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Electronic Supporting Data: Tetrachloroanthracene Walled Glycoluril Dimer Undergoes Self-Association and 1:1, 2:2, and 1:3 Host•Guest Binding
No full textWe report the design, synthesis and characterization of a tetrachloroanthracene walled methylene bridged glycoluril dimer (H1). According to 1H NMR spectroscopy and symmetry considerations we formulate H1 as a C2v-symmetric monomer in DMSO but it exists as a C2h-symmetric dimer (H1•H1) in water. The H1•H1 dimer persists below 25 uM in water and displays high thermodynamic stability (Ks ≥ 1.8 x 106 M-1). H1•H1 is also stable up to 70 ˚C in water. We investigated the binding of H1 with a panel of five dyes by isothermal titration calorimetry and 1H NMR spectroscopy and found that H1 engages with dyes with several different stoichiometries of binding. For example, NMeAc and Berb are capable of causing the dissociation of H1•H1 resulting in the formation of the 1:1 intracavity dye complexes H1•NMeAc and H1•Berb. In contrast, Rh6G and ThT do not dissociate the H1•H1 dimer and instead stack on the exterior of the dimer to form Rh6G•H1•H1•Rh6G and ThT•H1•H1•ThT, respectively. Finally, 3 equivalents of NDI+ causes dissociation of H1•H1 and binds both intracavity and on the exterior to form the H1•(NDI+)3 complex.We thank the National Science Foundation (CHE-1807486) for past financial support. We thank the National Institute of General Medical Sciences of the National Institutes of Health (R35GM153362) for current financial support of this project
The cruciferous vegetable Brassica oleracea L. var. acephala, (Kale) protects against pro-inflammatory- lipopolysaccharide formation, translocation, and endotoxicity.
No full textCruciferous vegetables have been widely studied for cancer prevention and cardiovascular health. Broccoli is a cruciferous vegetable whose phytochemistry and physiological effects have been most extensively studied. Kale is often on the list of ‘most healthy foods,’ but there is a paucity of scientific data on it. Easily cultivated with resistance to extreme weather, kale is rich in phytochemicals and micronutrients. Compared to other Brassica, including broccoli, arugula, and cabbage, kale has the highest density of sulforaphane, lutein, zeaxanthin, β-carotene, quercetin, and minerals (Zn, K, P). The gut microbiota influences host phenotype through direct contact with intestinal cells or indirectly via bacterial metabolites. Lipopolysaccharide (LPS) is one of the most potent activators of innate immune signaling, is a causal or complicating factor in several diseases, and is an important mediator of the microbiome’s influence on host physiology. The structure, chemical properties, and immunogenicity of LPS vary depending on the specific gut bacterial species that produce it. Pro-inflammatory LPS (P-LPS) activates the innate immune system, leading to inflammatory responses. In contrast, immunosuppressive or anti-inflammatory LPS (A-LPS) is not a ligand for Toll-like receptor 4 (TLR4) and therefore does not trigger immune signaling. Host-mediated inflammation, whether from the diet, a pathogen, chemical induction, or deficiency in immunity, favors the growth of aerobic bacterial taxa, e.g., Enterobacteriaceae, the main producers of P-LPS. The P-LPS is a highly immunogenic antigen that further exacerbates inflammation and is detrimental to gut barrier function.
