtained spectra of the visible range, the color information of the compact was calculated which turned out to be directly proportional to the density of the compact. In comparison, the obtained spectra were analyzed using partial least square regression. The results of this study showed that both methods could be used predicting the density of a compact from the corresponding visible spectrum at identical accuracy. In contrast to the partial least square regression, the correlation of the color information as a direct output parameter of the spectrophotometer with the density required no excessive data pre-processing. Subsequently, the easier and faster data processing of the color information over the partial least square regression, conceives using this novel approach as potential process analytical technology tool for implementation into a compression process e.g., tableting or roller compaction

Meeting report: a hard look at the state of enamel research.

The Encouraging Novel Amelogenesis Models and Ex vivo cell Lines (ENAMEL) Development workshop was held on 23 June 2017 at the Bethesda headquarters of the National Institute of Dental and Craniofacial Research (NIDCR). Discussion topics included model organisms, stem cells/cell lines, and tissues/3D cell culture/organoids. Scientists from a number of disciplines, representing institutions from across the United States, gathered to discuss advances in our understanding of enamel, as well as future directions for the field

Time-resolved in situ studies on the formation mechanism of iron oxide nanoparticles using combined fast-XANES and SAXS

The reaction of iron chlorides with an alkaline reagent is one of the most prominent methods for the synthesis of iron oxide nanoparticles. We studied the particle formation mechanism using triethanolamine as reactant and stabilizing agent. In situ fast-X-ray absorption near edge spectroscopy and small-angle X-ray scattering provide information on the oxidation state and the structural information at the same time. In situ data were complemented by ex situ transmission electron microscopy, wide-angle X-ray scattering and Raman analysis of the formed nanoparticles. The formation of maghemite nanoparticles (gamma-Fe2O3) from ferric and ferrous chloride was investigated. Prior to the formation of these nanoparticles, the formation and conversion of intermediate phases (akaganeite, iron(II, III) hydroxides) was observed which undergoes a morphological and structural collapse. The thus formed small magnetite nanoparticles (Fe3O4) grow further and convert to maghemite with increasing reaction time

HPM-Detektionssystem mit Frequenzbestimmung

In allen Bereichen unserer Gesellschaft hält moderne und komplexe Elektronik Einzug. Mit zunehmender Komplexität und Vernetzung wächst auch das Potential für Bedrohung solcher kritischer Infrastruktur durch Hochleistungsmikrowellen (HPM), die solche Systeme zeitweise stören oder permanent außer Kraft setzen können. In der Vergangenheit wurde am Fraunhofer INT ein HPM-Detektionssystem entwickelt, dass über die Fähigkeiten einfacher Warnempfänger zur einfachen Anzeige von gefährlichen HPM-Ereignissen hinausgeht. In einem nächsten Schritt wurde mit einem vierkanaligen System die Detektion der Richtung eines HPM-Angriffs realisiert. Der Beitrag gliedert sich wie folgt: Vorüberlegungen für die HPM-Detektion (die zu einer analogen Ausführung des Detektors führen); Konzept zur HPM-Amplitudenmessung: Der Frequenzbereich erstreckt sich von 500 MHz bis etwa 4 GHz, die Messdynamik umfasst 60 dB, beginnend bei etwa 10 V/m. Die Schirmung des Demonstrators wurde erfolgreich bis 1 kV/m ausgemessen. Gepulste Signale konnten bis zu einer Kürze von 10 ns gemessen werden; Konzept zur HPM-Frequenzmessung (Prinzipschaltbild des HPM-Frequenzdiskriminators); Realisierung eines HPM-Detektionssystems mit Frequenzbestimmung (hierzu 5 Abb.: Kennlinie des Frequenzdiskriminators; Ausgangsimpuls des Frequenzdiskriminators, HF-Pulslänge = 100 ns; Blockschaltbild des HF-Teils des HPM-Detektors mit Frequenzmessung; Demonstrator des Konzeptes der Frequenzerkennung und einkanaliger Amplitudenmessung; Blockschaltbild des gesamten HPM-Detektors mit Frequenzmessung) sowie Softwarekonzept (Benutzeroberfläche). Das Konzept eines kompakten Gesamtsystems mit integrierter Spannungsversorgung und Signalübertragung per Lichtwellenleiter wurde im Labor, wie auch bei Freifeldmessungen, erfolgreich bestätigt