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Solar-induced chlorophyll fluorescence (SIF) is used as a proxy of photosynthetic efficiency. However, interpreting top-of-canopy (TOC) SIF in relation to photosynthesis remains challenging due to the distortion introduced by the canopy's structural effects (i.e., fluorescence re-absorption, sunlit-shaded leaves, etc.) and sun-canopy-sensor geometry (i.e., direct radiation infilling). Therefore, ground-based, high-spatial-resolution data sets are needed to characterize the described effects and to be able to downscale TOC SIF to the leafs where the photosynthetic processes are taking place. We herein introduce HyScreen, a ground-based push-broom hyperspectral imaging system designed to measure red (F687) and far-red (F760) SIF and vegetation indices from TOC with single-leaf spatial resolution. This paper presents measurement protocols, the data processing chain and a case study of SIF retrieval. Raw data from two imaging sensors were processed to top-of-canopy radiance by dark-current correction, radiometric calibration, and empirical line correction. In the next step, the improved Fraunhofer line descrimination (iFLD) and spectral-fitting method (SFM) were used for SIF retrieval, and vegetation indices were calculated. With the developed protocol and data processing chain, we estimated a signal-to-noise ratio (SNR) between 50 and 200 from reference panels with reflectance from 5% to 95% and noise equivalent radiance (NER) of 0.04 (5%) to 0.18 (95%) mW m-2 sr-1 nm-1. The results from the case study showed that non-vegetation targets had SIF values close to 0 mW m-2 sr-1 nm-1, whereas vegetation targets had a mean F687 of 1.13 and F760 of 1.96 mW m-2 sr-1 nm-1 from the SFM method. HyScreen showed good performance for SIF retrievals at both F687 and F760; nevertheless, we recommend further adaptations to correct for the effects of noise, varying illumination and sensor optics. In conclusion, due to its high spatial resolution, Hyscreen is a promising tool for investigating the relationship between leafs and TOC SIF as well as their relationship with plants' photosynthetic capacity.

Short-wave infrared (SWIR) imaging systems with unmanned aerial vehicles (UAVs) are rarely used for remote sensing applications, like for vegetation monitoring. The reasons are that in the past, sensor systems covering the SWIR range were too expensive, too heavy, or not performing well enough, as, in contrast, it is the case in the visible and near-infrared range (VNIR). Therefore, our main objective is the development of a novel modular two-channel multispectral imaging system with a broad spectral sensitivity from the visible to the short-wave infrared spectrum (approx. 400 nm to 1700 nm) that is compact, lightweight and energy-efficient enough for UAV-based remote sensing applications. Various established vegetation indices (VIs) for mapping vegetation traits can then be set up by selecting any suitable filter combination. The study describes the selection of the individual components, starting with suitable camera modules, the optical as well as the control and storage parts. Special bandpass filters are used to select the desired wavelengths to be captured. A unique flange system has been developed, which also allows the filters to be interchanged quickly in order to adapt the system to a new application in a short time. The characterization of the system was performed in the laboratory with an integrating sphere and a climatic chamber. Finally, the integration of the novel modular VNIR/SWIR imaging system into a UAV and a subsequent first outdoor test flight, in which the functionality was tested, are described.

Purpose: We studied a group of patients with polymyalgia rheumatica (PMR) with or without biopsy-proven giant cell arteritis (GCA) in order to determine the prevalence of anticardiolipin antibodies (aCL) in these disorders and their association with vascular complications., Patients and Methods: The study consisted of 50 patients, 30 with PMR alone and 20 with associated GCA. Determinations of IgG and IgM aCL by enzyme-linked immunosorbent assay were done in the patients and in 50 age- and sex-matched healthy control subjects. We also measured von Willebrand factor (vWF) antigen, C-reactive protein, and erythrocyte sedimentation rate., Results: Twenty-four (48%) of the 50 patients had aCL. Eleven were positive for IgG and five for IgM, whereas eight were positive for both. In the group of patients with PMR alone, only eight (26.6%) had aCL, while 16 of 20 patients (80%) with GCA had these antibodies (p less than 0.01). In the control group, 10 of 50 patients (20%) had positive aCL, a finding that was statistically significantly different only when compared with the finding in patients with GCA (p less than 0.01). Both isotypes of aCL were seen mainly in patients with GCA, and five of these patients had severe vascular complications. Levels of vWF antigen were significantly higher in patients with GCA as compared with patients with PMR alone; however, the highest titers did not correlate with vascular complications. Erythrocyte sedimentation rate and C-reactive protein were increased but comparable in both groups., Conclusion: This study demonstrates that aCL are prevalent in patients with GCA. These antibodies might imply severe vascular damage and could play an important role in the pathogenesis of the vasculopathy observed in this disease.

Trivalent cations of the lanthanide series (La3+----Yb3+) stimulated uptake of proline or glucose in rabbit small intestinal brush-border membrane vesicles. The lanthanides stimulated uptake to an extent greater than Al3+, choline, and in many cases, Na+. A time-course of Er3+-stimulated glucose uptake gave initial rates and overshoots greater than Na+ stimulation. The best activators were Sm3+, Eu3+ and Tm3+, which stimulated proline initial uptakes by 400-600%, and stimulated glucose uptake by 120-150%, compared to Na+. The best lanthanide cotransport activators possessed high third ionization potentials.