The goal of this study was to determine the protective impacts of kale supplementation as a functional food against diet-induced fat accumulation, insulin resistance, and inflammation. In two studies in C57BL6 mice, we found that whole ‘curly green kale’ is protective against systemic low-grade inflammation induced by a high fat (HF) diet and acute inflammation induced chemically by dextran sulfate sodium (DSS). The second goal of the study was to determine mechanisms by which kale protects against the formation, translocation, and functioning of P-LPS. Using C56BL6J mice and in vitro models, we show that kale imparts this protection by changing the gut microbiota composition, reducing the abundance of P-LPS-producing Enterobacteriaceae while increasing the representation of Bacteroidaceae, including species like Bacteroides thetaiotaomicron, which is known to produce immunosuppressive A-LPS. Kale thus modulates the P-LPS to A-LPS ratio. Relative levels of this ratio will exacerbate or inhibit inflammation. In addition, kale promotes the outgrowth of gram-positive taxa, specifically the species Turicibacter sanguinis. In follow-up studies in co-cultures of bacteria and intestinal epithelial cells (Caco-2 cells), we show that T. sanguinis protects gut barrier integrity by attenuating the adhesion and proliferation of E.coli O157:H7 (the source of P-LPS) and enhancing the expression of tight junction proteins. Further experiments in Caco-2 cells treated with P-LPS showed that the extract of kale promotes the expression and activity of intestinal alkaline phosphatase (IAP), an enzyme that deactivates P-LPS by dephosphorylating its lipid A moiety, thus rendering it unable to bind to TLR4 and initiate signaling. Lastly, using flow cytometry, we showed that in mouse primary peripheral blood mononuclear cells (PBMCs) and RAW 264.7 macrophages, kale extract inhibited the ability of P-LPS to bind to the TLR4-MD2 complex and CD14 receptors, thus attenuating the downstream inflammatory responses.
In summary, dietary supplementation with kale is protective against inflammation. Particularly inflammation induced by the bacterial metabolite P-LPS. It is protective against (i) P-LPS formation (by modulating the gut microbiota), (ii) P-LPS translocation (by strengthening the gut barrier), and (iii) the functioning of P-LPS (promoting its dephosphorylation and hence detoxification and preventing its binding to TLR4
Association between smoking cessation and risk for type 2 diabetes, stratified by post-cessation weight change: A systematic review and meta-analysis
No full textOBJECTIVE: While smoking cessation reduces health risks, its impact on type 2 diabetes mellitus (T2DM) remains complex when considering post-cessation weight gain. This systematic review and meta-analysis examined the association between smoking cessation and diabetes risk stratified by weight change and cessation duration. METHODS: We searched seven databases through April 14, 2025. Observational studies examining smoking cessation, weight changes, and T2DM were included. Random-effects models pooled hazard ratios (HRs) comparing recent and long-term quitters to continuous/never smokers, stratified by weight gain. RESULTS: Among eleven cohort studies, quitters with weight gain showed increased diabetes risk versus continuous smokers (HR = 1.71, 95 % CI: 1.12, 2.62), with recent quitters having greater risk (HR = 2.20, 95 % CI: 1.27, 3.82) but long-term quitters showing reduced risk (HR = 0.91, 95 % CI: 0.87, 0.95). Quitters without weight gain demonstrated no increased risk (recent: HR = 0.99, 95 % CI: 0.81, 1.02) and lower risk (long-term: HR = 0.84, 95 % CI: 0.81, 0.87). Compared to never-smokers, recent quitters had a higher T2DM risk regardless of weight status (with gain: HR = 1.61, 95 % CI: 1.03, 2.50; without gain: HR = 1.25, 95 % CI: 1.05, 1.48), while long-term quitters showed no significant difference. CONCLUSIONS: Smoking cessation temporarily increases T2DM risk, particularly with weight gain, but becomes protective long-term, emphasizing weight management.https://doi.org/10.1016/j.ypmed.2025.10842
CrabFormer: RGB-D Segmentation and Pose Estimation for Front-End Loading of Piled Chesapeake Blue Crabs
No full textCrabFormer is a multitasking transformer model developed to tackle the challenges of front-end loading in the automated processing of Chesapeake blue crabs. Existing methods often struggle to accurately identify crabs in chaotic, piled configurations, where occlusions and overlapping are common. CrabFormer addresses this by combining instance segmentation and keypoint prediction using RGB-D inputs to detect crabs and estimate their orientation. Utilizing a dual-patch Swin-T backbone, the model processes RGB and depth data separately, effectively capturing visual and geometric features. CrabFormer is evaluated on a custom dataset comprising discrete, overlapping, and piled crabs. It achieves a segmentation Average Precision (AP) of 67.84 and Average Recall (AR) of 76.29, while its keypoint prediction AP and AR are 62.43 and 77.23, respectively. The model outperforms state-of-the-art transformer-based segmentation and keypoint prediction models, particularly in the most complex piled cases, demonstrating improvements in both AP and AR. It excels in identifying the topmost crab in a pile, a key task for automated processing. Additionally, CrabFormer achieves competitive inference times while maintaining superior multitasking performance. These results highlight CrabFormer’s potential to enhance the automation of front-end loading in the seafood industry, reducing labor reliance and improving operational efficiency. Future work will expand the dataset and explore the model’s applicability to other crustaceans with similar morphological complexities
