cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Tangent spaces and tangent bundles for diffeological spaces
Creators: name: Christensen, J. Daniel
name: Wu, Enxin
Publisher: name: arXiv
Year: 2014
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 57P99 (Primary) 58A05 (Secondary)

description: We study how the notion of tangent space can be extended from smooth manifolds to diffeological spaces, which are generalizations of smooth manifolds that include singular spaces and infinite-dimensional spaces. We focus on two definitions. The internal tangent space of a diffeological space is defined using smooth curves into the space, and the external tangent space is defined using smooth derivations on germs of smooth functions. We prove fundamental results about these tangent spaces, compute them in many examples, and observe that while they agree for smooth manifolds and many of the examples, they do not agree in general. After this, we recall Hector's definition of the tangent bundle of a diffeological space, and show that both scalar multiplication and addition can fail to be smooth, revealing errors in several references. We then give an improved definition of the tangent bundle, using what we call the dvs diffeology, which ensures that scalar multiplication and addition are smooth. We establish basic facts about these tangent bundles, compute them in many examples, and study the question of whether the fibres of tangent bundles are fine diffeological vector spaces. Our examples include singular spaces, spaces whose natural topology is non-Hausdorff (e.g., irrational tori), infinite-dimensional vector spaces and diffeological groups, and spaces of smooth maps between smooth manifolds (including diffeomorphism groups).
description: v2 and v3: minor corrections and improvements to exposition; 27 pages; to appear in Cahiers de Topologie et G\'eom\'etrie Diff\'erentielle
Spindle assembly checkpoint proteins are positioned close to core microtubule attachment sites at kinetochores
Creators: name: Varma, Dileep
name: Wan, Xiaohu
name: Suzuki, Aussie
name: Cheerambathur, Dhanya
name: Salmon, E.D.
name: Lawrimore, Josh
name: Gassmann, Reto
name: Desai, Arshad
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Depletion analyses and nanometer-scale mapping of spindle assembly checkpoint proteins reveal how these proteins are integrated within the substructure of the kinetochore.Spindle assembly checkpoint proteins have been thought to reside in the peripheral corona region of the kinetochore, distal to microtubule attachment sites at the outer plate. However, recent biochemical evidence indicates that checkpoint proteins are closely linked to the core kinetochore microtubule attachment site comprised of the Knl1–Mis12–Ndc80 (KMN) complexes/KMN network. In this paper, we show that the Knl1–Zwint1 complex is required to recruit the Rod–Zwilch–Zw10 (RZZ) and Mad1–Mad2 complexes to the outer kinetochore. Consistent with this, nanometer-scale mapping indicates that RZZ, Mad1–Mad2, and the C terminus of the dynein recruitment factor Spindly are closely juxtaposed with the KMN network in metaphase cells when their dissociation is blocked and the checkpoint is active. In contrast, the N terminus of Spindly is ∼75 nm outside the calponin homology domain of the Ndc80 complex. These results reveal how checkpoint proteins are integrated within the substructure of the kinetochore and will aid in understanding the coordination of microtubule attachment and checkpoint signaling during chromosome segregation.
Conflict and Supply Risks in Critical Materials for the Energy Transition
Creators: name: Freeman, Sophia
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023

description: This research investigates the relationships between conflicts and the resources necessary to promote a clean energy transition, including lithium, cobalt, graphite, nickel, and rare earth elements. It documents the current production and extraction of these resources, including the countries of origin and major global actors involved in the process. The next step will be to identify conflicts that have arisen around the extraction and production of these resources, including conflicts related to property rights, labor issues, ethnic and civil war, and international civil and military conflicts. Finally, the project explores the approaches of the US government and the European Union to balancing conflict resolution with the need for critical resources for the clean energy transition. Ultimately, this research provides insight into the role of resource control in fueling conflict and the potential for peaceful resolution of such conflicts in the context of clean energy transitions. This presentation summarizes such findings.
IPBES invasive alien species assessment, data management report for Chapter 3. Section 3.3.4.6: Sea level rise
Creators: name: Blanchard, Ryan
Publisher: name: Zenodo
Year: 2023
Subjects: Data management report

description: Section 3.3.4.6 assesses the role of sea level rise as a driver of biological invasions for chapter 3 of IPBES thematic assessment of invasive alien species and their control. The experts conducted a systematic review to report on the existing knowledge on this driver. This systematic review consists in the main source of evidence for the section.
Implementation of a 3-D Border-Sequential Thinning Algorithm for Automatic Characterization of Tumor Malignancy in Super-Resolution Ultrasonic Images
Creators: name: Choi, Albert
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023

description: An efficient and robust software is paramount to accurately and quickly acquiring tortuosity metrics from ultrasound localization microscopy of microbubbles that can determine if cancer should be suspected. Currently, a software that uses the manual segmentation method is very slow and is a limiting factor for using this technology in research and clinical settings. While another software – the automatic segmentation algorithm – is fast, its consistency of the tortuosity metrics to the manual segmentation method is questioned. Therefore, the goal of this project is two-fold: 1) determine if the vessel tortuosity metrics calculated by the manual-selection method are comparable to those of the automatic vessel segmentation algorithm and 2) determine how the automatic segmentation algorithm could be improved to yield more accurate tortuosity metrics for its standalone use in research and clinical settings.
Effects of exercise and folic acid supplementation on vascular health in middle-aged men and postmenopausal women
Creators: name: Craig, Jen
Publisher: name: Loughborough University
Year: 2021
Subjects: Other health sciences not elsewhere classified

