cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Loop Quantum Cosmology with Complex Ashtekar Variables
Creators: name: Achour, Jibril Ben
name: Grain, Julien
name: Noui, Karim
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct and study Loop Quantum Cosmology (LQC) when the Barbero-Immirzi parameter takes the complex value $γ=\pm i$. We refer to this new quantum cosmology as complex Loop Quantum Cosmology. We proceed in making an analytic continuation of the Hamiltonian constraint (with no inverse volume corrections) from real $γ$ to $γ=\pm i$ in the simple case of a flat FLRW Universe coupled to a massless scalar field with no cosmological constant. For that purpose, we first compute the non-local curvature operator (defined by the trace of the holonomy of the connection around a fundamental plaquette) evaluated in any spin $j$ representation and we find a new close formula for it. This allows to define explicitly a one parameter family of regularizations of the Hamiltonian constraint in LQC, parametrized by the spin $j$. It is immediate to see that any spin $j$ regularization leads to a bounce scenario. Then, motivated particularly by previous results on black hole thermodynamics, we perform the analytic continuation of the Hamiltonian constraint defined by $γ=\pm i$ and $j=-1/2+is$ where $s$ is real. Even if the area spectrum is now continuous, we show that the so-defined complex LQC removes also the original singularity which is replaced by a quantum bounce. In addition, the maximal density and the minimal volume of the Universe are obviously independent of $γ$. Furthermore, the dynamics before and after the bounce are no more symmetric, which makes a clear distinction between these two phases of the evolution of the Universe.
description: 22 pages
Respiratory Syncytial Virus Grown in Vero Cells Contains a Truncated Attachment Protein That Alters Its Infectivity and Dependence on Glycosaminoglycans
Creators: name: Pickles, R. J.
name: Peeples, M. E.
name: Zhang, L.
name: Kwilas, S.
name: Walsh, E.
name: Liesman, R. M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: Human respiratory syncytial virus (RSV) contains a heavily glycosylated 90-kDa attachment glycoprotein (G). Infection of HEp-2 and Vero cells in culture depends largely on virion G protein binding to cell surface glycosaminoglycans (GAGs). This GAG-dependent phenotype has been described for RSV grown in HEp-2 cells, but we have found that it is greatly reduced by a single passage in Vero cells. Virions produced from Vero cells primarily display a 55-kDa G glycoprotein. This smaller G protein represents a post-Golgi compartment form that is lacking its C terminus, indicating that the C terminus is required for GAG dependency. Vero cell-grown virus infected primary well-differentiated human airway epithelial (HAE) cell cultures 600-fold less efficiently than did HEp-2 cell-grown virus, indicating that the C terminus of the G protein is also required for virus attachment to this model of the in vivo target cells. This reduced infectivity for HAE cell cultures is not likely to be due to the loss of GAG attachment since heparan sulfate, the primary GAG used by RSV for attachment to HEp-2 cells, is not detectable at the apical surface of HAE cell cultures where RSV enters. Growing RSV stocks in Vero cells could dramatically reduce the initial infection of the respiratory tract in animal models or in volunteers receiving attenuated virus vaccines, thereby reducing the efficiency of infection or the efficacy of the vaccine.
Suppression of Human Immunodeficiency Virus Type 1 (HIV-1) Viremia with Reverse Transcriptase and Integrase Inhibitors, CD4+ T-Cell Recovery, and Viral Rebound upon Interruption of Therapy in a New Model for HIV Treatment in the Humanized Rag2-/- c-/- Mouse
Creators: name: Choudhary, S. K.
name: Ince, W. L.
name: Margolis, D. M.
name: Kashuba, A. D. M.
name: Swanstrom, R.
name: Cheema, M.
name: Zhang, L.
name: Rezk, N. L.
name: Su, L.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: A small animal model that reproduces human immunodeficiency virus type 1 (HIV-1) pathogenesis may allow modeling of new therapeutic strategies in ways not approachable in mononuclear cell culture. We find that, as in humans, combination antiretroviral therapy (ART) in humanized (hu-) Rag2−/−γc−/− mice allows suppression of viremia below the limits of detection and recovery of CD4+ cells, while interruption of ART results in viral rebound and renewed loss of CD4+ T cells. Failure of ART in infected mice is associated with the appearance of drug resistance mutations. The hu-Rag2−/−γc−/− mouse may therefore facilitate testing of novel approaches to HIV replication and persistence.
The Epstein-Barr Virus (EBV) Deubiquitinating Enzyme BPLF1 Reduces EBV Ribonucleotide Reductase Activity
Creators: name: Bentz, G. L.
name: Pagano, J. S.
name: Shackelford, J.
name: Ning, S.
name: Whitehurst, C. B.
name: Langelier, Y.
name: Dufour, F.
