@article{OpolkaMuellerFellaetal.2021, author = {Opolka, Alexander and M{\"u}ller, Dominik and Fella, Christian and Balles, Andreas and Mohr, J{\"u}rgen and Last, Arndt}, title = {Multi-lens array full-field X-ray microscopy}, series = {Applied Sciences}, volume = {11}, journal = {Applied Sciences}, number = {16}, issn = {2076-3417}, doi = {10.3390/app11167234}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-244974}, year = {2021}, abstract = {X-ray full-field microscopy at laboratory sources for photon energies above 10 keV suffers from either long exposure times or low resolution. The photon flux is mainly limited by the objectives used, having a limited numerical aperture NA. We show that this can be overcome by making use of the cone-beam illumination of laboratory sources by imaging the same field of view (FoV) several times under slightly different angles using an array of X-ray lenses. Using this technique, the exposure time can be reduced drastically without any loss in terms of resolution. A proof-of-principle is given using an existing laboratory metal-jet source at the 9.25 keV Ga K\(_α\)-line and compared to a ray-tracing simulation of the setup.}, language = {en} } @article{MuellerGraetzBallesetal.2021, author = {M{\"u}ller, Dominik and Graetz, Jonas and Balles, Andreas and Stier, Simon and Hanke, Randolf and Fella, Christian}, title = {Laboratory-Based Nano-Computed Tomography and Examples of Its Application in the Field of Materials Research}, series = {Crystals}, volume = {11}, journal = {Crystals}, number = {6}, issn = {2073-4352}, doi = {10.3390/cryst11060677}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241048}, year = {2021}, abstract = {In a comprehensive study, we demonstrate the performance and typical application scenarios for laboratory-based nano-computed tomography in materials research on various samples. Specifically, we focus on a projection magnification system with a nano focus source. The imaging resolution is quantified with common 2D test structures and validated in 3D applications by means of the Fourier Shell Correlation. As representative application examples from nowadays material research, we show metallization processes in multilayer integrated circuits, aging in lithium battery electrodes, and volumetric of metallic sub-micrometer fillers of composites. Thus, the laboratory system provides the unique possibility to image non-destructively structures in the range of 170-190 nanometers, even for high-density materials.}, language = {en} } @article{BazihizinaBoehmMessereretal.2022, author = {Bazihizina, Nadia and B{\"o}hm, Jennifer and Messerer, Maxim and Stigloher, Christian and M{\"u}ller, Heike M. and Cuin, Tracey Ann and Maierhofer, Tobias and Cabot, Joan and Mayer, Klaus F. X. and Fella, Christian and Huang, Shouguang and Al-Rasheid, Khaled A. S. and Alquraishi, Saleh and Breadmore, Michael and Mancuso, Stefano and Shabala, Sergey and Ache, Peter and Zhang, Heng and Zhu, Jian-Kang and Hedrich, Rainer and Scherzer, S{\"o}nke}, title = {Stalk cell polar ion transport provide for bladder-based salinity tolerance in Chenopodium quinoa}, series = {New Phytologist}, volume = {235}, journal = {New Phytologist}, number = {5}, doi = {10.1111/nph.18205}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-287222}, pages = {1822 -- 1835}, year = {2022}, abstract = {Chenopodium quinoa uses epidermal bladder cells (EBCs) to sequester excess salt. Each EBC complex consists of a leaf epidermal cell, a stalk cell, and the bladder. Under salt stress, sodium (Na\(^{+}\)), chloride (Cl\(^{-}\)), potassium (K\(^{+}\)) and various metabolites are shuttled from the leaf lamina to the bladders. Stalk cells operate as both a selectivity filter and a flux controller. In line with the nature of a transfer cell, advanced transmission electron tomography, electrophysiology, and fluorescent tracer flux studies revealed the stalk cell's polar organization and bladder-directed solute flow. RNA sequencing and cluster analysis revealed the gene expression profiles of the stalk cells. Among the stalk cell enriched genes, ion channels and carriers as well as sugar transporters were most pronounced. Based on their electrophysiological fingerprint and thermodynamic considerations, a model for stalk cell transcellular transport was derived.}, language = {en} }