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Purpose: To demonstrate the utility of high-resolution micro-computed tomography ( μ CT ) for determining ground-truth size and shape properties of calcium grains for evaluation of detection performance in breast CT (bCT). Approach: Calcium carbonate grains ( ∼ 200    μ m ) were suspended in 1% agar solution to emulate microcalcifications ( μ Calcs ) within a fibroglandular tissue background. Ground-truth imaging was performed on a commercial μ CT scanner and was used for assessing calcium-grain size and shape, and for generating μ Calc signal profiles. Calcium grains were placed within a realistic breast-shaped phantom and imaged on a prototype bCT system at 3- and 6-mGy mean glandular dose (MGD) levels, and the non-prewhitening detectability was assessed. Additionally, the μ CT -derived signal profiles were used in conjunction with the bCT system characterization (MTF and NPS) to obtain predictions of bCT detectability. Results: Estimated detectability of the calcium grains on the bCT system ranged from 2.5 to 10.6 for 3 mGy and from 3.8 to 15.3 for 6 mGy with large fractions of the grains meeting the Rose criterion for visibility. Segmentation of μ CT images based on morphological operations produced accurate results in terms of segmentation boundaries and segmented region size. A regression model linking bCT detectability to μ Calc parameters indicated significant effects of μ Calc size and vertical position within the breast phantom. Detectability using μ CT -derived detection templates and bCT statistical properties (MTF and NPS) were in good correspondence with those measured directly from bCT ( R 2 > 0.88 ). Conclusions: Parameters derived from μ CT ground-truth data were shown to produce useful characterizations of detectability when compared to estimates derived directly from bCT. Signal profiles derived from μ CT imaging can be used in conjunction with measured or hypothesized statistical properties to evaluate the performance of a system, or system component, that may not currently be available.

The design and testing of a prototype Multi-X-ray-source Array (MXA) for digital breast tomosynthesis is reported. The MXA is comprised of an array of tungsten filament cathodes with focus cup grid-controlled modulation and a common rotating anode housed in a single vacuum envelope. Prototypes consisting of arrays of three-source elements and eleven-source-elements were fabricated and evaluated. The prototype sources demonstrated focal spot sizes of 0.3 mm at 45 kV with 50 mA. Measured x-ray spectra were consistent with the molybdenum anode employed, and the tube output (air kerma) was between 0.6 mGy/100 mAs at 20 kV and 17 mGy/100 mAs at 45 kV with a distance of 100 cm. HVL measurements ranged from 0.5 mm Al at 30 kV to 0.8 mm Al at 45 kV, and x-ray pulse widths were varied from 20 ms to 110 ms at operating frequencies ultimately to be limited by source turn-on/off times of ∼1 ms. Initial results of reconstructed tomographic data are presented.

The purpose of this study was to compare various multisource configurations applied to cone beam CT (CBCT) using phantom imaging and Monte Carlo simulations. Image quality, scatter, and dose were evaluated in both overlapping (large cone angle) and collimated (small cone angle) configurations for CBCT. Four x-ray tube configurations were considered: traditional one source, three source overlapping, six source overlapping, and six source collimated. Image quality was evaluated on a prototype breast CT system using the following five phantoms: a Defrise phantom, a previously reported CBCT QA phantom (Corgi), a polyethylene cylinder, and two anthropomorphic phantoms (hand and knee). Scatter contamination and radiation dose were evaluated using Monte Carlo simulations of a voxelized polyethylene cylinder. The modulation of the Defrise phantom disks on average was 2.7X greater for the six source collimated configuration than the six source overlapping configuration. The data lost from cone beam artifact (spatial domain) and the null cone (frequency domain) in the overlapping configuration were completely recovered using the collimated configuration. The maximum scatter-to-primary ratio (SPR) for the overlapping configuration was 0.81 and the maximum SPR for the collimated configuration was 0.26. The average dose and maximum dose was 4X less in the collimated six source configuration when compared with the overlapping configurations. The maximum dose for the overlapping configurations (one, three & six) remained constant, but the average dose for the multisource (three & six source) overlapping configurations increased 25% when compared to the one source configuration. Use of a collimated multisource x-ray tube configuration was shown to provide significant improvements in image quality throughout the cone-beam geometry field-of-view, reduction in scatter contamination, and more efficient use of dose in comparison to both the traditional CBCT geometry with a single source and the overlapping multisource configurations.

