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Historic gardens are green spaces characterised by tree stands with several veteran specimens of high artistic and cultural value. Such valuable plant components have to cope with biotic and abiotic stress factors as well as ongoing senescence processes. Maintaining tree health is therefore crucial to preserve their ecosystem services, but also to protect the monument and visitor health. In this context, finding smart, fast and cost-effective management solutions to monitor health and detect critical conditions for both stands and individual veteran trees can promote garden conservation. For this reason, we developed a novel framework based on Sentinel2 imagery, LiDAR sources and automatic cameras to identify risk spots regarding trees in historic gardens. The pilot study area consists of two closed Italian gardens from the 16th century, which were analysed as a unique Historic Garden System (HGS). The tree health status at stand level was assessed using a criterion based on the Normalized Difference Vegetation Index weighed on tree volume (NDVI t ) and validated by a visual crown defoliation assessment. At the tree level, the health status of four veteran trees defined by the NDVI t was also evaluated using green chromatic coordinates (GCC) obtained from digital images acquired by cameras at daily intervals during one growing season. The 33% of the tree population was classified as being in poor health, i.e. "at risk". Veteran trees classified as "at risk" showed an anticipation of phenological phases and a lower GCC compared to reference trees. Despite variability determined by Sentinel medium resolution, the proposed framework showed good accuracy (0.74) for monitoring historical gardens. The semi-automatic risk point mapping system tested here proved to be effective in facilitating the management of historic gardens, which in turn could be applied in the wider context of urban greening., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Light scattering was recently demonstrated to serve as an intrinsic indicator for pancreatic islet cell mass and secretion. The insulin secretory granule (ISG), in particular, was proposed to be a reasonable candidate as the main intracellular source of scattered light due to the densely-packed insulin semi-crystal in the granule lumen. This scenario, if confirmed, would in principle open new perspectives for label-free single-granule imaging, tracking, and analysis. Contrary to such expectations, here we demonstrate that ISGs are not a primary source of scattering in primary human β-cells, as well as in immortalized β-like cells, quantitatively not superior to other intracellular organelles/structures, such as lysosomes and internal membranes. This result is achieved through multi-channel imaging of scattered light along with fluorescence arising from selectively-labelled ISGs. Co-localization and spatiotemporal cross-correlation analysis is performed on these signals, and compared among different cell lines. Obtained results suggest a careful re-thinking of the possibility to exploit intrinsic optical properties originating from ISGs for single-granule imaging purposes., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Lysosomes are not merely degradative organelles but play a central role in nutrient sensing, metabolism and cell-growth regulation. Our ability to study their function in living cells strictly relies on the use of lysosome-specific fluorescent probes tailored to optical microscopy applications. Still, no report thus far quantitatively analyzed the effect of labeling strategies/procedures on lysosome properties in live cells. We tackle this issue by a recently developed spatiotemporal fluctuation spectroscopy strategy that extracts structural (size) and dynamic (diffusion) properties directly from imaging, with no a-priori knowledge of the system. We highlight hitherto neglected alterations of lysosome properties upon labeling. In particular, we demonstrate that Lipofectamine reagents, used to transiently express lysosome markers fused to fluorescent proteins (FPs) (e.g. LAMP1-FP or CD63-FP), irreversibly alter the organelle structural identity, inducing a ∼2-fold increase of lysosome average size. The organelle structural identity is preserved, instead, if electroporation or Effectene are used as transfection strategies, provided that the expression levels of the recombinant protein marker are kept low. This latter condition can be achieved also by generating cell lines stably expressing the desired FP-tagged marker. Reported results call into question the interpretation of a massive amount of data collected so far using fluorescent protein markers and suggest useful guidelines for future studies., (Copyright © 2018 Elsevier Inc. All rights reserved.)