name: Gershburg, E.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: A newly discovered virally encoded deubiquitinating enzyme (DUB) is strictly conserved across the Herpesviridae. Epstein-Barr virus (EBV) BPLF1 encodes a tegument protein (3,149 amino acids) that exhibits deubiquitinating (DUB) activity that is lost upon mutation of the active-site cysteine. However, targets for the herpesviral DUBs have remained elusive. To investigate a predicted interaction between EBV BPLF1 and EBV ribonucleotide reductase (RR), a functional clone of the first 246 N-terminal amino acids of BPLF1 (BPLF1 1-246) was constructed. Immunoprecipitation verified an interaction between the small subunit of the viral RR2 and BPLF1 proteins. In addition, the large subunit (RR1) of the RR appeared to be ubiquitinated both in vivo and in vitro; however, ubiquitinated forms of the small subunit, RR2, were not detected. Ubiquitination of RR1 requires the expression of both subunits of the RR complex. Furthermore, coexpression of RR1 and RR2 with BPLF1 1-246 abolishes ubiquitination of RR1. EBV RR1, RR2, and BPLF1 1-246 colocalized to the cytoplasm in HEK 293T cells. Finally, expression of enzymatically active BPLF1 1-246 decreased RR activity, whereas a nonfunctional active-site mutant (BPLF1 C61S) had no effect. These results indicate that the EBV deubiquitinating enzyme interacts with, deubiquitinates, and influences the activity of the EBV RR. This is the first verified protein target of the EBV deubiquitinating enzyme.
Expressive Power and Approximation Errors of Restricted Boltzmann Machines
Creators: name: Montufar, Guido
name: Rauh, Johannes
name: Ay, Nihat
Publisher: name: arXiv
Year: 2014
Subjects: subject: Machine Learning (stat.ML)
subject: Probability (math.PR)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics
subject: 82C32, 68Q99

description: We present explicit classes of probability distributions that can be learned by Restricted Boltzmann Machines (RBMs) depending on the number of units that they contain, and which are representative for the expressive power of the model. We use this to show that the maximal Kullback-Leibler divergence to the RBM model with $n$ visible and $m$ hidden units is bounded from above by $n - \left\lfloor \log(m+1) \right\rfloor - \frac{m+1}{2^{\left\lfloor\log(m+1)\right\rfloor}} \approx (n -1) - \log(m+1)$. In this way we can specify the number of hidden units that guarantees a sufficiently rich model containing different classes of distributions and respecting a given error tolerance.
description: 9 pages, 3 figures, plus 1 page, 1 figure appendix, minor corrections of the first publication
Geometric spin manipulation in semiconductor quantum dots
Creators: name: Prabhakar, Sanjay
name: Melnik, Roderick
name: Inomata, Akira
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We propose a method to flip the spin completely by an adiabatic transport of quantum dots. We show that it is possible to flip the spin by inducing a geometric phase on the spin state of a quantum dot. We estimate the geometric spin flip time (approximately 2 pico-sec) which turned out to be much shorter than the experimentally reported decoherence time (approx. 100 nano-sec) that would provide an alternative means of fliping the spin before reaching decoherence. It is important that both the Rashba coupling and the Dresselhaus coupling are present for inducing a phase necessary for spin flip. If one of them is absent, the induced phase is trivial and irrelevant for spin-flip.
description: 4 pages, 3 figures
The time delay in strong gravitational lensing with Gauss-Bonnet correction
Creators: name: Man, Jingyun
name: Cheng, Hongbo
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The time delay between two relativistic images in the strong gravitational lensing governed by Gauss-Bonnet gravity is studied. We derive and calculate the expression of time delay due to the Gauss-Bonnet coupling. It is shown that the time delay for two images with larger space each other is longer. We also find that the ratio of Gauss-Bonnet coefficient and the mass of gravitational source changes in the region like $\fracα{M}\in[0,2)$. The time delay is divergent with $\fracα{M}\longrightarrow 2$.
description: 9 pages, 1 figure
The Heptad Repeat 2 Domain Is a Major Determinant for Enhanced Human Immunodeficiency Virus Type 1 (HIV-1) Fusion and Pathogenicity of a Highly Pathogenic HIV-1 Env
Creators: name: Zhang, L.
name: Su, L.
name: Sivaraman, V.
name: Jeffrey, J. L.
name: Meissner, E. G.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: Human immunodeficiency virus type 1 (HIV-1)-mediated depletion of CD4+ lymphocytes in an infected individual is the hallmark of progression to AIDS. However, the mechanism for this depletion remains unclear. To identify mechanisms of HIV-1-mediated CD4 T-cell death, two similar viral isolates obtained from a rapid progressor patient with significantly different pathogenic phenotypes were studied. One isolate (R3A) demonstrates enhanced pathogenesis in both in vivo models and relevant ex vivo lymphoid organ model systems compared to another isolate, R3B. The pathogenic determinants were previously mapped to the V5-gp41 envelope region, correlating functionally with enhanced fusion activity and elevated CXCR4 binding affinity. To further elucidate specific differences between R3A and R3B within the V5-gp41 domains that enhance CD4 depletion, R3A-R3B chimeras to study the V5-gp41 region were developed. Our data demonstrate that six residues in the ectodomain of R3A provide the major determinant for both enhanced Env-cell fusion and pathogenicity. Furthermore, three amino acid differences in the heptad repeat 2 (HR-2) domain of R3A determined its fusion activity and significantly elevated its pathogenic activity. The chimeric viruses with enhanced fusion activity, but not elevated CXCR4 affinity, correlated with high pathogenicity in the thymus organ. We conclude that the functional domain of a highly pathogenic HIV-1 Env is determined by mutations in the HR-2 region that contribute to enhanced fusion and CD4 T-cell depletion.
