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ABSTRACT Marine pest introductions continue to occur and increase at accelerated rates, threatening the marine environment and blue economy. Environmental DNA (eDNA) is a tool for determining the presence of both indigenous and nonindigenous species, via the detection of genetic material that is shed into the local environment. Although eDNA approaches have gained widespread adoption in the last decade, fundamental knowledge gaps remain around factors that can influence the probability of detection, and how to optimize eDNA sampling in aquatic environments. Here, we partition eDNA research into four major research themes: eDNA concentration (shedding and decay), transport (advection and mixing), sampling design strategies, and the modeling of these dynamics. We review current developments and challenges in each theme with a focus on field sampling strategies and the use of biophysical models for understanding the movement of modeling eDNA in complex aquatic environments. We then introduce three modeling case studies from a large embayment where we (1) quantify the spatial and temporal variability of eDNA dispersion, (2) use biophysical models to inform a field sampling strategy, and (3) demonstrate a backtracking modeling technique to identify upstream DNA sources to an existing sample (monitoring) site. We conclude by identifying specific recommendations to help improve future eDNA studies. This work highlights how biophysical models can be applied to improve early detection and informing response and management decisions.

Abstract Here, an in vitro characterization of a family of prazole derivatives that covalently bind to the C73 site on Tsg101 and assay their ability to inhibit viral particle production is presented. Structurally, increased steric bulk on the 4‐pyridyl of the prazole expands the prazole site on the UEV domain toward the β‐hairpin in the Ub‐binding site and is coupled to increased inhibition of virus‐like particle production in HIV‐1. Increased bulk also increased toxicity, which is alleviated by increasing flexibility. Further, the formation of a novel secondary Tsg101 adduct for several of the tested compounds and the commercial drug lansoprazole. The secondary adduct involved the loss of the 4‐pyridyl substituent to form an irreversible species, with implications for increasing the half‐life of the active species or its specificity toward Tsg101 UEV. It is also determined that sulfide derivatives display effective viral inhibition, presumably through cellular sulfoxidation, allowing for delayed conversion within the cellular environment, and identify SARS‐COV‐2 as a target of prazole inhibition. These results open multiple avenues for the design of prazole derivatives for antiviral applications.

Abstract High‐resolution spatio‐temporal monitoring of the cell membrane lipid order provides visual insights into the complex and sophisticated systems that control cellular physiological functions. Solvatochromic fluorescent probes are highly promising noninvasive visualization tools for identifying the ordering of the microenvironment of plasma membrane microdomains. However, conventional probes, although capable of structural analysis, lack the necessary long‐term photostability required for live imaging at the cellular level. Here, an ultra‐high‐light‐resistant solvatochromic fluorescence probe, 2‐N,N‐diethylamino‐7‐(4‐methoxycarbonylphenyl)‐9,9‐dimethylfluorene (FπCM) is reported, which enables live lipid order imaging of cell division. This probe and its derivatives exhibit sufficient fluorescence wavelengths, brightness, polarity responsiveness, low phototoxicity, and remarkable photostability under physiological conditions compared to conventional solvatochromic probes. Therefore, these probes have the potential to overcome the limitations of fluorescence microscopy, particularly those associated with photobleaching. FπCM probes can serve as valuable tools for elucidating mechanisms of cellular processes at the bio‐membrane level.

Abstract In this study, a novel, high content technique using a cylindrical acoustic transducer, stroboscopic fast imaging, and homodyne detection to recover the mechanical properties (dynamic shear modulus) of living adherent cells at low ultrasonic frequencies is presented. By analyzing the micro‐oscillations of cells, whole populations are simultaneously mechanotyped with sub‐cellular resolution. The technique can be combined with standard fluorescence imaging allowing to further cross‐correlate biological and mechanical information. The potential of the technique is demonstrated by mechanotyping co‐cultures of different cell types with significantly different mechanical properties.