Development of a device to simulate tooth mobility

Objectives: The testing of new materials under simulation of oral conditions is essential in medicine. For simulation of fracture strength different simulation devices are used for test set-up. The results of these in vitro tests differ because there is no standardization of tooth mobility in simulation devices. The aim of this study is to develop a simulation device that depicts the tooth mobility curve as accurately as possible and creates reproducible and scalable mobility curves. Materials and methods: With the aid of published literature and with the help of dentists, average forms of tooth classes were generated. Based on these tooth data, different abutment tooth shapes and different simulation devices were designed with a CAD system and were generated with a Rapid Prototyping system. Then, for all simulation devices the displacement curves were created with a universal testing machine and compared with the tooth mobility curve. With this new information, an improved adapted simulation device was constructed. Results: A simulations device that is able to simulate the mobility curve of natural teeth with high accuracy and where mobility is reproducible and scalable was developed

Investigation of the Afterglow Mode with the Caprice ECRIS for the GSI Heavy-Ion-Synchrotron operation

The Caprice-type ECRIS of the High Charge State Injector (HLI) of GSI predominantly has been operated in DC mode so far to deliver high duty cycle beams for the experimental area of the LINAC (UNILAC). The increasing demand of the Heavy Ion Synchrotron (SIS) for high intensities of heavy ion beams at very low duty cycle favours the application of the afterglow mode by pulsed operation of the ECRIS in these cases. Experiments with O, Ar, Xe and mainly with Pb were performed at the new ECR injector setup (EIS) which is a copy of the HLI injection beam line. Different RF pulse lengths and repetition rates were compared to optimise the respective afterglow intensities. For Pb two different types of ovens were investigated and modifications of the extraction system were applied. Thus peak intensities in the afterglow for 208Pb27+ of up to 200 emA could be obtained. Stable operation for time periods of several days could be achieved at reduced intensity level. Operational experiences are reported under the aspect of adaptation to SIS injection

3D modeling of the mechanical behavior of ceramics with pores of different size

Movable cellular automaton method was used for simulating uniaxial compression of 3D porous ceramic samples. Pores were considered explicitly by removing randomly selected automata from the original FCC packing. Distribution of pores in space, their size and the total fraction were varied. It is shown that the relation between mechanical properties of the material and its porosity significantly depends on the pore size. Thus, value of the elastic modulus of the samples with large pores is greater than that of the samples with small pores by average value of 3%-16%. Strength value of the samples with large pores is less than that of the samples with small pores by average value of 12% up to the porosity of 0.55, and then becomes to be greater. When the samples contain small and large pores there is a maximum of mechanical properties at ratio of volumes of large and small pores of about 0.75

Somatic neurofibromatosis type 1 (NF1) inactivation events in cutaneous neurofibromas of a single NF1 patient

Neurofibromatosis type 1 (NF1) (MIM#162200) is a relatively frequent genetic condition that predisposes to tumor formation. The main types of tumors occurring in NF1 patients are cutaneous and subcutaneous neurofibromas, plexiform neurofibromas, optic pathway gliomas, and malignant peripheral nerve sheath tumors. To search for somatic mutations in cutaneous (dermal) neurofibromas, whole-exome sequencing (WES) was performed on seven spatially separated tumors and two reference tissues (blood and unaffected skin) from a single NF1 patient. Validation of WES findings was done using routine Sanger sequencing or Sequenom IPlex SNP genotyping. Exome sequencing confirmed the existence of a known familial splice-site mutation NM_000267.3:c.3113+1G>A in exon 23 of NF1 gene (HGMD ID CS951480) in blood, unaffected skin, and all tumor samples. In five out of seven analyzed tumors, we additionally detected second-hit mutations in the NF1 gene. Four of them were novel and one was previously observed. Each mutation was distinct, demonstrating the independent origin of each tumor. Only in two of seven tumors we detected an additional somatic mutation that was not associated with NF1. Our study demonstrated that somatic mutations of NF1 are likely the main drivers of cutaneous tumor formation. The study provides evidence for the rareness of single base pair level alterations in the exomes of benign NF1 cutaneous tumors.European Journal of Human Genetics advance online publication, 8 October 2014; doi:10.1038/ejhg.2014.210