Non-oscillatory flux correlation functions for efficient nonadiabatic rate theory
Creators: name: Richardson, Jeremy O.
name: Thoss, Michael
Publisher: name: arXiv
Year: 2014
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: There is currently much interest in the development of improved trajectory-based methods for the simulation of nonadiabatic processes in complex systems. An important goal for such methods is the accurate calculation of the rate constant over a wide range of electronic coupling strengths and it is often the nonadiabatic, weak-coupling limit, which being far from the Born-Oppenheimer regime, provides the greatest challenge to current methods. We show that in this limit there is an inherent sign problem impeding further development which originates from the use of the usual quantum flux correlation functions, which can be very oscillatory at short times. From linear response theory, we derive a modified flux correlation function for the calculation of nonadiabatic reaction rates, which still rigorously gives the correct result in the long-time limit regardless of electronic coupling strength, but unlike the usual formalism is not oscillatory in the weak-coupling regime. In particular, a trajectory simulation of the modified correlation function is naturally initialized in a region localized about the crossing of the potential energy surfaces. In the weak-coupling limit, a simple link can be found between the dynamics initialized from this transition-state region and an generalized quantum golden-rule transition-state theory, which is equivalent to Marcus theory in the classical harmonic limit. This new correlation function formalism thus provides a platform on which a wide variety of dynamical simulation methods can be built aiding the development of accurate nonadiabatic rate theories applicable to complex systems.
description: Submitted to the Journal of Chemical Physics. 16 pages with 5 figures
Transcriptional Downregulation of p27KIP1 through Regulation of E2F Function during LMP1-Mediated Transformation
Creators: name: Mainou, B. A.
name: Raab-Traub, N.
name: Everly, D. N.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: LMP1 induces the phenotypic transformation of fibroblasts and affects regulators of the cell cycle during this process. LMP1 decreases expression of the cyclin-dependent kinase inhibitor p27 and increases the levels and phosphorylation of cyclin-dependent kinase 2 and the retinoblastoma protein. In the present study, the effects of LMP1 on cell cycle progression and the mechanism of p27 downregulation by LMP1 were determined. Although p27 is frequently regulated at the posttranscriptional level during cell cycle progression and in cancer, LMP1 did not decrease ectopically expressed p27. However, LMP1 did decrease p27 RNA levels and inhibited the activity of p27 promoter reporters. The LMP1-regulated promoter element was mapped to a region containing two E2F sites. Electrophoretic mobility shift assays determined that the regulated cis element bound an inhibitory E2F complex containing E2F4 and p130. These findings indicate that LMP1 decreases p27 transcription through effects on E2F family transcription factors. This property likely contributes to the ability of LMP1 to stimulate cell cycle progression.
Classifying invariant $σ$-ideals with analytic base on good Cantor measure spaces
Creators: name: Banakh, Taras
name: Ralowski, Robert
name: Zeberski, Szymon
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Topology (math.GN)
subject: Dynamical Systems (math.DS)
subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03E15, 28A05, 28D05, 54H05

description: Let $X$ be a zero-dimensional compact metrizable space endowed with a strictly positive continuous Borel $σ$-additive measure $μ$ which is good in the sense that for any clopen subsets $U,V\subset X$ with $μ(U)
description: 10 pages
Venezuelan Equine Encephalitis Virus Disrupts STAT1 Signaling by Distinct Mechanisms Independent of Host Shutoff
Creators: name: Heise, M. T.
name: Whitmore, A. C.
name: Montgomery, S. A.
name: White, L. J.
name: Morrison, T. E.
name: Johnston, R. E.
name: Simmons, J. D.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: Venezuelan equine encephalitis virus (VEEV) is an important human and veterinary pathogen causing sporadic epizootic outbreaks of potentially fatal encephalitis. The type I interferon (IFN) system plays a central role in controlling VEEV and other alphavirus infections, and IFN evasion is likely an important determinant of whether these viruses disseminate and cause disease within their hosts. Alphaviruses are thought to limit the induction of type I IFNs and IFN-stimulated genes by shutting off host cell macromolecular synthesis, which in the case of VEEV is partially mediated by the viral capsid protein. However, more specific strategies by which alphaviruses inhibit type I IFN signaling have not been characterized. Analyses of cells infected with VEEV and VEEV replicon particles (VRP) demonstrate that viral infection rapidly disrupts tyrosine phosphorylation and nuclear translocation of the transcription factor STAT1 in response to both IFN-β and IFN-γ. This effect was independent of host shutoff and expression of viral capsid, suggesting that VEEV uses novel mechanisms to interfere with type I and type II IFN signaling. Furthermore, at times when STAT1 activation was efficiently inhibited, VRP infection did not limit tyrosine phosphorylation of Jak1, Tyk2, or STAT2 after IFN-β treatment but did inhibit Jak1 and Jak2 activation in response to IFN-γ, suggesting that VEEV interferes with STAT1 activation by the type I and II receptor complexes through distinct mechanisms. Identification of the viral requirements for this novel STAT1 inhibition will further our understanding of alphavirus molecular pathogenesis and may provide insights into effective alphavirus-based vaccine design.
