Search for: All records

Minimally Invasive Surgery lacks tactile feedback that surgeons find useful for finding and diagnosing tissue abnormalities. The goal of this paper is to calibrate sensors of a motorized Smart Grasper surgical instrument to provide accurate force and position measurements. These values serve two functions with the novel calibration hardware. The first is to control the motor of the Grasper to prevent tissue damage. The second is to act as the base upon which future work in multi-modal sensor fusion tissue characterization can be built. Our results show that the Grasper jaw distance is a function of both applied force and motor angle while the force the jaws apply to the tissue can be measured using the internal load cell. All code and data sets used to generate this paper can be found on GitHub at https://github.com/Yana-Sosnovskaya/ Smart Grasper public 

Abstract Biological invasions are usually examined in the context of their impacts on native species. However, few studies have examined the dynamics between invaders when multiple exotic species successfully coexist in a novel environment. Yet, long‐term coexistence of now established exotic species has been observed in North American lady beetle communities. Exotic lady beetlesHarmonia axyridisandCoccinella septempunctatawere introduced for biological control in agricultural systems and have since become dominant species within these communities. In this study, we investigated coexistence via spatial and temporal niche partitioning amongH. axyridisandC. septempunctatausing a 31‐year data set from southwestern Michigan, USA. We found evidence of long‐term coexistence through a combination of small‐scale environmental, habitat, and seasonal mechanisms. Across years,H. axyridisandC. septempunctataexperienced patterns of cyclical dominance likely related to yearly variation in temperature and precipitation. Within years, populations ofC. septempunctatapeaked early in the growing season at 550 degree days, whileH. axyridispopulations grew in the season until 1250 degree days and continued to have high activity after this point.C. septempunctatawas generally most abundant in herbaceous crops, whereasH. axyridisdid not display strong habitat preferences. These findings suggest that within this regionH. axyridishas broader habitat and abiotic environmental preferences, whereasC. septempunctatathrives under more specific ecological conditions. These ecological differences have contributed to the continued coexistence of these two invaders. Understanding the mechanisms that allow for the coexistence of dominant exotic species contributes to native biodiversity conservation management of invaded ecosystems.