Democratizing Academic Librarianship: Ten Years of Community-Building Through a Graduate Fellowship
No full textDeveloped in partnership between a University Library and a College of Information, the presenters have created and led a three-semester teacher training fellowship that prepares MLIS students for careers in academic librarianship. In celebration of the Fellowship program*s 10th anniversary, we offer reflections from a decade of research and practice, including findings from an ongoing qualitative study featuring interviews with Fellowship alumni. While this presentation focuses on our institution’s Fellowship program, the implications of our findings are relevant to anyone interested in supporting early-to-mid-career librarians as they navigate the challenges, opportunities, and future of the profession. Objective 1: Participants will be able to identify and apply effective strategies for developing and maintaining professional development programs based on a decade of insights from a student-centered fellowship program. Objective 2: Participants will learn to evaluate which components of a professional development program are most impactful for participants, drawing on qualitative findings from interviews with fellowship alumni. Objective 3: Participants will gain actionable recommendations for supporting early-to-mid career librarians in navigating career transitions, building scholarly portfolios, and fostering community-building, informed by findings from interviews with fellowship alumni
Engaging Small Group Open Access Education for STEM Students and Faculty
No full textOpen access (OA) is one of the signature dishes of open science. Yet, engaging STEM departments in OA and the library’s supporting resources can present a challenge. Motivating faculty and graduate students to attend a lecture or workshop facilitated by the libraries can be difficult as participants often have neither the time nor interest in attending a generalized event. Furthermore, these stakeholders often feel the specific concerns of their discipline or department will not be addressed. Therefore, there are many advantages to conducting OA education in extant cohort-specific environments such as department meetings, graduate affinity groups, small discussion settings, or classrooms. For participants, education conducted in these environments accommodates their busy schedules and creates space for peer-to-peer and discipline-specific conversations, questions, and concerns. For librarians, these can be unique opportunities to engage with faculty and students on issues of open access and to present library resources to audiences that are otherwise difficult to access. Our recipe, for effective OA education in support of open science, is a winner for libraries and the patrons they serve.
Based on sessions conducted at the University of Maryland, College Park to several engineering departments, our recipe covers how to develop and deliver effective open access education targeted towards individual communities. In it, liaison librarians and specialists in open scholarship, scholarly communications, or publishing collaborate to whip up effective outreach to different STEM departments. Librarians can then customize the recipe to develop open access education targeted towards individual communities’ tastes. Building on a set of clear and accessible OA teaching materials, we explore the role of a liaison librarian in opening discussions with cohorts of faculty and students around campus. We combine this with suggestions of how to utilize knowledge of constituent communities’ goals, concerns, (and possibly, misconceptions) around open access and open science to most effectively engage with them. Those from libraries without access to all of the ingredients need not worry, this recipe can be adapted to smaller academic settings that may not have an open scholarship or publishing librarian. It can also be tailored for larger institutions with publishing departments and multiple specialized staff. For those with different dietary requirements, the format of the outreach is customizable from department presentation, to lunch seminar, to classroom instruction, to informal discussion.
This recipe will provide:
A set of teaching materials, published under a CC0 license, including information on the different OA publishing models (ie green, gold, diamond), benefits and concerns around OA publishing, common misconceptions, and how OA and, more generally, open science practices are becoming increasingly encouraged if not required
Supplemental materials to help librarians engage in preparatory conversations with audiences or their representatives in order to adapt the materials
A checklist and guidance to research departmental and cohort activities related to OA and open science such as the use of library resources, publishing behaviors, etc.