A Determinant of Sindbis Virus Neurovirulence Enables Efficient Disruption of Jak/STAT Signaling
Creators: name: Wollish, A. C.
name: Simmons, J. D.
name: Heise, M. T.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Previous studies with Venezuelan equine encephalitis virus and Sindbis virus (SINV) indicate that alphaviruses are capable of suppressing the cellular response to type I and type II interferons (IFNs) by disrupting Jak/STAT signaling; however, the relevance of this signaling inhibition toward pathogenesis has not been investigated. The relative abilities of neurovirulent and nonneurovirulent SINV strains to downregulate Jak/STAT signaling were compared to determine whether the ability to inhibit IFN signaling correlates with virulence potential. The adult mouse neurovirulent strain AR86 was found to rapidly and robustly inhibit tyrosine phosphorylation of STAT1 and STAT2 in response to IFN-γ and/or IFN-β. In contrast, the closely related SINV strains Girdwood and TR339, which do not cause detectable disease in adult mice, were relatively inefficient inhibitors of STAT1/2 activation. Decreased STAT activation in AR86-infected cells was associated with decreased activation of the IFN receptor-associated tyrosine kinases Tyk2, Jak1, and Jak2. To identify the viral factor(s) involved, we infected cells with several panels of AR86/Girdwood chimeric viruses. Surprisingly, we found that a single amino acid determinant, threonine at nsP1 position 538, which is required for AR86 virulence, was also required for efficient disruption of STAT1 activation, and this determinant fully restored STAT1 inhibition when it was introduced into the avirulent Girdwood background. These data indicate that a key virulence determinant plays a critical role in downregulating the response to type I and type II IFNs, which suggests that the ability of alphaviruses to inhibit Jak/STAT signaling relates to their in vivo virulence potential.
A Multivalent Vaccination Strategy for the Prevention of Old World Arenavirus Infection in Humans
Creators: name: Sidney, J.
name: Buchmeier, M. J.
name: Barrowman, P.
name: Whitton, J. L.
name: Alexander, J.
name: Whitmire, J. K.
name: Kotturi, M. F.
name: Botten, J.
name: Sette, A.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Arenaviruses cause severe human disease ranging from aseptic meningitis following lymphocytic choriomeningitis virus (LCMV) infection to hemorrhagic fever syndromes following infection with Guanarito virus (GTOV), Junin virus (JUNV), Lassa virus (LASV), Machupo virus (MACV), Sabia virus (SABV), or Whitewater Arroyo virus (WWAV). Cellular immunity, chiefly the CD8+ T-cell response, plays a critical role in providing protective immunity following infection with the Old World arenaviruses LASV and LCMV. In the current study, we evaluated whether HLA class I-restricted epitopes that are cross-reactive among pathogenic arenaviruses could be identified for the purpose of developing an epitope-based vaccination approach that would cross-protect against multiple arenaviruses. We were able to identify a panel of HLA-A*0201-restricted peptides derived from the same region of the glycoprotein precursor (GPC) of LASV (GPC spanning residues 441 to 449 [GPC441-449]), LCMV (GPC447-455), JUNV (GPC429-437), MACV (GPC444-452), GTOV (GPC427-435), and WWAV (GPC428-436) that displayed high-affinity binding to HLA-A*0201 and were recognized by CD8+ T cells in a cross-reactive manner following LCMV infection or peptide immunization of HLA-A*0201 transgenic mice. Immunization of HLA-A*0201 mice with the Old World peptide LASV GPC441-449 or LCMV GPC447-455 induced high-avidity CD8+ T-cell responses that were able to kill syngeneic target cells pulsed with either LASV GPC441-449 or LCMV GPC447-455in vivo and provided significant protection against viral challenge with LCMV. Through this study, we have demonstrated that HLA class I-restricted, cross-reactive epitopes exist among diverse arenaviruses and that individual epitopes can be utilized as effective vaccine determinants for multiple pathogenic arenaviruses.
Higgs-boson production through gluon fusion at NNLO QCD with parton showers
Creators: name: Höche, Stefan
name: Li, Ye
name: Prestel, Stefan
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss how the UN2LOPS scheme for matching NNLO calculations to parton showers can be applied to processes with large higher-order perturbative QCD corrections. We focus on Higgs-boson production through gluon fusion as an example. We also present an NNLO fixed-order event generator for this reaction.
description: 9 pages, 3 figures, 1 table
Compartmentalization and Clonal Amplification of HIV-1 Variants in the Cerebrospinal Fluid during Primary Infection
Creators: name: Spudich, S.
name: Swanstrom, R.
name: Price, R. W.
name: Schnell, G.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Human immunodeficiency virus type 1 (HIV-1)-associated dementia (HAD) is a severe neurological disease that affects a subset of HIV-1-infected individuals. Increased compartmentalization has been reported between blood and cerebrospinal fluid (CSF) HIV-1 populations in subjects with HAD, but it is still not known when compartmentalization arises during the course of infection. To assess HIV-1 genetic compartmentalization early during infection, we compared HIV-1 populations in the peripheral blood and CSF in 11 primary infection subjects, with analysis of longitudinal samples over the first 18 months for a subset of subjects. We used heteroduplex tracking assays targeting the variable regions of env and single-genome amplification and sequence analysis of the full-length env gene to identify CSF-compartmentalized variants and to examine viral genotypes within the compartmentalized populations. For most subjects, HIV-1 populations were equilibrated between the blood and CSF compartments. However, compartmentalized HIV-1 populations were detected in the CSF of three primary infection subjects, and longitudinal analysis of one subject revealed that compartmentalization during primary HIV-1 infection was resolved. Clonal amplification of specific HIV-1 variants was identified in the CSF population of one primary infection subject. Our data show that compartmentalization can occur in the central nervous system (CNS) of subjects in primary HIV-1 infection in part through persistence of the putative transmitted parental variant or via viral genetic adaptation to the CNS environment. The presence of distinct HIV-1 populations in the CSF indicates that independent HIV-1 replication can occur in the CNS, even early after HIV-1 transmission.