description: Advancing age increases the risk of cardiovascular disease (CVD), largely due to the development of systemic vascular endothelial dysfunction and stiffening of the large elastic arteries. This thesis included three studies, which investigated the independent and combined effects of exercise and short-term folic acid (FA) supplementation on cardiovascular responses in healthy middle-aged men (MM) and postmenopausal women (PMW). Young men (YM) and premenopausal women (PreM) were studied under the same experimental conditions to ascertain responses in the healthy arterial system. The methodology included pulse wave analysis, venous occlusion plethysmography and flow mediated dilation (FMD) to assess indexes of aortic wave reflection (AWRi), calf blood flow (CBF) and brachial artery endothelium-dependent vasodilation, respectively. [...]
The tension mounts: Stress fibers as force-generating mechanotransducers
Creators: name: Wittchen, Erika S.
name: Burridge, Keith
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Stress fibers (SFs) are often the most prominent cytoskeletal structures in cells growing in tissue culture. Composed of actin filaments, myosin II, and many other proteins, SFs are force-generating and tension-bearing structures that respond to the surrounding physical environment. New work is shedding light on the mechanosensitive properties of SFs, including that these structures can respond to mechanical tension by rapid reinforcement and that there are mechanisms to repair strain-induced damage. Although SFs are superficially similar in organization to the sarcomeres of striated muscle, there are intriguing differences in their organization and behavior, indicating that much still needs to be learned about these structures.
title: Transcriptional regulation of yir genes in Plasmodium yoelii yoelii infected erythrocytes
Creators: name: Fonager, Jannik
Publisher: name: The Open University
Year: 2006

description: In 1998, a large multi gene family was discovered in Plasmodium vivax (del Portillo et al., 1998). This multigene family was termed vir, and later studies showed that vir homologues existed in the three rodent malaria species, Plasmodium chabaudi (cir), Plasmodium berghei (bir) and Plasmodium yoelii (yir). By 5x coverage sequencing of Plasmodium yoelii 17X, 838 yir genes were predicted (Carlton et al., 2002), making this the largest known multi gene family in Plasmodium. YIR proteins are expressed at the surface of infected erythrocytes (Cunningham et al., 2005), and therefore this family is thought to be involved in antigenic variation.

The aim of this thesis was to examine how P.yoelii regulates transcription of the yir family. The yir gene structure was verified experimentally, and phylogenetic analysis showed that yir genes could be divided into five supergroups consisting of yir genes with different sizes and subtelomeric localisation. In the blood stages, numerous yir genes were transcribed from all the supergroups in immunocompromised mice. However, a maximum of two yir genes were transcribed in single infected erythrocytes at the Schizont stage, which suggested strong silencing mechanisms. The transcriptional start and polyadenylation sites were identified experimentally, and it was found that both occurred at highly conserved motifs. In addition, the transcription initiation site was located close to an unusual and universally conserved triple-repeat motif, and it was found that all yir transcripts in two populations of parasites initiated downstream of this motif. Transfection experiments were performed in order to examine the role of this motif, but no solid conclusions could be drawn from these. Several alternative splicing events were detected in the yir 5'UTRs, and one of these led to exon 1 skipping of a yir gene. Through bioinformatic analysis of yir 5' intergenic regions, it was found that the UTR introns had a discrete distribution amongst the yir supergroups.
Humoral Immune Response and Safety of SARS-CoV-2 Vaccination in Pediatric Inflammatory Bowel Disease
Creators: name: Chen W.
name: Bellaguarda E.A.
name: Cross R.K.
name: Zhang X.
name: Fernando M.
name: Adler J.
name: Ungaro R.C.
name: Firestine A.
name: Strople J.A.
name: Bastidas M.
name: Hernandez C.G.
name: Bousvaros A.
name: Dai X.
name: Kastl A.J.
name: Boccieri M.E.
name: Zikry M.
name: Weaver K.N.
name: Dubinsky M.C.
name: Higgins P.D.R.
name: Kappelman M.D.
name: Chun K.Y.
name: Farraye F.A.
name: Bewtra M.
name: Long M.D.
name: Watkins R.
name: Craig R.G.
Publisher: name: Wolters Kluwer Health
Year: 2023

