Identification of Traumatic Bone Marrow Oedema: The Pearls and Pitfalls of Dual-Energy CT (DECT)

Dual-energy computed tomography (DECT) has been reported to successfully identify bone marrow oedema (BME) in various traumatic settings. DECT has multiple strengths, including the availability of both a 3D view of the anatomical area studied and of high-resolution dual energy specific maps super-imposed onto conventional grayscale morphological images. Windowing can be used to enhance the visualization of BME by increasing the level of the super-imposed images. Conversely, by decreasing the level of the super-imposition of color-coded images, it is possible to progressively enhance the visualization of fine anatomical details, which is useful for diagnosing associated imaging findings. Importantly, bone sclerosis may represent an important pitfall for DECT, potentially generating both false positive and false negative findings by locally altering CT numbers. The aim of this paper was to evaluate the strengths and limitations of DECT in accurately detecting traumatic BME, by considering practical approaches to imaging at several anatomical sites.

Pictures in politics: a visual social semiotics analysis of federal politicians on Instagram

This major research paper (MRP) examines the visual social semiotics of Canadian politicians’ Instagram accounts and their followers’ responses. As a qualitative study, it seeks to address the following questions: From the coded images in the data collection, which qualities do the Instagram followers prefer? From the coded images in the data collection, which qualities do the Instagram followers prefer the least? What do these qualities reveal about the political actors in the data collection? To answer these questions, I coded the most liked and least liked Instagram postings between April 1, 2014 and March 31, 2015 from two of Canada’s federal party leaders, Prime Minister Stephen Harper and Liberal leader Justin Trudeau. These images were coded through a visual social semiotics analysis under the following categories in my codebook: community outreach, competence, empathy, excitement, ideology, personal, symbols of nationalism, celebrity, and miscellaneous. This codebook was constructed from a literature review encompassing the public’s values of politicians in traditional media. The findings of this MRP expand on visual social semiotic theory in the social media context and build on research about audience perceptions of politicians. The results suggest that photo composition and the presentations of values in an image are important considerations for politicians. Based on the findings, this study is relevant to how professional communicators can construct a persuasive image and story in the political context on a social media platform.

Pictures in politics: a visual social semiotics analysis of federal politicians on Instagram

This major research paper (MRP) examines the visual social semiotics of Canadian politicians’ Instagram accounts and their followers’ responses. As a qualitative study, it seeks to address the following questions: From the coded images in the data collection, which qualities do the Instagram followers prefer? From the coded images in the data collection, which qualities do the Instagram followers prefer the least? What do these qualities reveal about the political actors in the data collection? To answer these questions, I coded the most liked and least liked Instagram postings between April 1, 2014 and March 31, 2015 from two of Canada’s federal party leaders, Prime Minister Stephen Harper and Liberal leader Justin Trudeau. These images were coded through a visual social semiotics analysis under the following categories in my codebook: community outreach, competence, empathy, excitement, ideology, personal, symbols of nationalism, celebrity, and miscellaneous. This codebook was constructed from a literature review encompassing the public’s values of politicians in traditional media. The findings of this MRP expand on visual social semiotic theory in the social media context and build on research about audience perceptions of politicians. The results suggest that photo composition and the presentations of values in an image are important considerations for politicians. Based on the findings, this study is relevant to how professional communicators can construct a persuasive image and story in the political context on a social media platform.

A feasibility study on the application of separable coded masks to X-ray fluorescence imaging

The coded images acquired by the XRF imaging system can be reconstructed with a neural network and an iterative algorithm.

Semi-quantitative CT imaging in improving visualization of faint ground glass opacities seen in early/mild coronavirus (covid-19) cases

Background Chest CT is an essential and simple diagnostic method for early detection of pulmonary changes in COVID-19 patients. Semi-quantitative technique depending on both visual and color coded images helps to improve the early detection of COVID-19 chest affection and thus help to control spread of infection. Results From first of May to July 15, 2020, 30 patients in Cairo, Egypt who have positive RT-PCR tests and positive pulmonary manifestation were included in our study, 26 patients (86.6%) with faint ground glass opacities were detected by both visual and color coded images, while in 4 patients (13.3%) were only visualized by color coded images and confirmed by CT density assessment. Conclusion The combined use of visual and color coded images enhance and improve the early detection of faint ground glass opacities seen in early COVID-19 affection.

