Poster #5006, Gisel Fregoso, UTEP BUILDing SCHOLARS
Poster Title: Increasing conductivity of Alginate ? Carbon nanotubes (CNTs) hydrogels through induced alignment
Abstract: The main contributing factor of imposing carbon nanotubes (CNTs) in hydrogels is the electrical conduction it can administer within the medium. Sufficient electrical conductivity was observed even within a dispersed medium of single- walled carbon nanotubes (SWCNTs) crosslinked with calcium chloride (CaCl2) in an alginate hydrogel 25 mm diameter disk, to operate a blue LED, requiring a forward voltage in range of 2.5 ? 3.7 V. Preliminary measurements of the completed circuit measured 300 mV across the Alginate ? SWCNTs hydrogel disk itself. A greater amount of conductivity has been observed laterally along the CNTs due to the anisotropic nature of the nanotubes allowing more current flux to trespass in that direction. In imposing an adequate magnetic field onto these CNTs, initial testing with a Halbach array of neodymium magnets demonstrated an ample amount to align the CNTs in an aqueous solution along the magnetic dipole moment. Therefore, by prompting multi-walled carbon nanotubes (MWCNTs) and SWCNTs to such an induced magnetic field for alignment forming semiconducting wires preceding crosslinking in an alginate solution, the conductivity across the hydrogel once crosslinked, can be exploited to increase charge permeating throughout the medium. Furthermore, direct application of an alginate ? CNTs hydrogel transitions to the potential formation of chemical sensors utilized to measure the resistance of the specified analyte indicated to quantify through added selectors in the molecular network.

Poster #5003, Daniel Gonzalez, CSULB BUILD
Poster Title: Effects of 3D Printing Build Parameters on Mechanical Properties of Dental Models Using DLP and SLA Technology
Abstract: The application of 3D printing technology has recently been applied to dentistry to reduce the time of manufacturing from several days to hours. Some common applications of 3D printing in dentistry include surgical guides, crowns, and night guards. Two common printing methods include stereolithography (SLA) and digital light processing (DLP). Research is lacking regarding how different build parameters affect the mechanical properties of 3D printed parts as dental models need to withstand the stress during surgery, in vivo implantation, and overnight use. The purpose of this study is to evaluate how build orientation affects the mechanical properties of 3D printed dental models by DLP and SLA printing methods. Six different printing orientations were analyzed by using a three-point flexural and tensile test on a Universal Testing Machine Shimadzu AGS-X. Maximum stress, percent elongation, elastic modulus, and flexural modulus were compared for all printing orientations. Layer thickness and post-curing methods were also compared for each of the six orientations. It was found that decreased layer thickness and post curing yielded a higher elastic and flexural modulus due to different degrees of cure. One benefit of a DLP printer is that UV light is used to polymerize a liquid acrylic resin layer by layer, decreasing print time compared to a single laser path for SLA. Understanding how the mechanical properties change form different printing parameters and post curing methods is important to be able to create a strong dental model with a necessary strength in the desired direction.

Poster #5004, Rahib Islam, XULA Project Pathways
Poster Title: Development of a Multifunctional Laser Hair Removal Patch
Abstract: Laser hair removal enables permanent hair removal and is among the most commonly practiced laser procedures in medicine. We hypothesize a two-layer patch will eliminate the problems with the current methodology by providing epidermal cooling, pain mitigation, plume control, and an indicator function. Study Design/Material and Methods: The hydrogel layer of the patch is a mixture of gelatin, water, and glycerol, which acts as an antifreeze agent and allows the patch to be stored in the freezer without freezing. The second layer is a film of plastic with ink particles printed on it and serves as the indicator. Heating of the particles causes a photothermal reaction to make an indentation on the sheet. Various adhesion tests were undertaken to ensure attachment of the two layers, and ?caliber super glue? proved optimal. Results: 30% glycerol, 70% water, and 3% gelatin proved to be optimal for handling of the gel and storage at -20C. Four different variants of the optimized patch were analyzed by the ELIZA spectrophotometer for absorption and transmission. These included the gel, the gel with plastic film, the gel with plastic film and ink particles, and the gel with plastic film, ink particles, and glue. Data showed that at a wavelength of 755 nm, the patch with the gel, plastic film, ink particles, and the glue has an absorbance of 0.1 while the patch with just the gel had an absorbance of 0.05. The spectrophotometer revealed that the absorbance increases by only 0.05, indicating that enough light can be transmitted to reach the skin and that only a minimal amount of light was lost between these two patches. Conclusions: Several parameters of the two-layer multifunctional laser patch have been optimized, and it was found that enough light could be transmitted through the gel with plastic film, ink particles, and glue to reach the skin.

Poster #5001, Don Napasindayao, CSULB BUILD
Poster Title: Development of Hand Torque Assessment Device with Adjustable Angle of Attack, Knob Size, and Resistance
Abstract: Hand manipulation is an important feature in human function. Properties such as grip force and hand torque are present in daily activities, such as opening prescription bottles and turning door knobs. Individuals who are suffering from hand impairment have reduced hand coordination between muscle force and external force, thus causing either slippage or crushing of a hand-held object. Our study aims to assess the differences for hand ability between healthy and hand-impaired groups, such as individuals with Multiple Sclerosis, and provide rehabilitation training using the developed hand function assessment system. The system consists of two devices: one for measuring grip and load force in lift-and-hold tasks and another for measuring the hand torque in turning tasks. This work focuses on the development of the second device for hand torque evaluation. The device consists of a DC motor with an optical encoder, a torque sensor, and interchangeable knobs to measure hand torque and the angle of twist at different resistance levels. The interchangeable knobs are available at 1, 2, and 3-inch diameters. Furthermore, the device?s design allows for adjustment of the angle of attack, which is the direction for which the user turns the knob. The angle of attack can be adjusted between 0 and 90 degrees with an increment of 22.5 degrees. A graphic user interface was developed in LabView to allow an operator to set the device parameters and record the data for further analysis. A preliminary user study will be conducted in order to test the functionality of the device. This will then be followed by data collection with healthy, young adults and individuals with hand impairment.