Given declining public trust in mainstream media outlets, late-night comedians are increasingly relied upon as trusted sources of political information. Connections with late-night hosts have taken on a personalized, psychological dimension and have even become a part of media users' expression of social group identity. Understanding this dynamic, the research presents a thematic textual analysis of the twelve-plus hours of conversation and comic banter between Stephen Colbert, Jimmy Fallon, Jimmy Kimmel, Seth Meyers, and John Oliver that aired across the twelve-episode run of the Fall 2023 podcast, Strike Force Five. Connecting with viewers during the 2023 Writers Guild of America (WGA) strike, the podcast presents a personalized view of the life of these five comedians as they dialogue about their families, the early days of their comedy careers, the history of late-night comedy programming, and their unique public friendship despite being cast by the media as competitors in the late-night ratings war. Analyzing the reach and impact of the Strike Force Five podcast is an important part of furthering an understanding of the influence of late-night comedy and political satire on our political life and popular culture. [ABSTRACT FROM AUTHOR]

The research compares the ironically anti-Semitic Sacha Baron Cohen character of Borat Sagdiyev from the 2020 Borat Subsequent Moviefilm with Cohen's 2019 (See CR25) uncharacteristic out-of-character public advocacy work with the Anti-Defamation League in an effort to stop the spread of hate online via social media. Discussing the use of irony and antiphrasis to promote a greater understanding of society's tolerance of anti-Semitism and indifference to hate, Cohen's comic work is contrasted with the use of his public celebrity to spread the same message against hate and indifference. The manuscript suggests that despite backlash to Borat Subsequent Moviefilm, the 2020 comic effort offers an impactful antidote to the rapid spread of hate and anti-Semitism online via social media and successfully advances Cohen's use of extreme and exaggerated characters to ironically advocate for greater tolerance. In a political environment ripe with the spread of misinformation and the rise of hate speech, Cohen's ironic characters and his celebrity activism both stand as important contributions to our public discourse., Author(s): Amy B. Becker [sup.1] Author Affiliations: (1) grid.259262.8, 0000 0001 1014 2318, Department of Communication, Loyola University Maryland, , 4501 N. Charles Street, 21210, Baltimore, MD, USA Known for [...]

Introduction: A youth’s emergency department (ED) visit for suicidal behaviors or ideation provides an opportunity to counsel families about securing medications and firearms (i.e., lethal means counseling).Methods: In this quality improvement project drawing on the Counseling on Access to Lethal Means (CALM) model, we trained 16 psychiatric emergency clinicians to provide lethal means counseling with parents of patients under age 18 receiving care for suicidality and discharged home from a large children’s hospital. Through chart reviews and follow-up interviews of parents who received the counseling, we examined what parents recalled, their reactions to the counseling session, and actions taken after discharge.Results: Between March and July 2014, staff counseled 209 of the 236 (89%) parents of eligible patients. We conducted follow-up interviews with 114 parents, or 55% of those receiving the intervention; 48% of those eligible. Parents had favorable impressions of the counseling and good recall of the main messages. Among the parents contacted at follow up, 76% reported all medications in the home were locked as compared to fewer than 10% at the time of the visit. All who had indicated there were guns in the home at the time of the visit reported at follow up that all were currently locked, compared to 67% reporting this at the time of the visit.Conclusion: Though a small project in just one hospital, our findings demonstrate the feasibility of adding a counseling protocol to the discharge process within a pediatric psychiatric emergency service. Our positive findings suggest that further study, including a randomized control trial in more facilities, is warranted.

The research (N = 265) considers the effect of exposure to personalized political comedy on the gun control debate on message discounting, perceived informativeness, and message elaboration. Results show that viewers are less likely to engage in message discounting, more likely to engage in message elaboration, and more likely to rate personalized political comedy as informative when compared against exposure to a standard late-night monologue. Importantly, the findings show that personalized political comedy content has greater message engagement effects among those with lower affinity for entertaining news, suggesting that personalized political comedy may help to expand issue engagement and audiences. [ABSTRACT FROM AUTHOR]

The healthcare sector generates approximately 10% of the total carbon emissions in the United States. Radiology is thought to be a top contributor to the healthcare carbon footprint due to high energy-consuming devices and waste from interventional procedures. In this article, we provide a background on Radiology's environmental impact, describe why hospitals should add sustainability as a quality measure, and give a framework for radiologists to reduce the carbon footprint through quality improvement and collaboration. [ABSTRACT FROM AUTHOR]

As with public opinion on other policy issues, attitudes toward transgender rights are partly driven by "group-centric" reasoning. Those with more positive feelings toward transgender people are more likely to support policies that protect their rights. But linking group affect with policies impacting members of that group requires some knowledge and understanding of politics, which not all citizens possess to the same extent. In this research note, we demonstrate that political awareness moderates the relationship between affect toward transgender people and support for their civil rights. ANES data from 2016 and 2020 show that more politically sophisticated respondents were more likely to connect their views of transgender people with policies that protect their rights. These results suggest that group-centric thinking is most prevalent among the most, not least, politically aware. [ABSTRACT FROM AUTHOR]