title: Parental consent for newborn screening: a discrete choice experiment
Creators: name: Liao, Yifu
Publisher: name: Memorial University of Newfoundland
Year: 2021

description: Background: Parental consent is very commonly assumed for newborn bloodspot screening (NBS) in most Canadian provincial screening programs. This falls short of usual norms, and evidence suggests that some parents would prefer an explicit process. This study was designed to inform improvements in NBS consent processes. Objectives: (1) To examine parents’ past experiences with, and attitudes towards, NBS consent processes in Canada. (2) To quantify parents’ preferences towards specific attributes of the NBS consent process, and identify characteristics of subgroups with different preference patterns. Method: A cross-sectional survey that included a discrete choice experiment (DCE) was conducted to capture information on participants’ past experiences with and preferences for NBS consent processes. DCE data were analyzed using conditional logit and latent class (LC) regression models. Results: The sample comprised 715 participants. As an overall group, respondents preferred to have NBS information provided late in pregnancy, for consent not to be assumed by providers, and for the consent decision to always be recorded. Three classes of participants with different underlying preference patterns were identified in the sample. Conclusion: If NBS programs wish to better meet parents’ preferenes, the results indicate specific aspects of the consent process that could be targeted for further examination..
Distinct p53, p53:LANA, and LANA Complexes in Kaposi's Sarcoma-Associated Herpesvirus Lymphomas
Creators: name: Chen, W.
name: Hilton, I. B.
name: Burd, C. E.
name: Dittmer, D. P.
name: Staudt, M. R.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: The role of p53 in primary effusion lymphoma (PEL) is complicated. The latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) binds p53. Despite this interaction, we had found that p53 was functional in PEL, i.e., able to induce apoptosis in response to DNA damage (C. E. Petre, S. H. Sin, and D. P. Dittmer, J. Virol. 81:1912-1922, 2007), and that hdm2 was overexpressed. To further elucidate the relationship between LANA, p53, and hdm2, we purified LANA complexes from PEL by column chromatography. This confirmed that LANA bound p53. However, the LANA:p53 complexes were a minority compared to hdm2:p53 and p53:p53 complexes. The half-life of p53 was not extended, which is in contrast to the half-life of simian virus 40 T antigen-transformed cells. p53:p53, LANA:p53, and LANA:LANA complexes coexisted in PEL, and each protein was able to bind to its cognate DNA element. These data suggest that under normal conditions, p53 is inactive in PEL, thus allowing for exponential growth, but that this inactivation is driven by the relative stoichiometries of LANA, hdm2, and p53. If p53 is activated by DNA damage or nutlin-3a, the complex falls apart easily, and p53 exercises its role as guardian of the genome.
Cold Water Vapor in the Barnard 5 Molecular Cloud
Creators: name: Wirström, E. S.
name: Charnley, S. B.
name: Persson, C. M.
name: Buckle, J. V.
name: Cordiner, M. A.
name: Takakuwa, S.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: After more than 30 years of investigations, the nature of gas-grain interactions at low temperatures remains an unresolved issue in astrochemistry. Water ice is the dominant ice found in cold molecular clouds, however, there is only one region where cold (~10 K) water vapor has been detected - L1544. This study aims to shed light on ice desorption mechanisms under cold cloud conditions by expanding the sample. The clumpy distribution of methanol in dark clouds testifies to transient desorption processes at work -- likely to also disrupt water ice mantles. Therefore, the Herschel HIFI instrument was used to search for cold water in a small sample of prominent methanol emission peaks. We report detections of the ground-state transition of o-H2O (J = 1_10 - 1_01) at 556.9360 GHz toward two positions in the cold molecular cloud Barnard 5. The relative abundances of methanol and water gas support a desorption mechanism which disrupts the outer ice mantle layers, rather than causing complete mantle removal.
description: 10 pages, 2 figures
Epstein-Barr Virus Latent Membrane Protein 1 Modulates Distinctive NF- B Pathways through C-Terminus-Activating Region 1 To Regulate Epidermal Growth Factor Receptor Expression
Creators: name: Kung, C.-P.
