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Title: Engineering Escherichia coli to produce and secrete colicins for rapid and selective biofilm cell killing
Creator: Jin, Xing, An, Sungjun, Kightlinger, Weston, Zhou, Jiacheng, Hong, Seok Hoon
Date: 2021
Description: Bacterial biofilms are associated with chronic infectious diseases and are highly resistant to conventional antibiotics. Antimicrobial...
Show moreBacterial biofilms are associated with chronic infectious diseases and are highly resistant to conventional antibiotics. Antimicrobial bacteriocins are alternatives to conventional antibiotics and are characterized by unique cell-killing mechanisms, including pore formation on cell membranes, nuclease activity, and cell wall synthesis inhibition. Here, we used cell-free protein synthesis to rapidly evaluate the antibiofilm activities of colicins E1, E2, and E3. We found that E2 (with DNase activity) most effectively killed target biofilm cells (i.e., the K361 strain) while leaving nontargeted biofilms intact. We then engineered probiotic Escherichia coli microorganisms with genetic circuits to controllably synthesize and secrete colicin E2, which successfully inhibited biofilms and killed preformed indicator biofilms. Our findings suggest that colicins rapidly and selectively kill target biofilm cells in multispecies biofilms and demonstrate the potential of using microorganisms engineered to produce antimicrobial colicin proteins as live therapeutic strategies to treat biofilm-associated infections.
Sponsorship: NIH-R15AI130988
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Title: Editorial, "Cell-Free Synthetic Biology": Synthetic Biology Meets Cell-Free Protein Synthesis
Creator: Hong, Seok Hoon
Date: 2019
Publisher: MDPI
Description: Sponsorship: NIH R15AI130988

Title: Incorporation of non-standard amino acids into proteins: challenges, recent achievements, and emerging applications
Creator: Jin, Xing, Park Oh-Jin, Hong, Seok Hoon
Date: 2019
Description: The natural genetic code only allows for 20 standard amino acids in protein translation, but genetic code reprogramming enables the...
Show moreThe natural genetic code only allows for 20 standard amino acids in protein translation, but genetic code reprogramming enables the incorporation of non-standard amino acids (NSAAs). Proteins containing NSAAs provide enhanced or novel properties and open diverse applications. With increased attention to the recent advancements in synthetic biology, various improved and novel methods have been developed to incorporate single and multiple distinct NSAAs into proteins. However, various challenges remain in regard to NSAA incorporation, such as low yield and misincorporation. In this review, we summarize the recent efforts to improve NSAA incorporation by utilizing orthogonal translational system optimization, cell-free protein synthesis, genomically recoded organisms, artificial codon boxes, quadruplet codons, and orthogonal ribosomes, before closing with a discussion of the emerging applications of NSAA incorporation.
Sponsorship: NIH R15AI130988
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Title: Undecanoic Acid, Lauric Acid, and N-Tridecanoic Acid Inhibit Escherichia coli Persistence and Biofilm Formation
Creator: Jin, Xing, Zhou, Jiacheng, Richey, Gabriella, Wang, Mengya, Hong, Sung Min Choi, Hong, Seok Hoon
Date: 2021
Description: Persister cell formation and biofilms of pathogens are extensively involved in the development of chronic infectious diseases. Eradicating...
Show morePersister cell formation and biofilms of pathogens are extensively involved in the development of chronic infectious diseases. Eradicating persister cells is challenging, owing to their tolerance to conventional antibiotics, which cannot kill cells in a metabolically dormant state. A high frequency of persisters in biofilms makes inactivating biofilm cells more difficult, because the biofilm matrix inhibits antibiotic penetration. Fatty acids may be promising candidates as antipersister or antibiofilm agents, because some fatty acids exhibit antimicrobial effects. We previously reported that fatty acid ethyl esters effectively inhibit Escherichia coli persister formation by regulating an antitoxin. In this study, we screened a fatty acid library consisting of 65 different fatty acid molecules for altered persister formation. We found that undecanoic acid, lauric acid, and N-tridecanoic acid inhibited E. coli BW25113 persister cell formation by 25-, 58-, and 44-fold, respectively. Similarly, these fatty acids repressed persisters of enterohemorrhagic E. coli EDL933. These fatty acids were all medium-chain saturated forms. Furthermore, the fatty acids repressed Enterohemorrhagic E. coli (EHEC) biofilm formation (for example, by 8-fold for lauric acid) without having antimicrobial activity. This study demonstrates that medium-chain saturated fatty acids can serve as antipersister and antibiofilm agents that may be applied to treat bacterial infections.
Sponsorship: NIH-R15AI130988; NSF REU-1757989
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Title: Priming Movie Product Placements: New Insights from a Cross-National Case Study
Creator: Balasubramanian,Siva K, Gistri, Giacomo
Date: 44354, 44327
Publisher: Taylor & Francis
Description: The paucity of research on priming product placements and insights from practitioners (Study 1) motivated our investigation into how and when...
Show moreThe paucity of research on priming product placements and insights from practitioners (Study 1) motivated our investigation into how and when priming works in movie placements. Study 2 explores the impact of media priming (a media story announcing a movie placement before the movie’s release) and ad priming (a similar ad announcement) on recall through contrasts with no priming (control). US students watched a movie in a theatre after such priming for a subtle or a prominent placement. When compared to no priming, both media priming and ad priming enhanced recall for the subtle placement; no difference in recall performance emerged between no priming and either type of priming for the prominent placement. Contrast tests comparing media priming and ad priming indicated no differences in recall for either subtle or prominent placement. Study 3 replicated these recall findings with Italian moviegoers, and supported additional hypotheses and propositions for brand attitude. For the subtle (prominent) placement, attitude did not change (decreased) when comparing either media priming or ad priming with no priming. Contrast tests comparing media priming and ad priming indicated no differences in attitude outcomes, for either subtle or prominent placement. Using no priming as a baseline for comparison, the converging conclusion is that any type of priming improves (does not change) recall and does not change (worsens) attitude for subtle (prominent) placements. Overall, results do not support priming for prominent placements; selective use of any type of priming for subtle placements appears appropriate to improve recall outcomes.
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Collection: International Journal of Advertising

