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Ohne ZusammenfassungMitteilungaus dem Nahrungsmittel-Untersuchungsamtder Landwirtschaftskammer für die Provinz Brandenburg in BerlinUnter analytischer Mitwirkung von Frl. Dr. Blum und Dr. F. Amonn.  相似文献   
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European Food Research and Technology -  相似文献   
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A new concept for the enrichment of lithium minerals is offering higher purity and higher yield by applying new processing technologies addressing the specific properties of the pegmatitic host rock. Additional value is created from high quality by-products which will improve the sustainability of mining activity and the overall cost base. Within the new concept, flotation may even be avoided where wet separation techniques are not applicable.Two innovative processing technologies have been integrated in the new concept: electrodynamic fragmentation and optical sorting. Detailed results of lab-technical tests show that the new process design can achieve highly selective liberation and separation processes. Optical and mineralogical analyses of the test products indicate a high benefit for commercial applications.  相似文献   
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The corrosion processes are presumed to have negative consequences on biocompatibility, aesthetic appearance and the frictional behavior between the bracket and the guiding arch during orthodontic treatment. A group of new guiding arches are the coated orthodontic wires. The present in-vitro study investigated the corrosion behavior and permanent fracture resistance of eight coated wires of different dimensions. Five superelastic nickel titanium (NiTi) wires (Titanol® Low Force River Finish Gold and Gold 2: Forestadent Corp.; Titanol® Superelastic tooth colored: Forestadent Corp.; Bioforce Sentalloy longuard: GAC Corp.; NiTi Imagination: GAC Corp.), two -titanium-wires (TMA Low Friction longuard: Ormco Corp.; TMA Low Friction longuard Purple: Ormco Corp.) and one steel wire (Stainless Steel Imagination: GAC Corp.) were selected. For comparison reasons three uncoated arch wires (Rematitan® Lite Dimple: Dentaurum Corp.; Titanol® Low Force River Finish: Forestadent Corp.; Bioforce Sentalloy: GAC Corp.) were included in the investigation. Surface modifications were made of teflon, polyethylene and by ion implantation. The corrosion processes have been carried out by the use of a specialized electrochemical cell. In a second experimental series the wires were exposed to mechanical stresses. Finally, all wires were examined in a scanning electron microscope. The results indicated that teflon coating prevented the corrosion of the wires. As expected, the -titanium wires did not corrode either. The other wires showed rupture potentials between 187 mV and 602 mV (NHE). After mechanical stress testing the wires could be subdivided into three groups. In the first group no differences could be recognized, the second group showed changes in their crystallographic structure and in the last group the teflon coating was peeled off from the surface of the wires.  相似文献   
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To evaluate the relative ability of those striatal neuron types containing calbindin or parvalbumin to withstand a Ca(2+)-mediated excitotoxic insult, we injected the NMDA receptor-specific excitotoxin quinolinic acid (QA) into the striatum in mature adult rats and 2 months later examined the relative survival of striatal interneurons rich in parvalbumin and striatal projection neurons rich in calbindin. To provide standardization to the survival of striatal neuron types thought to be poor in Ca2+ buffering proteins, the survival was compared to that of somatostatin-neuropeptide Y (SS/NPY)-containing interneurons and enkephalinergic projection neurons, which are devoid of or relatively poorer in such proteins. The various neuron types were identified by immunohistochemical labeling for these type-specific markers and their relative survival was compared at each of a series of increasing distances from the injection center. In brief, we found that parvalbuminergic, calbindinergic, and enkephalinergic neurons all showed a generally comparable gradient of neuronal loss, except just outside the lesion center, where calbindin-rich neurons showed significantly enhanced survival. In contrast, striatal SS/NPY interneurons were more vulnerable to QA than any of these three other types. These observed patterns of survival following intrastriatal QA injection suggest that calbindin and parvalbumin content does not by itself determine the vulnerability of striatal neurons to QA-mediated excitotoxicity in mature adult rats. For example, parvalbuminergic striatal interneurons were not impervious to QA, while cholinergic striatal interneurons are highly resistant and SS/NPY+ striatal interneurons are highly vulnerable. Both cholinergic and SS/NPY+ interneurons are devoid of any known calcium buffering protein. Similarly, calbindin does not prevent striatal projection neuron vulnerability to QA excitotoxicity. Nonetheless, our data do suggest that calbindin may offer striatal neurons some protection against moderate excitotoxic insults, and this may explain the reportedly slightly greater vulnerability of striatal neurons that are poor in calbindin to ischemia and Huntington's disease.  相似文献   
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