name: Raab-Traub, N.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Epstein-Barr Virus (EBV) latent membrane protein 1 (LMP1) is required for EBV B-lymphocyte transformation, transforms rodent fibroblasts, and can induce lymphoma and epithelial hyperplasia in transgenic mice. Two domains have been identified within the intracellular carboxy terminus that can activate NF-κB, C-terminus-activating region 1 (CTAR1) and CTAR2, through interactions with tumor necrosis receptor-associated factors (TRAFs). CTAR1 can activate both the canonical and noncanonical NF-κB pathways and has unique effects on cellular gene expression. The epidermal growth factor receptor (EGFR) is highly induced by LMP1-CTAR1 in epithelial cells through activation of a novel NF-κB form containing p50 homodimers and Bcl-3. To further understand the regulation of NF-κB in CTAR1-induced EGFR expression, we evaluated the ability of CTAR1 to induce EGFR in mouse embryonic fibroblasts (MEFs) defective for different NF-κB effectors. CTAR1-mediated EGFR induction required the NF-κB-inducing kinase (NIK) but not the IκB kinase (IKK) complex components that regulate canonical or noncanonical NF-κB pathways. CTAR1-mediated induction of nuclear p50 occurred in IKKβ-, IKKγ-, and NIK-defective MEFs, indicating that this induction is not dependent on the canonical or noncanonical NF-κB pathways. EGFR and nuclear p50 were expressed at high levels in TRAF2−/− fibroblasts and were not induced by CTAR1. In TRAF3−/− MEFs, CTAR1 induced nuclear p50 but did not affect basal levels of STAT3 serine phosphorylation or induce EGFR expression. EGFR was induced by LMP1 in TRAF6−/− MEFs. These findings suggest that this novel NF-κB pathway is differentially regulated by TRAF2 and TRAF3, and that distinct interactions of LMP1 and its effectors regulate LMP1-mediated gene expression.
Evolution of the HIV-1 env Gene in the Rag2-/-  C-/- Humanized Mouse Model
Creators: name: Zhang, L.
name: Su, L.
name: Ince, W. L.
name: Jiang, Q.
name: Swanstrom, R.
name: Arrildt, K.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Rag2−/− γC−/− mice transplanted with human hematopoietic stem cells (DKO-hu-HSC mice) mimic aspects of human infection with human immunodeficiency virus type 1 (HIV-1), including sustained viral replication and CD4+ T-cell decline. However, the extent of HIV-1 evolution during long-term infection in these humanized mice, a key feature of the natural infection, has not been assessed fully. In this study, we examined the types of genotypic and phenotypic changes in the viral env gene that occur in the viral populations of DKO-hu-HSC mice infected with the CCR5-tropic isolate HIV-1JRCSF for up to 44 weeks. The mean rate of divergence of viral populations in mice was similar to that observed in a cohort of humans during a similar period of infection. Many amino acid substitutions were common across mice, including losses of N-linked glycosylation sites and substitutions in the CD4 binding site and in CD4-induced epitopes, indicating common selective pressures between mice. In addition, env variants evolved sensitivity to antibodies directed at V3, suggesting a more open conformation for Env. This phenotypic change was associated with increased CD4 binding efficiency and was attributed to specific amino acid substitutions. In one mouse, env variants emerged that exhibited a CXCR4-tropic phenotype. These sequences were compartmentalized in the mesenteric lymph node. In summary, viral populations in these mice exhibited dynamic behavior that included sequence evolution, compartmentalization, and the appearance of distinct phenotypic changes. Thus, humanized mice offer a useful model for studying evolutionary processes of HIV-1 in a complex host environment.
Current ESPGHAN guidelines for celiac disease in pediatric age, tertiary care center experience: a proposal for further simplification
Creators: name: Malamisura, Monica
name: Colantuono, Rossella
name: Salvati, Virginia M.
name: Croce, Roberta
name: D’Adamo, Grazia
name: Passaro, Tiziana
name: D’Angelo, Emanuela
name: Boffardi, Massimo
name: Garzi, Alfredo
name: Malamisura, Basilio
Publisher: name: Universita' degli Studi di Salerno
Year: 2019
Subjects: Celiac disease
Duodenal biopsy
Anti-tissue transglutaminase
Haplotypes

description: According to the 2012 ESPGHAN criteria for diagnosis of celiac disease (CD), duodenal biopsy (DB) can be avoided in children with a clear malabsorption syndrome, anti-tissue transglutaminase IgA (tTG2) ≥ 10x the cut-off, anti-endomysium IgA (EMA) and HLA DQ2/DQ8 genes. The aim of this study is to report our experience and evaluate the accuracy of the actual guidelines. Patients and methods: This is a retrospective study conducted on all patients diagnosed CD from 2012 to 2018 in our Center. For all patients enrolled were analyzed: data of family history, symptoms, serology, genetics, Marsh grade and follow-up. Results: A total of 481 children [mean age 6,4 yrs; F:M= 1.8:1] were included in the study. The mean age of patients who were not subject to DB was lower (4.51 yrs) comparing with patients that received DB (6.48 yrs). Out of the 256 patients with anti-tTG2 ≥ 10 fold, 121 underwent DB because of mild symptoms (84/121) or no symptoms (37/121). In all cases Marsh type 3 was found and HLA haplotypes was compatible with CD diagnosis. Conclusions: Our study confirms that the serology has a primary importance to diagnose CD, regardless of the symptoms. These data suggest that biopsy and HLA haplotypes search, in presence of anti-tTG2 IgA ≥ 10x the cut-off, are wasteful and unhelpful for the patients.
Structure of the third moment of the generalized Rosenblatt distribution
Creators: name: Bai, Shuyang
name: Taqqu, Murad S.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Probability (math.PR)
subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 60G18, 60F05

description: The Rosenblatt distribution appears as limit in non-central limit theorems. The generalized Rosenblatt distribution is obtained by allowing different power exponents in the kernel that defines the usual Rosenblatt distribution. We derive an explicit formula for its third moment, correcting the one in \citet{maejima:tudor:2012:selfsimilar} and \citet{tudor:2013:analysis}. Evaluating this formula numerically, we are able to confirm that the class of generalized Hermite processes is strictly richer than the class of Hermite processes.