We hope our recipe can be used and adapted to accommodate OA education for varied STEM audiences, making it a timely, practical, useful plate that belongs in pretty much any library’s recipe box
INVESTIGATION OF THE NOVEL ANTITERMINATION MECHANISM OF LOAP, A NUSG SPECIALIZED PARALOG
No full textThe transcription factor NusG plays an important role in the transcription elongation complex across all domains of life. During elongation, the NusG-NTD forms contacts to RNAP while the NusG-CTD dynamically interacts with other proteins, affecting processivity, transcription termination, and in some bacteria, transcription-translation coupling. NusG is integral to antitermination complexes, where it associates with additional factors to modify the TEC in order to bypass termination events at distinct gene clusters. In Gammaproteobacteria, these complexes enhance the expression of ribosomal RNA operons, bacteriophage operons, and CRISPR arrays. Specialized NusG paralogs, such as LoaP, RfaH, or UpxY, are widespread in bacteria and likely form their own unique antitermination complexes. RfaH, the only well-studied paralog, binds to a paused TEC via a specific non-template DNA sequence, then prevents Rho termination while enhancing transcription-translation coupling of targeted operons. It is unclear whether other NusG paralogs use similar mechanisms. LoaP is primarily encoded by Bacillota, Actinomycetota and Spirochaetota, and while
regulons influenced by LoaP have only been identified in a few organisms, the recurring location of loaP adjacent to long operons responsible for the biosynthesis of secondary metabolites suggests a regulatory relationship. Previously, Bacillus velezensis LoaP was shown to enhance transcription of the difficidin and macrolactin antibiotic synthesis operons, but its antitermination determinants were unknown. Presented herein is the reconstitution of difficidin operon (dfn) antitermination activity in vitro following the purification of RNA polymerase and additional transcription factors encoded by Bacilli. The dfn 5’ leader region contains a small RNA hairpin ligand essential for LoaP antitermination activity both in vivo and in vitro, and an intrinsic terminator that is highly dependent on NusA. The addition of LoaP specifically antagonizes NusA, thereby promoting readthrough of the termination region without the need for additional factors. These findings demonstrate the basic requirements of the LoaP class of NusG paralogs and indicate that the LoaP antitermination mechanism differs significantly from that of the RfaH – and more broadly, the Gram-positive – paradigm
A COLLABORATIVE PIANIST'S SURVEY OF MEZZO-SOPRANO TROUSER ROLES IN OPERA
No full textThis dissertation consists of a recording accompanied by extensive program notes centered on ten iconic mezzo-soprano trouser role arias in opera, spanning from the Baroque to the early 20th century. The focus is on exploring the vocal, musical, and dramatic aspects of each aria, emphasizing both the technical demands and interpretive nuances required of singers and collaborative pianists alike. Each chapter delves into a specific aria, offering insights into the stylistic conventions of its time, the role's dramatic context, and its vocal characteristics. Through detailed analysis, the collaborative pianist’s role is examined, offering practical guidance for preparing the orchestra reductions. Additionally, a spotlight is concentrated on the mezzo-soprano's versatile voice and the unique challenges presented in portraying male characters in opera, including how each composer utilizes the mezzo-soprano to enhance narrative and emotional depth.
The ten mezzo-soprano arias and duets which comprise this dissertation range from Handel and Mozart to Meyerbeer, Gounod, Humperdinck, Massenet, and concluding with Strauss. The recordings were made in Santa Fe, NM, during July and August 2024, and in Salt Lake City, UT, in January 2025. Featured performers include mezzo-sopranos Ashlyn Brown, Kaylee Nichols, Shannon Keegan, and Sarah Coit, as well as sopranos Elisa Sunshine and Maureen McKay. The dissertation recording can be found in the Digital Repository at the University of Maryland (DRUM
Empirically Evaluating the Security and Privacy Implications of Persistent Network Identifiers
No full textPersistent, globally-unique link- and network-layer addresses present a privacy threat to the owners of the devices to which they are assigned, particularly when the device is physically or logically mobile. Best practices recommend the use of addresses that are ephemeral, random, or both, to protect user privacy. To date, there have been no large-scale, empirical studies of the degree to which these recommendations are being implemented in practice without privileged access to network data from a commercial third party. This is due, in part, to the difficulty of obtaining the quantities of addresses needed to draw any conclusions. Obtaining client IPv6 addresses is challenging without running a network service or partnering with an ISP; obtaining in-use link-layer addresses is difficult without being in physical or logical proximity to the interfaces to which they are assigned.