Tactile perception of randomly rough surfaces

Most everyday surfaces are randomly rough and self-similar on sufficiently small scales. We investigated the tactile perception of randomly rough surfaces using 3D-printed samples, where the topographic structure and the statistical properties of scale-dependent roughness were varied independently. We found that the tactile perception of similarity between surfaces was dominated by the statistical micro-scale roughness rather than by their topographic resemblance. Participants were able to notice differences in the Hurst roughness exponent of 0.2, or a difference in surface curvature of 0.8 $$\hbox {mm}^{-1}$$ mm - 1 for surfaces with curvatures between 1 and 3 $$\hbox {mm}^{-1}$$ mm - 1 . In contrast, visual perception of similarity between color-coded images of the surface height was dominated by their topographic resemblance. We conclude that vibration cues from roughness at the length scale of the finger ridge distance distract the participants from including the topography into the judgement of similarity. The interaction between surface asperities and fingertip skin led to higher friction for higher micro-scale roughness. Individual friction data allowed us to construct a psychometric curve which relates similarity decisions to differences in friction. Participants noticed differences in the friction coefficient as small as 0.035 for samples with friction coefficients between 0.34 and 0.45.

“Roll with us”: Instagram Images of Backwoods Cigarillo Blunts (Preprint)

BACKGROUND Instagram, one of the most popular social media platforms among youth, offers a unique opportunity to examine blunts—partially or fully hollowed out large cigars, little cigars, and cigarillos that are filled with marijuana. Cigarillo brands like Backwoods (Imperial Tobacco Group Brands LLC) have product features that facilitate blunt-making, including a variety of brand-specific flavors that enhance the smoking experience (e.g., honey, dark stout). Backwoods has a growing online presence with a user-friendly website and an active Instagram account with over 30,000 followers. OBJECTIVE The present study examined the extent to which Backwoods cigarillo-related posts to Instagram showed blunt-making. Instagram offers a unique opportunity to examine blunt-making as Instagram accounts will contain images reflective of organic behavior occurring without the prime of a researcher. METHODS Inclusion criteria for this study included an Instagram post with the hashtag “#backwoods”. Rules were established to content analyze posts. Categories included Type of post (i.e., photo or video or both); Blunt-related hashtags (i.e., the corresponding caption to the post contained hashtag(s) like #blunts, #cannabis, #weed that were identified in previous social media research); Rolling blunts (i.e., the post contained an image of an individual(s) rolling a Backwoods cigarillo visibly containing marijuana); Smoking blunts (i.e., the post contained an image of an individual(s) blowing smoke or holding a lit blunt. We coded images for Flavor reference, where a code of 1 showed a Backwoods cigarillo pack with a brand-specific flavor (e.g., honey, dark stout, Russian crème) visible in the blunt-related image and a code of 0 indicated that it was not visible anywhere in the image. RESULTS Among all posts (n = 1,206), 871 (72.2%) were Blunt-related hashtags. A total of 125 (10.4%) images were coded Smoking blunts and 25 (2.1%) were coded Rolling blunts (i.e., Backwoods cigarillo explicitly used to roll blunts. Among blunt images, 434/843 (51.5%) were coded Flavor (i.e., a Backwoods pack with a brand-specific flavor was visible). CONCLUSIONS Most Backwoods cigarillo-related Instagram images were blunt-related and these blunt-related images showed Backwoods packages indicating flavor preference. Continued monitoring and surveillance of blunt-related posts on Instagram is needed to inform policies and interventions that reduce the risk that youth may experiment with blunts. Specific policies could include restrictions on product features (e.g., flavors, perforated lines, attractive resealable foil pouches, sold as singles) that facilitate blunt-making. CLINICALTRIAL N/A

A NEW BLACK BOX METHODOLOGY: THE CHALLENGES AND OPPORTUNITIES OF INTERROGATING THE MODERATION OF IMAGES DEPICTING WOMEN’S BODIES ON INSTAGRAM

The black box around online platforms’ internal governance practices makes it difficult for users to trust that their expression is moderated in ways that are free from arbitrariness and bias. This paper proposes a black box methodology for examining content moderation in practice when only parts of a platform’s regulatory system are visible from the outside. The proposed methodology, which uses content analysis and innovative digital methods to investigate how discrete inputs (i.e. images) produce certain outputs (i.e. whether an image is removed or not removed), is explained through a topical case study into whether like images of Underweight, Mid-Range and Overweight women’s bodies are moderated alike on Instagram. Overall, results show a trend of inconsistent moderation: specifically, up to 22% of 4,994 coded images were removed by Instagram or by the user and are therefore potentially false positives. Moreover, the odds of removal for Underweight, Mid-Range and Overweight images differ. These results suggest that concerns around the risk of arbitrariness and bias on Instagram, and, indeed, ongoing distrust of the platform among users, might not be unfounded. In outlining the proposed methodology, this paper evaluates the methodological, legal and ethical challenges to studying Instagram, many of which are due to the significant lack of transparency around platform governance more broadly. By evaluating these challenges, we can better assess the efficacy of using black box analytics and digital methods to examine important questions around content moderation at scale.