Line lists for the A2PI-X2Sigma+ (red) and {B2Sigma+-X2Sigma} (violet) Systems of CN, 13C14N, and 12C15N, and Application to Astronomical Spectra
Creators: name: Sneden, Christopher
name: Lucatello, Sara
name: Ram, Ram S.
name: Brooke, James S. A.
name: Bernath, Peter
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: New red and violet system line lists for the CN isotopologues 13C14N and 12C15N have been generated. These new transition data are combined with those previously derived for 12C14N, and applied to the determination of CNO abundances in the solar photosphere and in four red giant stars: Arcturus, the bright very low-metallicity star HD 122563, and carbon-enhanced metal-poor stars HD 196944 and HD 201626. When lines of both red and violet system lines are detectable in a star, their derived N abundances are in good agreement. The mean N abundances determined in this work generally are also in accord with published values.
description: ApJS, in press, 37 pages, 7 figures, 3 tables
Approximation by boolean sums of Jackson operators on the sphere
Creators: name: Wang, Yuguang
name: Cao, Feilong
Publisher: name: arXiv
Year: 2014
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 41A17

description: This paper concerns the approximation by the Boolean sums of Jackson operators $\oplus^rJ_{k,s}(f)$ on the unit sphere $\mathbb S^{n-1}$ of $\mathbb{R}^{n}$. We prove the following the direct and inverse theorem for $\oplus^rJ_{k,s}(f)$: there are constants $C_1$ and $C_2$ such that \begin{equation*} C_1\|\oplus^rJ_{k,s}f-f\|_p \leq ω^{2r}(f,k^{-1})_p \leq C_2 \max_{v\geq k}\|\oplus^rJ_{k,s}f-f\|_p \end{equation*} for any positive integer $k$ and any $p$th Lebesgue integrable functions $f$ defined on $\mathbb S^{n-1}$, where $ω^{2r}(f,t)_p$ is the modulus of smoothness of degree $2r$ of $f$. We also prove that the saturation order for $\oplus^rJ_{k,s}$ is $k^{-2r}$.
Low-bias Negative Differential Resistance effect in armchair graphene nanoribbon junctions
Creators: name: Li, Suchun
name: Gan, Chee Kwan
name: Son, Young-Woo
name: Feng, Yuan Ping
name: Quek, Su Ying
Publisher: name: arXiv
Year: 2014
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Graphene nanoribbons with armchair edges (AGNRs) have bandgaps that can be flexibly tuned via the ribbon width. A junction made of a narrower AGNR sandwiched between two wider AGNR leads was recently reported to possess two perfect transmission channels close to the Fermi level. Here, we report that by using a bias voltage to drive these transmission channels into the gap of the wider AGNR lead, we can obtain a negative differential resistance (NDR) effect. Owing to the intrinsic properties of the AGNR junctions, the on-set bias reaches as low as ~ 0.2 V and the valley current almost vanishes. We further show that such NDR effect is robust against details of the atomic structure of the junction, substrate and whether the junction is made by etching or by hydrogenation.
description: The following article has been submitted to Applied Physics Letters (http://scitation.aip.org/content/aip/journal/apl). Copyright (2014) Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License
Heterotypic Humoral and Cellular Immune Responses following Norwalk Virus Infection
Creators: name: Johnston, R. E.
name: Donaldson, E.
name: Frelinger, J. A.
name: Weber, D. J.
name: Moe, C. L.
name: Baric, R. S.
name: Lindesmith, L. C.
name: Leon, J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Norovirus immunity is poorly understood as the limited data available on protection after infection are often contradictory. In contrast to the more prominent GII noroviruses, GI norovirus infections are less frequent in outbreaks. The GI noroviruses display very complex patterns of heterotypic immune responses following infection, and many individuals are highly susceptible to reinfection. To study the immune responses and mechanisms of GI.1 persistence, we built structural models and recombinant virus-like particles (VLPs) of five GI strains: GI.1-1968, GI.1-2001, GI.2-1999, GI.3-1999, and GI.4-2000. Structural models of four GI genotype capsid P domain dimers suggested that intragenotype structural variation is limited, that the GI binding pocket is mostly preserved between genotypes, and that a conserved, surface-exposed epitope may allow for highly cross-reactive immune responses. GI VLPs bound to histo-blood group antigens (HBGAs) including fucose, Lewis, and A antigens. Volunteers infected with GI.1-1968 (n = 10) had significant increases between prechallenge and convalescent reactive IgG for all five GI VLPs measured by enzyme immunoassay. Potential cross-neutralization of GI VLPs was demonstrated by convalescent-phase serum cross-blockade of GI VLP-HBGA interaction. Although group responses were significant for all GI VLPs, each individual volunteer demonstrated a unique VLP blockade pattern. Further, peripheral blood mononuclear cells (PBMCs) were stimulated with each of the VLPs, and secretion of gamma interferon (IFN-γ) was measured. As seen with blockade responses, IFN-γ secretion responses differed by individual. Sixty percent responded to at least one GI VLP, with only two volunteers responding to GI.1 VLP. Importantly, four of five individuals with sufficient PBMCs for cross-reactivity studies responded more robustly to other GI VLPs. These data suggest that preexposure history and deceptive imprinting may complicate PBMC and B-cell immune responses in some GI.1-1968-challenged individuals and highlight a potential complication in the design of efficacious norovirus vaccines.