In this thesis, I demonstrate that a low-power attacker can collect network addresses at scale and that recommendations to prevent persistent identifiers are not being followed in practice, resulting in a substantial degradation of user privacy. To demonstrate this, I obtain large-scale corpora of link- and network-layer addresses from a variety of novel sources. Using this data, I then show the feasibility of a variety of attacks. For e.g., I show that an adversary can passively gather billions of active, client IPv6 addresses that can be used to track individual devices longitudinally and across network changes. I demonstrate IPv6-specific home network vulnerabilities, such as a lack of stateful firewalling, that permit attackers to discover in-home IoT devices. Using archival Wikimedia data, I demonstrate a novel methodology for collecting millions of historical, client IPv6 addresses. Switching to a different address space, I then show that a low-power attacker can obtain the geolocations of billions of Wi-Fi access point geolocations remotely, and track their movements over time. I demonstrate that, when combined with Wi-Fi access point geolocation data, some IPv6 devices can be precisely geolocated due to leaked link-layer identifiers in IPv6 addresses. Finally, I distill the key components of privacy-preserving network addressing systems, and offer recommendations for how to adapt today's addressing schemes to these principles
ESSAYS ON FIRMS AND LABOR MARKETS
No full textIn this dissertation I examine how macroeconomic conditions and government policies shape individual and collective economic behaviors in entrepreneurship and the U.S. labor market. I examine how financial constraints affect business formation along with the role government policies play in supporting entrepreneurial ventures. Then I analyze the changes in labor supply directly following the Covid-19 pandemic.
My first chapter, "The Effect of Rising Higher Education Costs on Business Formation,'' examines the effect of increases in tuition on entrepreneurship. Between 2000 and 2014, yearly real average college tuition increased by 31% while the average student loan balance increased by 21%. I use administrative data to examine how an increase in the cost of higher education affects the likelihood of forming a business after graduation. I instrument for realized tuition by exploiting the variation in total four-year tuition due to differences in the length of exposure to increased tuition between students in different enrollment years at universities that experienced a large “sticker price” tuition shock. I find that for every $10,000 increase in tuition there is a 3.0 percentage point (41 percent) decrease in the likelihood of being an owner or early joiner of a business. This decline is 7.8 percentage points larger for individuals at universities that have larger student loan balances and 4.1 percentage points higher for individuals with parents who did not complete college. The negative effect on business formation does not exist for students attending universities with more generous financial aid. These results suggest that increasing higher education costs are deterring recent graduates from engaging in entrepreneurial activity.
In my second chapter, "After the Storm: How Emergency Liquidity Helps Small Businesses Following Natural Disasters'', co-authored with Benjamin Collier and Sabrina Howell, we study whether emergency credit prevents long-term financial distress from severe climate events. We study the causal effects of government-provided recovery loans to businesses following natural disasters. These modestly subsidized loans could enable firms to survive and grow. Alternatively, they might prop up firms that should exit, or crowd out private lenders. We show that the loans reduce exit and bankruptcy, increase employment and revenue, unlock private credit, and reduce delinquency. These effects, especially the crowding-in of private credit, appear to reflect resolving uncertainty about repair. We do not find credit reallocation away from neighboring firms and see some evidence of positive spillovers on local entry.
In my final chapter, "Where are the missing workers? Anticipated and unanticipated labor supply changes in the pandemic’s aftermath,'' co-authored with Katharine G. Abraham, we quantify the changes in labor supply in the two years following the Covid-19 pandemic. Labor force participation and average hours of work both fell sharply at the beginning of the COVID-19 pandemic. Neither had fully recovered by the end of 2022. The drop in participation between December 2019 and December 2022 implies a loss of 3 million people from the labor force; the decline in average hours over the same period translates to the equivalent of 2.6 million fewer workers. Demographic and other trend factors that pre-dated the pandemic explain most of the participation shortfall. Taken together, COVID-19-related health effects and the persistent (though shrinking) effects of the fear of contracting COVID-19 more than explain the rest. In contrast, pre-pandemic factors account for little of the shortfall in hours. COVID-19-related health effects account for perhaps 40 percent of that decline, but we are unable to explain the majority of the hours shortfall. We speculate that the lower level of hours in the post-pandemic period may reflect a shift in the desired balance between work and other aspects of workers’ lives