Double-slot antennas on extended hemispherical dielectric lenses

An investigation of the coupling efficiencies to a gaussian-beam of a double-slot antenna on a hyperhemispherical lens is presented. It is shown that both lenses couple equally well to an appropriate gaussian beam (about 80 percent). The radiation patterns of both lenses with a double-slot antenna are computed using the ray-tracing method. The experimental radiation patterns are presented and show close agreement to the theoretically computed patterns

Broad spectrum proteomics analysis of the inferior colliculus following acute hydrogen sulfide exposure.

Acute exposure to high concentrations of H2S causes severe brain injury and long-term neurological disorders, but the mechanisms involved are not known. To better understand the cellular and molecular mechanisms involved in acute H2S-induced neurodegeneration we used a broad-spectrum proteomic analysis approach to identify key molecules and molecular pathways involved in the pathogenesis of acute H2S-induced neurotoxicity and neurodegeneration. Mice were subjected to acute inhalation exposure of up to750 ppm of H2S. H2S induced behavioral deficits and severe lesions including hemorrhage in the inferior colliculus (IC). The IC was microdissected for proteomic analysis. Tandem mass tags (TMT) liquid chromatography mass spectrometry (LC-MS/MS)-based quantitative proteomics was applied for protein identification and quantitation. LC-MS/MS identified 598, 562, and 546 altered proteomic changes at 2 h, and on days 2 and 4 post-H2S exposure, respectively. Of these, 77 proteomic changes were statistically significant at any of the 3 time points. Mass spectrometry data were subjected to Perseus 1.5.5.3 statistical analysis, and gene ontology heat map clustering. Expressions of several key molecules were verified to confirm H2S-dependent proteomics changes. Webgestalt pathway overrepresentation enrichment analysis with Panther engine revealed H2S exposure disrupted several biological processes including metabotropic glutamate receptor group 1 and inflammation mediated by chemokine and cytokine signaling pathways among others. Further analysis showed that energy metabolism, integrity of blood-brain barrier, hypoxic, and oxidative stress signaling pathways were also implicated. Collectively, this broad-spectrum proteomics data has provided important clues to follow up in future studies to further elucidate mechanisms of H2S-induced neurotoxicity

The Influence of Framing Effects on Public Opinion of Antibiotic use in Livestock

After years of debates and opposition from pharmaceutical companies, the Final rule of the Veterinary Feed Directive (VFD) went into effect in January 2017 requiring antibiotics used for both humans and animals for the purpose of growth promotion to be discontinued. This study sought to determine the effects framing content regarding antibiotic use in livestock and antibiotic resistance had on public opinion. Using a between-subjects experimental survey research design, 297 respondents indicated their perceptions of antibiotic use in livestock and the development of antibiotic resistant bacteria before being randomly assigned to one of three conditions. Each condition was a mock Twitter account framed differently based on findings from previous studies. After reading their assigned mock Twitter page, respondents indicated their trust of the information contained in the account, their information seeking behavior, demographics, and their support for antibiotic use in livestock. Using an ANCOVA, results indicated the frame influenced trust of information (F = 8.7, p \u3c .05) and information seeking behavior (F = 4.48, p = .01) while support was not significant (F = 2.7, p = .07). Results suggest the blame frame has the greatest influence on shaping public opinion of antibiotic use in livestock and the development of antibiotic resistance

A Sentiment and Content Analysis of Twitter Content Regarding the use of Antibiotics in Livestock

On January 1, 2017, the final rule of the Veterinary Feed Directive (VFD) was put into place requiring antibiotics approved for both humans and animals to be discontinued for growth promotion. This change was brought on by the role growth promoters in livestock production play in the development of antibiotic resistance. Antibiotic resistance increases the costs associated with human health care by increasing the length of stays in the hospital and requiring more intensive medical care for patients. The purpose of this study was to explore sentiment and characteristics of social media content and the characteristics of the key influencers whose opinions had the greatest amount of reach on social media in regard to antibiotic use in livestock and antibiotic resistance. Nuvi, a social media monitoring program, provided sentiment for each tweet and coded 64.8% of the content (n = 129) as negative compared to 38.2% (n = 76) humans coded as negative. The contrast between human coders and Nuvi indicates there could be discrepancies between how Nuvi codes content and the way a human might interpret the content. No key influencer discussed antibiotic use in livestock positively. Findings suggest agricultural communicators should not rely completely on the output from sentiment analysis programs to evaluate how the public discusses issues related to agriculture, particularly controversial issues. Further, agricultural communications practitioners should prioritize monitoring the content shared by key influencers in an effort to better understand the content being shared by the most influential users. Recommendations for future research are provided

A Content Analysis of Antibiotic use in Livestock in National U.S. Newspapers

The discovery of the antibiotic Aureomycin as a growth promotor for the livestock industry was viewed as revolutionary in 1950. The use of antibiotics as growth promoters in livestock, however, has been questioned by health professionals concerned with the role this use might play in the development of antibiotic resistant bacteria. As a public health issue, newspapers have covered this topic since its discovery. Media, such as newspapers, have used frames to discuss the topic over time as new discoveries have occurred, policy changes have been implemented, and food animal production has changed. The purpose of this study was to determine the frames and sources used by national U.S. newspapers when discussing the topic of antibiotic use in livestock and antibiotic resistance. A quantitative content analysis was conducted on three national U.S. newspapers from 1996 – 2017 and found three primary frames were used when discussing antibiotic use in livestock and antibiotic resistance. The content analysis also indicated that over 90% of the news articles contained a scientific source when communicating about this scientific topic. Based on the frames identified some readers are being ill-informed about this topic and could be using this information in their decision making without having all of the facts. Science communicators should prioritize the inclusion of scientific sources in their writing as they communicate about complex, controversial topics

Modeling Tropical Diversity in the Undergraduate Classroom: Novel Curriculum to Engage Students in Authentic Scientific Practicesum to Engage Students in Authentic Scientific Practices

A feature of science is its production of evidence-based explanations. Scientific models can both provide causal explanations and be predictive of natural phenomena. Modeling-based inquiry (MBI) is a pedagogical strategy that promotes students’ deep learning about phenomena via engagement in authentic scientific practices. Some university instructors have begun to facilitate MBI in their courses, notably those aimed at aspiring K–12 science educators who, per the Next Generation Science Standards, are encouraged to implement MBI. Yet exploration of curriculum and teaching with MBI in postsecondary environments is scarce. We detail a novel MBI curriculum implemented in a postsecondary ecology course that included students interested in future careers in education. The curriculum engages students in modeling why there is greater biological diversity in tropical than in temperate regions. This biological phenomenon continues to be of great interest to the scientific community. We briefly detail how the curriculum impacted students’ understanding of participation in aspects of scientific practices and their comfort with facilitating MBI