TY - GEN A1 - Strobel, Carsten A1 - Alvarado Chavarin, Carlos A1 - Völkel, Sandra A1 - Jahn, Andreas A1 - Hiess, Andre A1 - Knaut, Martin A1 - Albert, Matthias A1 - Wenger, Christian A1 - Steinke, Olaff A1 - Stephan, Ulf A1 - Röhlecke, Sören A1 - Mikolajick, Thomas T1 - Enhanced Electrical Properties of Optimized Vertical Graphene-Base Hot Electron Transistors T2 - ACS Applied Electronic Materials N2 - The arrival of high-mobility two-dimensional materials like graphene leads to the renaissance of former vertical semiconductor–metal–semiconductor (SMS) hot electron transistors. Because of the monolayer thickness of graphene, improved SMS transistors with a semimetallic graphene-base electrode are now feasible for high-frequency applications. In this study we report about a device that consists of amorphous silicon, graphene, and crystalline silicon. For the first time, this device is fabricated by a four-mask lithography process which leads to significant improvements in the device performance. A strongly increased common-emitter current gain of 2% could be achieved while the on–off ratio improved to 1.6 × 105, which is already higher than predicted theoretically. This could be mainly attributed to better interface characteristics and decreased lateral dimensions of the devices. A cutoff frequency of approximately 26 MHz could be forecasted based on the DC measurements of the device. KW - Graphene KW - Transistor Y1 - 2023 U6 - https://doi.org/10.1021/acsaelm.2c01725 SN - 2637-6113 VL - 5 IS - 3 SP - 1670 EP - 1675 ER - TY - GEN A1 - Aubele, Maria A1 - Grill, Eva A1 - Eggert, Thomas A1 - Schneider, Erich A1 - Strobl, Ralf A1 - Jahn, Klaus A1 - Müller, Martin A1 - Holle, Rolf A1 - Linkohr, Birgit A1 - Heier, Margit A1 - Ladwig, Karl-Heinz A1 - Lehnen, Nadine T1 - Symptoms in unilatral vestibular hypofunction are associated with number of catch-up saccades and retinal errors: results from the population-based KORA FF4study T2 - Frontiers in Neurology N2 - Objective: The presence and intensity of symptoms vary in patients with unilateral vestibular hypofunction. We aimed to determine which saccadic and vestibulo-ocular reflex parameters best predict the presence of symptoms in unilateral vestibular hypofunction in order to better understand vestibular compensation and its implications for rehabilitation therapy. Methods: Video head impulse test data were analyzed from a subpopulation of 23 symptomatic and 10 currently symptom-free participants with unilateral vestibular hypofunction, embedded in the KORA (Cooperative Health Research in the Region of Augsburg) FF4 study, the second follow-up of the KORA S4 population-based health survey (2,279 participants). Results: A higher number of catch-up saccades, a higher percentage of covert saccades, and a larger retinal error at 200 ms after the onset of the head impulse were associated with relevant symptoms in participants with unilateral vestibular hypofunction (p = 0.028, p = 0.046, and p = 0.038, respectively). After stepwise selection, the number of catch-up saccades and retinal error at 200 ms remained in the final logistic regression model, which was significantly better than a null model (p = 0.014). Age, gender, saccade amplitude, saccade latency, and VOR gain were not predictive of the presence of symptoms. Conclusion: The accuracy of saccadic compensation seems to be crucial for the presence of symptoms in unilateral vestibular hypofunction, highlighting the role of specific gaze stabilization exercises in rehabilitation. Early saccades, mainly triggered by the vestibular system, do not seem to compensate accurately enough, resulting in a relevant retinal error and the need for more as well as more accurate catch-up saccades, probably triggered by the visual system. KW - video head impulse test, vHIT, catch-up saccades, unilateral vestibular hypofunction, retinal error, vestibulo-ocular reflex, VOR, population-based survey Y1 - 2023 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10715252/ SN - 1664-2295 VL - 2023 IS - 14 ER - TY - GEN A1 - Herrmann, Ludger A1 - Jahn, Reinhold A1 - Maurer, Thomas T1 - Mineral dust around Sahara - from source to sink. A review with emphasis on contributions of the German soil science community in the last twenty years T2 - Journal of Plant Nutrition and Soil Science Y1 - 2010 SN - 1522-2624 VL - 173 IS - 6 SP - 811 EP - 821 ER -