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Trocar insertion is a critical first step of all minimally invasive surgery; however, it also carries a high risk for errors. Studies suggest that entry errors are the most common complication in laparoscopic surgery with 4% of errors leading to patient fatality. Surgeon error due to excessive force is often the cause for entry errors; however, adequate training has been shown to reduce the risk of these surgical errors. In practice, institutions lack widespread and relatively inexpensive means to train surgeons for trocar entry that does not involve patient risk. In our prior work, we presented a simple Stewart platform haptic device with a numerical model to simulate key force characteristics of trocar insertion. Evaluation in our first study was limited to device characterization. In this paper, we present a more robust haptic mechanism with higher fidelity linear actuators, an increased workspace, and tissue visualization to accompany haptic cues. We also present a novel upper module that allows for a sudden drop of the trocar after the final puncture event to create a more realistic simulation. We performed a user study with eight novices to investigate how well the device and visualization train users in the trocar insertion procedure. By the end of the experiment, subjects using the device had a normalized error reduction of roughly 85% on average, relative to themselves. This device shows potential for widespread training of trocar insertion, possibly leading to fewer complications and deaths following the procedure. Finally, our upper module also represents an innovative addition for traditional admittance-type haptic device designs, not typically capable of accurately representing motion in free space. 

A growing body of literature has highlighted the importance of phytoplankton-bacterial associations to marine and estuarine ecological and biogeochemical function, but their population linkages remain sparsely characterized within urban estuaries. Since many developed coastlines are heavily impacted by anthropogenic nutrient inputs, elucidating their phytoplankton-bacterial dynamics provides insight into nutrient cycling, productivity, and can help inform water quality management. This study compared surface (0.5 m depth) physical water quality, cell abundances of major phytoplankton taxa and bacteria, as well as concentrations of chlorophylla(chla) and dissolved organic matter (DOM) in the nitrogen (N)-enriched Western Long Island Sound (WLIS), USA, between mid-channel and shore sites (in 2020 and 2021). Shore bacterial and phytoplankton abundances as well as DOM concentrations (primarily dissolved organic N and carbon [DOC]), were significantly higher than mid-channel, especially during summer, indicative of terrestrial loading influencing microbial assemblages as well as N and C cycling. Abundances of key phytoplankton taxa were better indicators of bacterial abundances than chla, as bacterial abundances positively and significantly correlated with those of dinoflagellates, especially the most common generaProrocentrum(mid-channel, shore) andHeterocapsa(shore only), but not with diatoms. However, pennate diatom abundances negatively and significantly correlated with DOC concentrations in the mid-channel. Results highlight the impact of terrestrial inputs on WLIS microbial assemblage dynamics, presumably by favoring bacteria and dinoflagellate population coupling, as well as shed new ecological insight into how phytoplankton and bacterial communities respond to nutrient loadings in urban estuaries. 

September 2023 marks the 50th anniversary of the Electronic Visualization Laboratory (EVL) at University of Illinois Chicago (UIC). EVL's introduction of the CAVE Automatic Virtual Environment in 1992, the first widely replicated, projection-based, walk-in, virtual-reality (VR) system in the world, put EVL at the forefront of collaborative, immersive data exploration and analytics. However, the journey did not begin then. Since its founding in 1973, EVL has been developing tools and techniques for real-time, interactive visualizations—pillars of VR. But EVL's culture is also relevant to its successes, as it has always been an interdisciplinary lab that fosters teamwork, where each person's expertise contributes to the development of the necessary tools, hardware, system software, applications, and human interface models to solve problems. Over the years, as multidisciplinary collaborations evolved and advanced scientific instruments and data resources were distributed globally, the need to access and share data and visualizations while working with colleagues, local and remote, synchronous and asynchronous, also became important fields of study. This paper is a retrospective of EVL's past 50 years that surveys the many networked, immersive, collaborative visualization and VR systems and applications it developed and deployed, as well as lessons learned and future plans.