description: INTRODUCTION:Children with inflammatory bowel disease (IBD) may respond differently to COVID-19 immunization as compared with healthy children or adults with IBD. Those younger than 12 years receive a lower vaccine dose than adults. We sought to describe the safety and humoral immune response to COVID-19 vaccine in children with IBD.METHODS:We recruited children with IBD, ages 5-17 years, who received ≥ 2 doses of the BNT162b2 vaccine by a direct-to-patient outreach and at select sites. Patient demographics, IBD characteristics, medication use, and vaccine adverse events were collected. A subset of participants had quantitative measurement of anti-receptor binding domain IgG antibodies after 2-part immunization.RESULTS:Our study population included 280 participants. Only 1 participant required an ED visit or hospitalization because of an adverse event. Of 99 participants who underwent anti-receptor binding domain IgG antibody measurement, 98 had a detectable antibody, with a mean antibody level of 43.0 g/mL (SD 67) and a median of 22 g/mL (interquartile range 12-38). In adjusted analyses, older age (P = 0.028) and antitumor necrosis factor monotherapy compared with immunomodulators alone (P = 0.005) were associated with a decreased antibody level. Antibody response in patients treated with antitumor necrosis factor combination vs monotherapy was numerically lower but not significant.DISCUSSION:Humoral immune response to COVID-19 immunization in children with IBD was robust, despite a high proportion of this pediatric cohort being treated with immunosuppressive agents. Severe vaccine-related AEs were rare. Overall, these findings provide a high level of reassurance that pediatric patients with IBD respond well and safely to SARS-CoV-2 vaccination.
HPV Prevalence and Cervical Intraepithelial Neoplasia among HIV-infected Women in Yunnan Province, China: A Pilot Study
Creators: name: Li, Zu-An
name: Sahasrabuddhe, Vikrant V.
name: Smith, Jennifer S.
name: Mei, Run-Bo
name: Wang, Xian-Guo
name: Tiggelaar, Sarah M.
name: Zhang, Hong-Yun
name: Jiang, Cheng-Qin
name: Qiao, You-Lin
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2012

description: To determine the prevalence of HPV and cervical neoplasia among HIV-infected women in southwestern China.
Computing observables in curved multifield models of inflation - A guide (with code) to the transport method
Creators: name: Dias, Mafalda
name: Frazer, Jonathan
name: Seery, David
Publisher: name: arXiv
Year: 2015
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We describe how to apply the transport method to compute inflationary observables in a broad range of multiple-field models. The method is efficient and encompasses scenarios with curved field-space metrics, violations of slow-roll conditions and turns of the trajectory in field space. It can be used for an arbitrary mass spectrum, including massive modes and models with quasi-single-field dynamics. In this note we focus on practical issues. It is accompanied by a Mathematica code which can be used to explore suitable models, or as a basis for further development.
description: 22 pages; accompanying code available from transportmethod.com. v3: improved treatment of tensor power spectrum and tensor spectral index
Child and Adolescent Obesity and Employment Sector in Urban China
Creators: name: Zimmer, Zachary
name: Li, Yi
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Despite its importance as a part of the economic reform in China, sectoral employment has been overlooked as a potential determinant of child and adolescent obesity (CAO). Using large-scale longitudinal data from surveys conducted from 1989 to 2006, this paper examines the relationship between the sector in which a parent is employed and CAO, with the sector being based on ownership and categorised as either state or non-state. Analyses of over 1,700 children and adolescents show that children and adolescents whose parents work in the state sector are less likely to be obese. Patterns of sectoral employment's effect are robust across time periods, in fixed-effects models, and across multiple measures of obesity. Additionally, the paper shows that socioeconomic characteristics of the parent, such as income, education, and occupation, typically thought to be important predictors of CAO, are not as important when the parental working sector is included in the models.
A Homogeneous Method to Measure Nucleotide Exchange by α-Subunits of Heterotrimeric G-Proteins Using Fluorescence Polarization
Creators: name: Kimple, Adam J.
name: Klein, Klara R.
name: Siderovski, David P.
name: Muller, Robin E.
name: Hutsell, Stephanie Q.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: The mainstay of assessing guanosine diphosphate release by the α-subunit of a heterotrimeric G-protein is the [35S]guanosine 5′-O-(3-thiotriphosphate) (GTPγS) radionucleotide-binding assay. This assay requires separation of protein-bound GTPγS from free GTPγS at multiple time points followed by quantification via liquid scintillation. The arduous nature of this assay makes it difficult to quickly characterize multiple mutants, determine the effects of individual variables (e.g., temperature and Mg2+ concentration) on nucleotide exchange, or screen for small molecule modulators of Gα nucleotide binding/cycling properties. Here, we describe a robust, homogeneous, fluorescence polarization assay using a red-shifted fluorescent GTPγS probe that can rapidly determine the rate of GTPγS binding by Gα subunits.
IPBES Invasive Alien Species Assessment, data management report for Chapter 3. Section 3.3.4.5: Fire regime changes
Creators: name: Xavier, Rafael O.
Publisher: name: Zenodo
Year: 2023
Subjects: Data management report

