DigitalMaschinenbau und Mechatronik
M. Schmid, S. Zabler, E. Hofmann, M. Hofmeister, Jochen Hiller, A. Hölzing, J. Engel, K.-H. Hiller, P. Jakob, U. Hirschenfelder, A. Detterbeck, D. Haddad, D. Weber
Determination of the mesio-distal tooth width via 3D imaging techniques with and without ionizing radiation: CBCT, MSCT, and μCT versus MRI
European Journal of Orthodontics, vol. 39, no. 3, pp. 310-319
The purpose of this study was to estimate the feasibility and accuracy of mesio-distal width measurements with magnetic resonance imaging (MRI) in comparison to conventional 3D imaging techniques [multi-slice CT (MSCT), cone-beam CT (CBCT), and µCT]. The measured values of the tooth widths were compared to each other to estimate the amount of radiation necessary to enable orthodontic diagnostics.
Material and Methods:
Two pig skulls were measured with MSCT, CBCT, µCT, and MRI. Three different judges were asked to determine the mesio-distal tooth width of 14 teeth in 2D tomographic images and in 3D segmented images via a virtual ruler in every imaging dataset.
Approximately 19% (27/140) of all test points in 2D tomographic slice images and 12% (17/140) of the test points in 3D segmented images showed a significant difference (P ≤ 0.05). The largest significant difference was 1.6mm (P < 0.001). There were fewer significant differences in the measurement of the tooth germs than in erupted teeth.
Measurement of tooth width by MRI seems to be clinically equivalent to the conventional techniques (CBCT and MSCT). Tooth germs are better illustrated than erupted teeth on MRI. Three-dimensional segmented images offer only a slight advantage over 2D tomographic slice images. MRI, which avoids radiation, is particularly appealing in adolescents if these data can be corroborated in further studies.
S. Kuphal, P. Schummer, L. Vardimon, Melanie Kappelmann-Fenzl, A. Bosserhoff
Specific c-Jun target genes in malignant melanoma
Cancer Biology & Therapy, vol. 17, no. 5, pp. 486-497
A fundamental event in the development and progression of malignant melanoma is the de-regulation of cancer-relevant transcription factors. We recently showed that c-Jun is a main regulator of melanoma progression and, thus, is the most important member of the AP-1 transcription factor family in this disease. Surprisingly, no cancer-related specific c-Jun target genes in melanoma were described in the literature, so far. Therefore, we focused on pre-existing ChIP-Seq data (Encyclopedia of DNA Elements) of 3 different non-melanoma cell lines to screen direct c-Jun target genes. Here, a specific c-Jun antibody to immunoprecipitate the associated promoter DNA was used. Consequently, we identified 44 direct c-Jun targets and a detailed analysis of 6 selected genes confirmed their deregulation in malignant melanoma. The identified genes were differentially regulated comparing 4 melanoma cell lines and normal human melanocytes and we confirmed their c-Jun dependency. Direct interaction between c-Jun and the promoter/enhancer regions of the identified genes was confirmed by us via ChIP experiments. Interestingly, we revealed that the direct regulation of target gene expression via c-Jun can be independent of the existence of the classical AP-1 (5´-TGA(C/G)TCA-3´) consensus sequence allowing for the subsequent down- or up-regulation of the expression of these cancer-relevant genes. In summary, the results of this study indicate that c-Jun plays a crucial role in the development and progression of malignant melanoma via direct regulation of cancer-relevant target genes and that inhibition of direct c-Jun targets through inhibition of c-Jun is a potential novel therapeutic option for treatment of malignant melanoma.
Europan Campus Rottal-Inn
M. Seebauer, V. Grimm, Robert Feicht
An experimental study of corporate social responsibility through charitable giving in Bertrand markets
Journal of Economic Behavior & Organization, vol. 124, no. April, pp. 88-101
We experimentally investigate a Bertrand market with homogenous goods in which sellers can announce the donation of a share of their profits to an existing non-profit organization. In a 2 × 2 design, we vary the credibility of announcements and the efficiency of the contributions to the public fund. We find that sellers’ donations are strictly positive independently of the credibility of the announcements, and their donations are higher if announcements are credible and efficiency is high. However, market outcomes in terms of prices and profits do not differ significantly in any treatment that allows for contributions to a public fund. Analysis of buyer decisions reveals that prices are the main driver of purchase decisions while higher donations only affect purchase decisions when they are credible and price differences are negligible. Our results indicate that under intense competition the possibility of attracting customers through corporate social responsibility activities is limited, although the constant positive level of contributions suggests that norms lead to a certain minimum level of corporate social responsibility.
NachhaltigEuropan Campus Rottal-Inn
G. Denuault, M. Mátéfi-Tempfli, H. Bülter, C. Dosche, Stefan Mátéfi-Tempfli, G. Wittstock
Electrochemical analysis of nanostructured iron oxides using cyclic voltammetry and scanning electrochemical microscopy
Electrochimica Acta, vol. 222, pp. 1326-1334
Iron oxides in general and especially hematite, α-Fe2O3, have become promising materials for the alkaline water electrolysis and photoelectrochemical water splitting, respectively. In the present study electrocatalytic electrodes with a thin film of α-Fe2O3 and with vertically aligned α-Fe2O3 nanowires were prepared. Cyclic voltammograms of the α-Fe2O3 nanowires revealed differences including a series of three unreported cathodic signals when compared to previously published voltammograms for polycrystalline iron oxides. The generation-collection mode of scanning electrochemical microscopy (SECM) using nanostructured Pt microdisc probes was exploited to detect soluble reaction products formed at the voltammetric peaks of the α-Fe2O3 electrode. SECM tip-substrate voltammetry unexpectedly showed that the reduction of FeVI to FeIII on the cathodic sweep is accompanied by significant O2 evolution.