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Summary:. The deep inferior epigastric perforator (DIEP) flap is the preferred method for autologous breast reconstruction after mastectomy, but risks the development of hernia, bulge, and decreased core strength. Robotic harvest of DIEP vessels may limit abdominal wall morbidity through smaller fascial incisions and preservation of motor nerves. This study shows the expected learning curve (LC) for robotic harvest and compares the LC between a general surgeon (GS) and a plastic surgeon (PS). A retrospective cohort study was performed for patients who underwent bilateral robotic DIEP flap harvest from October 2021 to September 2022. We evaluated robotic pedicle dissection time (DT) and compared the times between GS and PS. We calculated LC for each surgeon using the cumulative sum (CUSUM) method, CUSUM=∑i=1n(xi−μ−). The LC was identified as the peak of the CUSUM graph. Forty-four flap dissections were recorded during the collection period: 27 by the PS and 17 by the GS. There was no significant difference in DT between the GS and the PS (P = 0.366), and both surgeons saw a decrease in DT over time. Using the CUSUM method, we see the peak of the plot at patient 9 for the PS and the peak of the plot at patient 5 for the GS, after which cumulative DT decreased. As robotic harvest of DIEP flaps becomes accepted, plastic surgeons who wish to incorporate it into their practice may achieve proficiency in their DT within 10 flap harvests and a similar DT compared with robotic-trained GSs.

In the Nice model of Solar System formation, Uranus and Neptune undergo an orbital upheaval, sweeping through a planetesimal disk. The region of the disk from which material is accreted by the ice giants during this phase of their evolution has not previously been identified. We perform direct N -body orbital simulations of the four giant planets to determine the amount and origin of solid accretion during this orbital upheaval. We find that the ice giants undergo an extreme bombardment event, with collision rates as high as ∼3 per hour assuming km-sized planetesimals, increasing the total planet mass by up to ∼0.35%. In all cases, the initially outermost ice giant experiences the largest total enhancement. We determine that, for some plausible planetesimal properties, the resulting atmospheric enrichment could potentially produce sufficient latent heat to alter the planetary cooling timescale according to existing models. Our findings suggest that substantial accretion during this phase of planetary evolution may have been sufficient to impact the atmospheric composition and thermal evolution of the ice giants, motivating future work on the fate of deposited solid material.