description: Section 3.3.4.5 assesses the role of fire as a driver of biological invasions in Chapter 3 of IPBES assessment of invasive alien species and their control. The experts conducted a systematic review to report on the existing knowledge on this driver. This systematic review consists in the main source of evidence for the section.
Nonequilibrium transport in density-modulated phases of the second Landau level
Creators: name: Baer, S.
name: Rössler, C.
name: Hennel, S.
name: Overweg, H. C.
name: Ihn, T.
name: Ensslin, K.
name: Reichl, C.
name: Wegscheider, W.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate non-equilibrium transport in the reentrant integer quantum Hall phases of the second Landau level. At high currents, we observe a transition from the reentrant integer quantum Hall phases to classical Hall-conduction. Surprisingly, this transition is markedly different for the hole- and electron sides of each spin-branch. While the hole bubble phases exhibit a sharp transition to an isotropic compressible phase, the transition for the electron side occurs via an intermediate phase. This might indicate a more complex structure of the bubble phases than currently anticipated, or a breaking of the particle-hole symmetry. Such a symmetry breaking in the second Landau level might also have consequences for the physics at filling factor $ν$=5/2.
description: 11 pages Supplemental Material available at http://link.aps.org/supplemental/10.1103/PhysRevB.91.195414
Mental Illness(es) in Picture Books: A Content Analysis
Creators: name: Perez, Natalie Marie
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023
Subjects: Content analysis (Communication)
Mental illness
Picture books

description: This research study investigates 1) how mental illness(es) are represented and depicted within youths’ picture books and 2) the overall implications of said representations and depictions. Which mental illnesses are most/least depicted? Are the depictions accurate? Who is the character with the condition? How is the character represented? Are the mental illnesses personified? If yes, how so? Which symptoms are acknowledged? Are treatments acknowledged? How are the characters' experiences concluded? Using both quantitative and qualitative analysis, a sample of 20 picture books were read and coded against criteria involving the research questions. This study provides insight into how, and to what extent, individuals with mental illness(es) are represented within youths’ literature; accurate depictions can spread awareness regarding and further normalize mental illness(es) for youth readers.
Archival Meta-Metadata: Revision History and Positionality of Finding Aids
Creators: name: King, Owen C.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023
Subjects: Archivists
Finding aids
Metadata

description: This paper starts from two observations about archival description.  First, creating finding aids requires significant judgment and interpretation, and is therefore inevitably influenced by the positionalities—the perspectives, personal histories, and social identities—of the archivists.  Second, finding aids sometimes call for revision, sometimes to fit a new data standard or reflect an evolving collection, but also to correct errors, reduce bias, and remove harmful language.  In light of these observations and related theoretical work, this paper offers a rationale for recording metadata about finding aids, including revision history and authorship.  Then it presents the results of a survey of state archivists in the US, who were asked about their descriptive practices and opinions regarding disclosing their authorship of finding aids.  Results reveal diverse practices, as well as hesitation to embrace expressions of positionality in the context of description.  Finally, the paper concludes with two general recommendations regarding metadata about finding aids.
Seismic isolation of Advanced LIGO: Review of strategy, instrumentation and performance
Creators: name: Matichard, F.
name: Lantz, B.
name: Mittleman, R.
name: Mason, K.
name: Kissel, J.
name: McIver, J.
name: Abbott, B.
name: Abbott, R.
name: Abbott, S.
name: Allwine, E.
name: Barnum, S.
name: Birch, J.
name: Biscans, S.
name: Celerier, C.
name: Clark, D.
name: Coyne, D.
name: DeBra, D.
name: DeRosa, R.
name: Evans, M.
name: Foley, S.
name: Fritschel, P.
name: Giaime, J. A.
name: Gray, C.
name: Grabeel, G.
name: Hanson, J.
name: Hardham, C.
name: Hillard, M.
name: Hua, W.
name: Kucharczyk, C.
name: Landry, M.
name: Roux, A. Le
name: Lhuillier, V.
name: Macleod, D.
name: Macinnis, M.
name: Mitchell, R.
name: Reilly, B. O
name: Ottaway, D.
name: Paris, H.
name: Pele, A.
name: Puma, M.
name: Radkins, H.
name: Ramet, C.
name: Robinson, M.
name: Ruet, L.
name: Sarin, P.
name: Shoemaker, D.
name: Stein, A.
name: Thomas, J.
name: Vargas, M.
name: Venkateswara, K.
name: Warner, J.
name: Wen, S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Isolating ground-based interferometric gravitational wave observatories from environmental disturbances is one of the great challenges of the advanced detector era. In order to directly observe gravitational waves, the detector components and test masses must be highly inertially decoupled from the ground motion not only to sense the faint strain of space-time induced by gravitational waves, but also to maintain the resonance of the very sensitive 4 km interferometers. This article presents the seismic isolation instrumentation and strategy developed for Advanced LIGO interferometers. It reviews over a decade of research on active isolation in the context of gravitational wave detection, and presents the performance recently achieved with the Advanced LIGO observatory. Lastly, it discusses prospects for future developments in active seismic isolation and the anticipated benefits to astrophysical gravitational wave searches. Beyond gravitational wave research, the goal of this article is to provide detailed isolation strategy guidelines for sensitive ground-based physics experiments that may benefit from similar levels of inertial isolation.
description: Pre-print version submitted to CQG, F Matichard et al 2015 Class. Quantum Grav. 32 185003
Identification of Human Ether-à-go-go Related Gene Modulators by Three Screening Platforms in an Academic Drug-Discovery Setting
Creators: name: Hufeisen, Sandy
name: Huang, Xi-Ping
name: Mangano, Thomas
name: Roth, Bryan L.
name: Setola, Vincent
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: The human Ether-à-go-go related gene (hERG) potassium channel is responsible for the rapid delayed rectifier potassium current that plays a critical role in the repolarization of cardiomyocytes during the cardiac action potential. In humans, inhibition of hERG by drugs can prolong the electrocardiographic QT interval, which, in rare instance, leads to ventricular arrhythmia and sudden cardiac death. As such, several medications that block hERG channels in vitro have been withdrawn from the market due to QT prolongation and arrhythmias. The current FDA guidelines recommend that drug candidates destined for human use be evaluated for potential hERG activity (www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/ucm074963.pdf). Here, we employed automated planar patch clamp (APPC), high-throughput fluorescent Tl+flux, and moderate-throughput [3H]dofetilide competition binding assays to characterize a panel of 49 drugs for their activities at the hERG channel. Notably, we used the same HEK293-hERG cell line for all assays, facilitating comparisons of hERG potencies across screening platforms. In general, hERG inhibitors were most potent in APPC assays, intermediate potent in [3H]dofetilide binding assays, and least potent in Tl+flux assays. Binding affinity constants (pKivalues) and Tl+flux potencies (pEC50values) correlated well with APPC pEC50values. Further, the inhibitory potencies of many known hERG inhibitors in APPC matched literature values from manual and/or automated patch clamp systems. We also developed a novel fluorescent Tl+flux assays to measure the effects of drugs that modulate hERG trafficking and surface expression.
Bayesian Particle Tracking of Traffic Flows
Creators: name: Polson, Nicholas
name: Sokolov, Vadim
Publisher: name: arXiv
Year: 2014
Subjects: subject: Applications (stat.AP)
subject: FOS: Computer and information sciences
subject: 60K35