A study on effectiveness of extreme learning machine
Creators: name: Wang, Yuguang
name: Cao, Feilong
name: Yuan, Yubo
Publisher: name: arXiv
Year: 2014
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Extreme learning machine (ELM), proposed by Huang et al., has been shown a promising learning algorithm for single-hidden layer feedforward neural networks (SLFNs). Nevertheless, because of the random choice of input weights and biases, the ELM algorithm sometimes makes the hidden layer output matrix H of SLFN not full column rank, which lowers the effectiveness of ELM. This paper discusses the effectiveness of ELM and proposes an improved algorithm called EELM that makes a proper selection of the input weights and bias before calculating the output weights, which ensures the full column rank of H in theory. This improves to some extend the learning rate (testing accuracy, prediction accuracy, learning time) and the robustness property of the networks. The experimental results based on both the benchmark function approximation and real-world problems including classification and regression applications show the good performances of EELM.
Identification of Cross-Reactive Norovirus CD4+ T Cell Epitopes
Creators: name: LoBue, A. D.
name: Baric, R. S.
name: Lindesmith, L. C.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Immune responses and the components of protective immunity following norovirus infection in humans are poorly understood. Although antibody responses following norovirus infection have been partially characterized, T cell responses in humans remain largely undefined. In contrast, T cells have been shown to be essential for viral clearance of mouse norovirus (MNV) infection. In this paper, we demonstrate that CD4+ T cells secrete gamma interferon (IFN-γ) in response to stimulation with MNV virus-like particles (VLPs) after MNV infection, supporting earlier reports for norovirus-infected mice and humans. Utilizing this model, we immunized mice with alphavirus vectors (Venezuelan equine encephalitis [VEE] virus replicon particles [VRPs]) expressing Norwalk virus (NV) or Farmington Hills virus (FH) virus-like particles to evaluate T cell epitopes shared between human norovirus strains. Stimulation of splenocytes from norovirus VRP-immunized mice with overlapping peptides from complete libraries of the NV or FH capsid proteins revealed specific amino acid sequences containing T cell epitopes that were conserved within genoclusters and genogroups. Immunization with heterologous norovirus VRPs resulted in specific cross-reactive IFN-γ secretion profiles following stimulation with NV and FH peptides in the mouse. Identification of unique strain-specific and cross-reactive epitopes may provide insight into homologous and heterologous T cell-mediated norovirus immunity and provide a platform for the study of norovirus-induced cellular immunity in humans.
Enhanced capacity & coverage by Wi-Fi LTE Integration
Creators: name: Ling, Jonathan
name: Kanugovi, Satish
name: Vasudevan, Subramanian
name: Pramod, A Krishna
Publisher: name: arXiv
Year: 2014
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: Wi-Fi provides cost-effective data capacity at hotspots in conjunction with broadband cellular networks. The hotspots are required to capture a large number of users and provide high data rates. Data rates, over the Wi-Fi interface, are influenced by the media access protocol, which loses throughput due to delays and unintended collisions when a large number of users are active. The hotspot range which determines the number of users, that can associate, is limited by the lower power of the client rather than the access point. By diverting the traffic destined to the access point via another access network, both range and efficiency can be improved. This uplink redirection or diversion is achieved by simultaneous use of the Wi-Fi and LTE radio interfaces. Three options - loose, tight, and hybrid integration are presented towards providing enhanced capacity and coverage.
description: Submitted as a candidate article for IEEE Communications Magazine, Topic: The Future of Wi-Fi (November 2014)
A New Proof of Stirling's Formula
Creators: name: Neuschel, Thorsten
Publisher: name: arXiv
Year: 2014
Subjects: subject: History and Overview (math.HO)
subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics

description: A new simple proof of Stirling's formula via the partial fraction expansion for the tangent function is presented.
Metagenomic Analysis of the Viromes of Three North American Bat Species: Viral Diversity among Different Bat Species That Share a Common Habitat
Creators: name: Gates, J. E.
name: Huynh, J.
name: Moore, C. J.
name: Haskew, A. N.
name: Donaldson, E. F.
name: Frieman, M. B.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Effective prediction of future viral zoonoses requires an in-depth understanding of the heterologous viral population in key animal species that will likely serve as reservoir hosts or intermediates during the next viral epidemic. The importance of bats as natural hosts for several important viral zoonoses, including Ebola, Marburg, Nipah, Hendra, and rabies viruses and severe acute respiratory syndrome-coronavirus (SARS-CoV), has been established; however, the large viral population diversity (virome) of bats has been partially determined for only a few of the ∼1,200 bat species. To assess the virome of North American bats, we collected fecal, oral, urine, and tissue samples from individual bats captured at an abandoned railroad tunnel in Maryland that is cohabitated by 7 to 10 different bat species. Here, we present preliminary characterization of the virome of three common North American bat species, including big brown bats (Eptesicus fuscus), tricolored bats (Perimyotis subflavus), and little brown myotis (Myotis lucifugus). In samples derived from these bats, we identified viral sequences that were similar to at least three novel group 1 CoVs, large numbers of insect and plant virus sequences, and nearly full-length genomic sequences of two novel bacteriophages. These observations suggest that bats encounter and disseminate a large assortment of viruses capable of infecting many different animals, insects, and plants in nature.