Title: Some Paradoxes of Whistleblowing
Creator: Davis, Michael
Date: 2006, 1996
Publisher: Philosophy Documentation Center
Description: By "paradox" I mean an apparent- and in this case, real-inconsistency between theory (our systematic understanding of whistleblowing) and the...
Show moreBy "paradox" I mean an apparent- and in this case, real-inconsistency between theory (our systematic understanding of whistleblowing) and the facts (what we actually know, or think we know, about whistleblowing). What concerns me is not a few anomalies, the exceptions that test a rule, but a flood of exceptions that seem to swamp the rule. This paper has four parts. The first states the standard theory of whistleblowing. The second argues that the standard theory is paradoxical, that it is inconsistent with what we know about whistleblowers. The third part sketches what seems to me a less paradoxical theory of whistleblowing. The fourth tests this new theory against one classic case of whistleblowing, Roger Boisjoly's testimony before the presidential commission investigating the Challenger disaster (the "Rogers Commission"). I use that case because the chief facts are both uncontroversial enough and well-known enough to make detailed exposition unnecessary. For the same reasons, I also use that case to illustrate various claims about whistleblowing throughout the paper.
Business and Professional Ethics Journal, Vo. 15, No.1. pp.3-19.
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Title: “Broader Impacts” or “Responsible Research and Innovation”? A Comparison of Two Criteria for Funding Research in Science and Engineering
Creator: Davis, Michael, Laas, Kelly
Date: 2013-10, 2013-10
Publisher: Springer
Description: Our subject is how the experience of Americans with a certain funding criterion, “broader impacts” (and some similar criteria) may help in...
Show moreOur subject is how the experience of Americans with a certain funding criterion, “broader impacts” (and some similar criteria) may help in efforts to turn the European concept of Responsible Research and Innovation (RRI) into a useful guide to funding Europe’s scientific and technical research. We believe this comparison may also be as enlightening for Americans concerned with revising research policy. We have organized our report around René Von Schomberg’s definition of RRI, since it seems both to cover what the European research group to which we belong is interested in and to be the only widely accepted definition of RRI. According to Von Schomberg, RRI: “… is a transparent, interactive process by which societal actors and innovators become mutually responsive to each other with a view to the (ethical) acceptability, sustainability and societal desirability of the innovation process and its marketable products (in order to allow a proper embedding of scientific and technological advances in our society).” While RRI seeks fundamental changes in the way research is conducted, Broader Impacts is more concerned with more peripheral aspects of research: widening participation of disadvantaged groups, recruiting the next generation of scientists, increasing the speed with which results are used, and so on. Nevertheless, an examination of the broadening of funding criteria over the last four decades suggests that National Science Foundation has been moving in the direction of RRI.
Sponsorship: European Community’s Seventh Framework Programme grant number 321400.
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Title: Research in Architectural Education: Theory and Practice of Visual Training
Creator: Jones, Kristin
Date: 2016, 12/12/2016
Collection: Enquiry

Title: From positivism to conventionalism: Comte, Renouvier, and Poincaré
Creator: Schmaus, Warren
Date: 2019, 2019
Publisher: Elsevier

Title: A Gröbner Basis Database
Creator: Mojsilović, Jelena
Date: 2022

Title: Stephen Fienberg's influence on algebraic statistics, Special Volume in honor of memory of S.E.Fienberg
Creator: Petrović, Sonja, Slavkovic, Aleksandra, Yoshida, Ruriko
Date: 2019, 2019-04-12
Description: Stephen (Steve) E. Fienberg (1942-2016) was an eminent statistician, whose impact on research, education and the practice of statistics, and...
Show moreStephen (Steve) E. Fienberg (1942-2016) was an eminent statistician, whose impact on research, education and the practice of statistics, and many other fields is astonishing in its breadth. He was a visionary when it came to linking many different areas to address real scientific issues. He professed the importance of statistics in many disciplines, but recognized that true interdisciplinary work requires joining of the expertise across different areas, and it is in this spirit that he helped steer algebraic statistics toward becoming a thriving subject. Many of his favorite topics in the area are covered in this special issue. We are grateful to all authors for contributing to this volume to honor him and his influence on the field. During the preparation of this issue, we learned about the tragic killing of his widow, Joyce Fienberg, during the Tree of Life Synagogue massacre in Pittsburgh, PA on October 27, 2018. This issue is dedicated to their memory.
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Collection: Journal of Algebraic Statistics