description: We develop a Bayesian particle filter for tracking traffic flows that is capable of capturing non-linearities and discontinuities present in flow dynamics. Our model includes a hidden state variable that captures sudden regime shifts between traffic free flow, breakdown and recovery. We develop an efficient particle learning algorithm for real time on-line inference of states and parameters. This requires a two step approach, first, resampling the current particles, with a mixture predictive distribution and second, propagation of states using the conditional posterior distribution. Particle learning of parameters follows from updating recursions for conditional sufficient statistics. To illustrate our methodology, we analyze measurements of daily traffic flow from the Illinois interstate I-55 highway system. We demonstrate how our filter can be used to inference the change of traffic flow regime on a highway road segment based on a measurement from freeway single-loop detectors. Finally, we conclude with directions for future research.
High-Throughput Screening for RecA Inhibitors Using a Transcreener Adenosine 5′- O -Diphosphate Assay
Creators: name: Janzen, William P.
name: Kireev, Dmitri
name: Peterson, Eliza J.R.
name: Singleton, Scott F.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2012

description: The activities of the bacterial RecA protein are involved in the de novo development and transmission of antibiotic resistance genes, thus allowing bacteria to overcome the metabolic stress induced by antibacterial agents. RecA is ubiquitous and highly conserved among bacteria, but has only distant homologs in human cells. Together, this evidence points to RecA as a novel and attractive antibacterial drug target. All known RecA functions require the formation of a complex formed by multiple adenosine 5′-O-triphosphate (ATP)-bound RecA monomers on single-stranded DNA. In this complex, RecA hydrolyzes ATP. Although several methods for assessing RecA's ATPase activity have been reported, these assay conditions included relatively high concentrations of enzyme and ATP and thereby restricted the RecA conformational state. Herein, we describe the validation of commercial reagents (Transcreener® adenosine 5′-O-diphosphate [ADP]2 fluorescence polarization assay) for the high-throughput measurement of RecA's ATPase activity with lower concentrations of ATP and RecA. Under optimized conditions, ADP detection by the Transcreener reagent provided robust and reproducible activity data (Z′=0.92). Using the Transcreener assay, we screened 113,477 small molecules against purified RecA protein. In total, 177 small molecules were identified as confirmed hits, of which 79 were characterized by IC50 values ≤10 μM and 35 were active in bioassays with live bacteria. This set of compounds comprises previously unidentified scaffolds for RecA inhibition and represents tractable hit structures for efforts aimed at tuning RecA inhibitory activity in both biochemical and bacteriological assays.
Investigating Subcommunities in BookTok: An Analysis Using Hashtags and Videos
Creators: name: Flores, Zoe
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023
Subjects: Social media
Hashtags (Metadata)
Internet videos

