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Philipp Strobel

Publications and source records attributed to Philipp Strobel.

2 recordsLinked to original sources

A Multimodal Dataset for Survival Prediction in Resected Pancreatic Ductal Adenocarcinoma

Survival research in pancreatic ductal adenocarcinoma (PDAC) is limited by the scarcity of datasets linking whole-slide histology with clinical, molecular, and long-term outcome data. We present a retrospective single-centre cohort of 302 patients who underwent PDAC resection at University Medical Center Gottingen. The dataset comprises 446 H&E whole-slide images, clinicopathological variables, targeted sequencing data for 154 patients, and overall-survival outcomes. During follow-up, 253 patients died, and the median follow-up was 76 months. To establish initial reference values, we evaluated fourteen survival-prediction configurations using identical five-repetition Monte Carlo cross-validation partitions. Ridge Cox regression using numeric clinicopathological variables achieved a mean concordance of $0.649 \pm 0.042$ and $0.652 \pm 0.046$ after adding KRAS and TP53 mutation status. The image-only attention model achieved $0.603 \pm 0.030$, while multimodal fusion achieved $0.619 \pm 0.025$, the highest concordance among the neural models. These results establish promising initial benchmarks for future research using this pancreas-specific multimodal dataset, paving the way for external validation.

cs.CV↗

Emergence of photoswitchable states in a graphene-azobenzene-Au platform

The perfect transmission of charge carriers through potential barriers in graphene (Klein tunneling) is a direct consequence of the Dirac equation that governs the low-energy carrier dynamics. As a result, localized states do not exist in unpatterned graphene, but quasi-bound states \emph{can} occur for potentials with closed integrable dynamics. Here, we report the observation of resonance states in photo-switchable self-assembled molecular(SAM)-graphene hybrid. Conductive AFM measurements performed at room temperature reveal strong current resonances, the strength of which can be reversibly gated \textit{on-} and \textit{off-} by optically switching the molecular conformation of the mSAM. Comparisons of the voltage separation between current resonances ($\sim 70$--$120$ mV) with solutions of the Dirac equation indicate that the radius of the gating potential is $\sim 7 \pm 2$ nm with a strength $\geq 0.5$ eV. Our results and methods might provide a route toward \emph{optically programmable} carrier dynamics and transport in graphene nano-materials.

cond-mat.mtrl-sci↗