The current clinical gold standards for tissue sealing include sutures, staples, and glues, however several adverse effects limit their use. Sutures and staples inherently cause additional trauma to tissue surrounding the wound, and glues can be lacking in adhesion and are potentially inflammatory. All three also introduce risk of infection. Light-activated tissue sealing, particularly the use of near-infrared light, is an attractive alternative, as it localizes heat, thereby preventing thermal damage to the surrounding healthy tissue. Previous work identified a glutaraldehyde-crosslinked chitosan film as a lead sealant for gastrointestinal incision sealing, but in vivo testing resulted in tissue degradation in and around the wound. The suggested causes for this degradation were excess acetic acid, endotoxins in the chitosan, and thermal damage. A basic buffer wash protocol was developed to remove excess acid from the films following fabrication. UV-Vis spectroscopy demonstrated that following the wash, films had the same concentration of Indocyanine green as unwashed films, allowing them to absorb light at the same wavelength, therefore showing the wash did not affect the film’s function. However subsequent washes led to degradation of film mass of nearly 20%. Standard chitosan films had significantly greater mass gain (p = 0.028) and significantly less subsequent loss (p= 0.012) than endotoxin free chitosan-films after soaking in phosphate buffered saline for varying durations , while soaking duration had no effect (p = 0.332). Leak pressure testing of films prepared with varying numbers of buffer washes, laser temperature, and lasering time revealed no significant interaction between any of the 3 variables. As such, it was confirmed that proceeding with in vivo testing with the buffer wash, various lasering temperatures, and laser times would not affect the sealing performance of the films. Future investigation will involve characterization of additional materials that may be effective for sealing of internal wounds, as well as drug loading of agents that may hasten the healing process.

From previous research, it has been observed that neural summation can be observed from reaction time tasks. This is observed through race models, as proposed by J.O. Miller. These models are referred to as “race models” as different stimuli “race” to extract a response during tasks. The race model is augmented by the Race Model Inequality, which claims the probability that two simultaneous signals will have a faster reaction time than the summation of the probabilities of two individual signals. When this inequality expression is violated, it indicates neural summation is occurring. In another study, researchers studied how the location of visual stimuli influences neural summation with tactile information, observing the visual stimuli from different distances and a mirrored reflection condition. However, results of the mirror condition did not follow the other visual conditions, offering unique properties. The mirrored case is examined more closely in this project, attempting to answer if the presence of a mirrored representation of the hand will affect reaction time during timed tasks, suggesting the occurrence of neural summation, and suggesting that a mirrored reflection of self is interpreted as an independent channel of information. This was measured by evaluating participants’ response time while manipulating the presence of a reflection and checking if they violate the race model. However, the results of this study indicated that the presence of a mirror does not have an effect in reaction time and therefore did not present the occurrence of neural summation