description: 
TikTok is a social media application that is popular around the world. According to TikTok, one of its most popular communities is BookTok, an informal community that celebrates all things reading. BookTok has powerful influence on publishing, libraries, bookstores, and reading habits of young adults and teens. It is therefore essential to understand the underlying information and social phenomena behind the hashtag “BookTok.” Existing research and TikTok itself refer to BookTok as a singular community, but with billions of views, is it one unified community or a collection of smaller subcommunities? This investigation used quantitative and qualitative content analysis to take a preliminary look at common hashtags, authors, books, and themes present in videos from potential subcommunities. The analysis found that although there may be subcommunities such as #yabooktok (Young Adult BookTok) within BookTok, these subcommunities are still part of and identify with the larger BookTok community.
Regular phase operator and SU(1,1) coherent states of the harmonic oscillator
Creators: name: Varro, Sandor
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A new solution is proposed to the long-standing problem of describing the quantum phase of a harmonic oscillator. In terms of an'exponential phase operator', defined by a new 'polar decomposition' of the quantized amplitude of the oscillator, a regular phase operator is constructed in the Hilbert-Fock space as a strongly convergent power series. It is shown that the eigenstates of the new 'exponential operators are SU(1,1) coherent states in the Holstein-Primakoff realization. In terms of these eigenstates, the diagonal representation of phase densities and a generalized spectal resolution of the regular phase operator are derived, which suit very well to our intuitive pictures on classical phase-related quantities
description: 34 pages, 3 Figures
High-Content Assays for Hepatotoxicity Using Induced Pluripotent Stem Cell–Derived Cells
Creators: name: Cromwell, Evan F.
name: Hesley, Jayne
name: Rusyn, Ivan
name: Sirenko, Oksana
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Development of predictive in vitro assays for early toxicity evaluation is extremely important for improving the drug development process and reducing drug attrition rates during clinical development. High-content imaging-based in vitro toxicity assays are emerging as efficient tools for safety and efficacy testing to improve drug development efficiency. In this report we have used an induced pluripotent stem cell (iPSC)–derived hepatocyte cell model having a primary tissue-like phenotype, unlimited availability, and the potential to compare cells from different individuals. We examined a number of assays and phenotypic markers and developed automated screening methods for assessing multiparameter readouts of general and mechanism-specific hepatotoxicity. Endpoints assessed were cell viability, nuclear shape, average and integrated cell area, mitochondrial membrane potential, phospholipid accumulation, cytoskeleton integrity, and apoptosis. We assayed compounds with known mechanisms of toxicity and also evaluated a diverse hepatotoxicity library of 240 compounds. We conclude that high-content automated screening assays using iPSC-derived hepatocytes are feasible, provide information about mechanisms of toxicity, and can facilitate the safety assessment of drugs and chemicals.
After Desperate Times, Still a Desperate Measure?: Pandemic and Post-Pandemic Engagement with Preprints in the Biology and Health Science Fields
Creators: name: Alanna K. Natanson
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023
Subjects: Scientometrics
Preprints
Altmetrics
COVID-19 Pandemic (2020-)

