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Surface nuclear magnetic resonance (NMR) provides information not only on the lithology and water transport characteristics of aquifer systems but also on the state of iron mineralization within the pore space. This feature makes surface NMR a potential tool for the observation of changing redox conditions in the aquifer, which control the type and oxidation state of iron minerals and, relatedly, the buffering or release of pollutants that may pose a threat to drinking water resources. Our study aims on testing this potential and focuses on pyrite contained in the matrix of a sandy aquifer that serves as a natural denitrification buffer in a drinking water catchment area with intensive agricultural use. We observe a significant change in the surface-NMR relaxation times related to the pyrite content in the subsurface, which is most obvious at the transition from the pyrite-free oxic zone and the pyrite-bearing reducing zone. Complementary laboratory experiments using core material from the study site, including laboratory NMR and geochemical analyses, verify that the influence of pyrite content predominates the NMR relaxation behavior rather than pore size, porosity, or carbon content. The mean relaxation times measured in the sediment without pyrite exceed those with pyrite by approximately 20%–100%. We conclude that surface NMR can serve as a capable tool to locate and monitor the pyrite-based denitrification buffer. However, for general applicability within the given framework, more research is needed to address the natural ambiguity among iron content, its redox state and speciation, and pore size.

In this study, we report for the first time the use of the American oil palm (Elaeis oleifera) as roost by the Neotropical Pacific tent-making bat (Uroderma convexum). Palms with tent roosts consisting of modified leaves were found within the semi-deciduous lowland rainforest in Panama. We present detailed information on a new style of leaf modifications and compare these to tent architectures in other palm species used by U. convexum.

Lung cancer still has one of the highest morbidity and mortality rates among all types of cancer. Its incidence continues to increase, especially in developing countries. Although the medical field has witnessed the development of targeted therapies, new treatment options need to be developed urgently. For the discovery of new drugs, human cancer models are required to study drug efficiency in a relevant setting. Here, we report the generation of a non-small cell lung cancer model with a perfusion system. The bioprinted model was produced by digital light processing (DLP). This technique has the advantage of including simulated human blood vessels, and its simple assembly and maintenance allow for easy testing of drug candidates. In a proof-of-concept study, we applied gemcitabine and determined the IC50 values in the 3D models and 2D monolayer cultures and compared the response of the model under static and dynamic cultivation by perfusion. As the drug must penetrate the hydrogel to reach the cells, the IC50 value was three orders of magnitude higher for bioprinted constructs than for 2D cell cultures. Compared to static cultivation, the viability of cells in the bioprinted 3D model was significantly increased by approximately 60% in the perfusion system. Dynamic cultivation also enhanced the cytotoxicity of the tested drug, and the drug-mediated apoptosis was increased with a fourfold higher fraction of cells with a signal for the apoptosis marker caspase-3 and a sixfold higher fraction of cells positive for PARP-1. Altogether, this easily reproducible cancer model can be used for initial testing of the cytotoxicity of new anticancer substances. For subsequent in-depth characterization of candidate drugs, further improvements will be necessary, such as the generation of a multi-cell type lung cancer model and the lining of vascular structures with endothelial cells.

Because of its mobility and ability to investigate exposed surfaces, single-sided (SiS) nuclear magnetic resonance (NMR) technology enables new application fields in geosciences. To test and assess its corresponding potential, we compare longitudinal (T 1) and transverse (T 2) data measured by SiS NMR with those of conventional geoscientific laboratory NMR. We use reference sandstone samples covering a broad range of pore sizes. Our study demonstrates that the lower signal-to-noise ratio of SiS NMR data generally tends to slightly overestimated widths of relaxation time distributions and consequently pore size distributions. While SiS and conventional NMR produce very similar T 1 relaxation data, unbiased SiS NMR results for T 2 measurements can only be expected for fine material, i.e. clayey or silty sediments and soils with main relaxation times below 0.05 s . This limit is given by the diffusion relaxation rate due to the gradient in the primary magnetic field associated with the SiS NMR. Above that limit, i.e. for coarse material, the relaxation data is strongly attenuated. If considering the diffusion relaxation time of 0.2 s in the numerical data inversion process, the information content > 0.2 s is blurred over a range larger than that of conventional NMR. However, our results show that principle range and magnitudes of the relaxation time distributions are reconstructed to some extent. Regarding these findings, SiS NMR can be helpful to solve geoscientific issues, e.g. to assess the hydro-mechanical properties of the walls of underground facilities or to provide local soil moisture data sets for calibrating indirect remote techniques on the regional scale. The greatest opportunity provided by the SiS NMR technology is the acquisition of profile relaxation data for rocks with significant bedding structures at the μm scale. With this unique feature, SiS NMR can support the understanding and modeling of hydraulic and diffusional anisotropy behavior of sedimentary rocks.