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Nearly half of people who die by suicide see a health care provider in the month before their death. With the release of new care guidelines, detection of suicidal patients will likely increase. Providers need access to suicide-specific resources that can be used as part of immediate, brief interventions with a suicidal patient. Web-based suicide prevention resources have the potential to address this need. This study aimed to describe the development of the NowMattersNow.org website as a resource for individuals with suicidal thoughts and to evaluate the utility of the site via user experience surveys. NowMattersNow.org is an online video-based free public resource that provides evidence-based teachings, examples, and resources for managing suicidal thoughts and intense emotions focused largely around skills from dialectical behavior therapy. Developed with assistance from mental health consumers, it is intended to address gaps in access to services for suicidal patients in health care systems. Visitors stay an average of a minute and a half on the website. From March 2015 to December 2017, a user experience survey measured self-reported changes on a 1 (not at all) to 5 (completely overwhelming) scale regarding intensity of suicidal thoughts and negative emotions while on the website. Longitudinal regression analyses using generalized estimating equations evaluated the magnitude and statistical significance of user-reported changes in suicidal ideation and negative emotion. In secondary analyses, user-reported changes specific to subgroups, including men aged 36 to 64 years, mental health care providers, and other health care providers were evaluated. During the period of analysis, there were 138,386 unique website visitors. We analyzed surveys (N=3670) collected during that time. Subsamples included men aged 36 to 64 years (n=512), mental health providers (n=460), and other health care providers (n=308). A total of 28% (1028/3670) of survey completers rated their suicidal thoughts as a 5 or \"completely overwhelming\" when they entered the website. We observed significant reductions in self-reported intensity of suicidal thoughts (-0.21, P<.001) and negative emotions (-0.32, P<.001), including decreases for users with the most severe suicidal thoughts (-6.4%, P<.001), most severe negative emotions (-10.9%, P<.001), and for middle-aged men (-0.13, P<001). Results remained significant after controlling for length of visit to website (before the survey) and technology type (mobile, desktop, and tablet). Survey respondents reported measurable reductions in intensity of suicidal thoughts and emotions, including those rating their suicidal thoughts as completely or almost completely overwhelming and among middle-aged men. Although results from this user-experience survey administered at one point in time to a convenience sample of users must be interpreted with caution, results provide preliminary support for the potential effectiveness of the NowMattersNow.org website as a tool for short-term management of suicidal thoughts and negative emotions.

In this thesis, we explore the way different cuts of diamonds affect the light that interacts with them. While some have analyzed diamond shape mathematically, no currently published research has used simulation to determine how light interacts with diamond models. We used forward ray tracing to simulate photons traveling through the scene using reflection and refraction. We created visualizations to show both single photons traveling through the scene and many photons in a single scene. Different colors were used to differentiate photon wavelengths or to show the number of bounces a photon had taken along its path. Small normal lines were used to show when the photons had hit a diamond face or a wall, which was useful both for debugging purposes on individual hits and when looking at the distribution of many photon hits in a scene. In order to be able to view more photon paths in a scene without them blocking each other, We also created visualizations with low alpha photon paths. We used forward raytracing to recursively send photons through a scene containing a diamond. The Sellmeier equation was used to determine if a photon was absorbed, and then the Fresnel equation determined if the photon was reflected or refracted. If the photon reflected, we used the reflection equation, and if it refracted, we used Snell’s Law to determine the refraction angle. We found that the two round brilliant diamond models we used performed significantly better than the other types of models at sending photons out of the top half of the model. The princess cut model also did much better than the sphere, which was used as an example of how much light would be sent out of the top if no effort went into designing a diamond to send light out of the top. We used the angle at which the photons leave the diamond and the angle of the faces that they leave from to determine which diamond models perform the best.