description: Although studies documented surging interest in preprints as the novel SARS-CoV-2 coronavirus spread in 2020, it is unclear how these non-peer-reviewed documents affected scientific communication after peer-reviewed research could address virus-related questions. This study examined how frequently biological and health science researchers contributed to preprint servers in 2021 and 2022, and how scholars and journalists monitored preprints, valued them in social media, and trusted them for formal publications. The study evaluated bibliometric and altmetric indicators for preprints posted during July 2018-December 2019, January 2020-June 2021, and July 2021-December 2022 and for coronavirus-related preprints versus non-coronavirus-related preprints. Indicators of participation, attention, and trust dropped significantly between January 2020-June 2021 and July 2021-December 2022, with sharper declines for coronavirus-related preprints. However, participation, attention, and journalist trust remained above July 2018-December 2019 rates. Preprints can still indicate attitude and behavioral shifts within a knowledge community for librarians supporting scientists and domain analysis researchers.
Development of a Cell-Based Fluorescence Polarization Biosensor Using Preproinsulin to Identify Compounds That Alter Insulin Granule Dynamics
Creators: name: Caligan, Thomas B.
name: He, Qingping
name: Smith, Ginger R.
name: Forsberg, Lawrence J.
name: Sexton, Jonathan Z.
name: Brenman, Jay E.
name: Yi, Na Young
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: Diabetes currently affects 9.3% of the U.S. population totaling $245 billion annually in U.S. direct and indirect healthcare costs. Current therapies for diabetes are limited in their ability to control blood glucose and/or enhance insulin sensitivity. Therefore, innovative and efficacious therapies for diabetes are urgently needed. Herein we describe a fluorescent insulin reporter system (preproinsulin-mCherry, PPI-mCherry) that tracks live-cell insulin dynamics and secretion in pancreatic β-cells with utility for high-content assessment of real-time insulin dynamics. Additionally, we report a new modality for sensing insulin granule packaging in conventional high-throughput screening (HTS), using a hybrid cell-based fluorescence polarization (FP)/internal FRET biosensor using the PPI-mCherry reporter system. We observed that bafilomycin, a vacuolar H+ ATPase inhibitor and inhibitor of insulin granule formation, significantly increased mCherry FP in INS-1 cells with PPI-mCherry. Partial least squares regression analysis demonstrated that an increase of FP by bafilomycin is significantly correlated with a decrease in granularity of PPI-mCherry signal in the cells. The increased FP by bafilomycin is due to inhibition of self-Förster resonant energy transfer (homo-FRET) caused by the increased mCherry intermolecular distance. FP substantially decreases when insulin is tightly packaged in the granules, and the homo-FRET decreases when insulin granule packaging is inhibited, resulting in increased FP. We performed pilot HTS of 1782 FDA-approved small molecules and natural products from Prestwick and Enzo chemical libraries resulting in an overall Z′-factor of 0.52 ± 0.03, indicating the suitability of this biosensor for HTS. This novel biosensor enables live-cell assessment of protein–protein interaction/protein aggregation in live cells and is compatible with conventional FP plate readers.
Anatomical differences and atherosclerosis in apolipoprotein E-deficient mice with 129/SvEv and C57BL/6 genetic backgrounds
Creators: name: Kim, Shinja
name: Hagaman, John
name: Johnson, Lance
name: Maeda, Nobuyo
name: Friedman, Morton
name: Reddick, Robert
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: There are well-known genetic background effects on atherosclerosis susceptibility in mice. To study the basis of these effects, we have generated the apolipoprotein E-null mutation in mouse embryonic stem cells of 129/SvEv origin, maintained it in the inbred strain (129-apoE), and compared these mice with those previously made in strain 129/Ola and backcrossed to a C57BL/6 genetic background (B6-apoE). Plasma cholesterol and triglyceride levels in the apoE-129 mice are twice the levels in apoE-B6, and both VLDL/chylomicron remnants and HDL particles are increased. Regression analysis of plaque size relative to the age of mice suggests that the initiation of atherosclerotic plaque development at the aortic root is slower in 129-apoE mice (intercept at 3.9 mo in females and 4.1 mo in males) than in B6-apoE mice (1.3 mo in females and 2.8 mo in males). In contrast, 129-apoE mice develop extensive plaques in the aortic arches earlier than B6-apoE mice. Distinct differences in the geometry of the aortic arch between the two strains suggest that anatomical differences may contribute to the effects of genetic background on atherosclerosis. The 129-apoE/B6-apoE pair thus provides a tool to study factors governing the relation between arterial geometry and the location of plaque development.
Assessment of pre- and post-methionine load homocysteine for prediction of recurrent stroke and coronary artery disease in the Vitamin Intervention for Stroke Prevention Trial
Creators: name: Howard, Virginia J.
name: Pettigrew, Luther C.
name: Toole, James F.
name: Bang, Heejung
name: Chambless, Lloyd E.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Methionine (Met) loading increases total plasma homocysteine (tHcy) and assesses homocysteine metabolism. We tested the hypothesis that pre- or post-Met tHcy will predict recurrent stroke or coronary artery disease (CAD) in a subgroup analysis of the Vitamin Intervention for Stroke Prevention (VISP) trial. VISP subjects with non-disabling stroke underwent measurement of tHcy at baseline (fasting pre- and post-Met load) and were randomized to high/low-dose B-vitamin therapy for prevention of recurrent stroke or CAD. In the sample cohort of 2,124 subjects, mean ± SD tHcy levels in µmol/L were: pre-Met 13.2 ± 4.3, post-Met 30.4 ± 9.76, and pre/post-Met Δ 17.1 ± 8.3. The hazard ratio (HR) for recurrent stroke was 1.16 (p=0.026) for 1 SD higher pre-Met tHcy and 1.15 (p=0.054) for 1 SD higher post-Met tHcy. For CAD, the HR for 1 SD higher pre-Met tHcy was 1.27 (p=0.001) and was 1.00 (p=0.99) for post-Met tHcy. In survival analyses using pre- or post-Met as covariates, the coefficient of pre/post-Met Δ was not significant for stroke and was only marginally significant for CAD (p<0.08), but was negative. We conclude that fasting, pre-Met tHcy is as effective as post-Met tHcy or pre/post-Met Δ in predicting the risk for stroke and CAD.
Harmful Representations Through Good Intentions: A Content Analysis of Penn Normal Industrial and Agricultural School Fund-Raising Booklets
Creators: name: McGruder, Brianna
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2023
Subjects: African Americans
Archives
Fund raising
Segregation

description: Beginning during the dawn of Reconstruction, racially segregated land-grant colleges and normal schools took on an important role in perpetuating racial segregation throughout the United States. This content analysis employed Critical Race Theory (CRT) tenets and primary document research to assess the representations of the Negro problem and the new Negro within Penn Normal Industrial and Agricultural School (PNIAS) fund-raising booklets, part of the Penn School Papers archival collection within Wilson Special Collections Library. The research yielded harmful representations of PNIAS students and larger populations of Gullah and Geechee citizens of St. Helena Island. Emergent themes of white self-interest, paternalist racism, trivialization, and deflection emerged.
Common variants in the CRP gene in relation to longevity and cause-specific mortality in older adults: The Cardiovascular Health Study
Creators: name: Psaty, Bruce M.
name: Lange, Leslie A.
name: Tracy, Russell P.
name: Diehr, Paula
name: Hindorff, Lucia A.
name: Cummings, Steven R.
name: Nievergelt, Caroline
name: Reiner, Alexander P.
name: Kwok, Pui
name: Walston, Jeremy
name: Newman, Anne B.
name: Halder, Indrani
name: Rice, Kenneth M.
name: Ziv, Elad
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Common polymorphisms in the CRP gene are associated with plasma CRP levels in population-based studies, but associations with age-related events are uncertain. A previous study of CRP haplotypes in older adults was broadened to include longevity and cause-specific mortality (all-cause, non-cardiovascular (nonCV), and cardiovascular (CV)). Common haplotypes were inferred from four tagSNPs in 4512 whites and five tagSNPs in 812 blacks from the Cardiovascular Health Study, a longitudinal cohort of adults over age 65. Exploratory analyses addressed early versus late mortality. CRP haplotypes were not associated with all-cause mortality or longevity overall in either population, but associations with all-cause mortality differed during early and late periods. In blacks, the haplotype tagged by 3872A (rs1205) was associated with increased risk of nonCV mortality, relative to other haplotypes (adjusted hazard ratio for each additional copy: 1.42, 95% CI: 1.07, 1.87). Relative to other haplotypes, this haplotype was associated with decreased risk of early but not decreased risk of late CV mortality in blacks; among whites, a haplotype tagged by 2667C (rs1800947) gave similar but nonsignificant findings. If confirmed, CRP genetic variants may be weakly associated with CV and nonCV mortality in older adults, particularly in self-identified blacks.
Genetic variation at the LDL receptor and HMG-CoA reductase gene loci, lipid levels, statin response, and cardiovascular disease incidence in PROSPER
Creators: name: Maeda, Nobuyo
name: Schaefer, Ernst J.
name: Shepherd, James
name: Robertson, Michele
name: Buckley, Brendan M.
name: Peter, Inga
name: Packard, Christopher
name: McMahon, Alex D.
name: Muallem, Hind
name: Jukema, J. Wouter
name: de Craen, Anton J.M.
name: Ordovas, Jose M.
name: Polisecki, Eliana
name: Ford, Ian
name: Westendorp, Rudi G.J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Our purpose was to evaluate associations of single nucleotide polymorphisms (SNPs) at the low density lipoprotein (LDL) receptor (LDLR C44857T, minor allele frequency (MAF) 0.26, and A44964G, MAF 0.25, both in the untranslated region) and HMG-CoA reductase (HMGCR i18T>G, MAF 0.019) gene loci with baseline lipid values, statin induced LDL- cholesterol (C) lowering response, and incident coronary heart disease (CHD) and cardiovascular disease on trial (CVD). Our population consisted of 5804 elderly men and women with vascular disease or one or more vascular disease risk factors, who were randomly allocated to pravastatin or placebo. Other risk factors and apolipoprotein (apo) E phenotype were controlled for in the analysis. Despite a prior report, no relationships with the HMGCR SNP were noted. For the LDLR SNPs C44857T and A44964G we noted significant associations of the rare alleles with baseline LDL-C and triglyceride levels, a modest association of the C44857T with LDL-C lowering to pravastatin in men, and significant associations with incident CHD and CVD of both SNPs, especially in men on pravastatin. Our data indicate that genetic variation at the LDLR locus can affect baseline lipids, response to pravastatin, and CVD risk in subjects placed on statin treatment.
Genetic reduction of lipoic acid synthase expression modestly increases atherosclerosis in male, but not in female, apolipoprotein E-deficient mice
Creators: name: Kim, Kuikwon
name: Kim, Hyung-Suk
name: Xu, Longquan
name: Yi, Xianwen
name: Maeda, Nobuyo
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: To evaluate the effects of a genetic reduction of Lias gene expression on atherosclerosis development.
Evolution of Vacuum Fluctuations of an Ultra-Light Massive Scalar Field generated during and before Inflation
Creators: name: Aoki, Hajime
name: Iso, Satoshi
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider an ultra-light scalar field with a mass comparable to (or lighter than) the Hubble parameter of the present universe, and calculate the time evolution of the energy-momentum tensor of the vacuum fluctuations generated during and before inflation until the late-time radiation-dominated and matter-dominated universe. The equation of state changes from $w=1/3$ in the early universe to $w=-1$ at present, and it can give a candidate for the dark energy that we observe today. It then oscillates between $w=-1$ and $1$ with the amplitude of the energy density decaying as $a^{-3}$. If the fluctuations are generated during ordinary inflation with the Hubble parameter $H_I \lesssim 10^{-5} M_{\rm Pl}$, where $M_{\rm Pl}$ is the reduced Planck scale, we need a very large e-folding number $N \gtrsim 10^{12}$ to explain the present dark energy of the order of $10^{-3} {\rm eV}$. If a Planckian universe with a large Hubble parameter $H_P \sim M_{\rm Pl}$ existed before the ordinary inflation, an e-folding number $N \sim 240$ of the Planckian inflation is sufficient.
description: 36 pages, 6 figures; v2:version publisehd in PTEP
Longitudinal association between toenail selenium levels and measures of subclinical atherosclerosis: The CARDIA trace element study
Creators: name: Daviglus, Martha L.
name: Liu, Kiang
name: Xun, Pengcheng
name: He, Ka
name: Morris, J. Steven
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: To examine the longitudinal association between toenail selenium levels and sub-clinical atherosclerosis over an 18-year period.