cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Expansion of hydrogen-poor knots in the born-again planetary nebulae A30 and A78
Creators: name: Fang, Xuan
name: Guerrero, Martin A.
name: Marquez-Lugo, Ramon A.
name: Toala, Jesus A.
name: Arthur, Sarah J.
name: Chu, You-Hua
name: Blair, William P.
name: Gruendl, Robert A.
name: Hamann, Wolf-Rainer
name: Oskinova, Lida M.
name: Todt, Helge
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We analyze the expansion of hydrogen-poor knots and filaments in the born-again planetary nebulae A30 and A78 based on Hubble Space Telescope (HST) images obtained almost 20 yr apart. The proper motion of these features generally increases with distance to the central star, but the fractional expansion decreases, i.e., the expansion is not homologous. As a result, there is not a unique expansion age, which is estimated to be 610-950 yr for A30 and 600-1140 yr for A78. The knots and filaments have experienced complex dynamical processes: the current fast stellar wind is mass loaded by the material ablated from the inner knots; the ablated material is then swept up until it shocks the inner edges of the outer, hydrogen-rich nebula. The angular expansion of the outer filaments shows a clear dependence on position angle, indicating that the interaction of the stellar wind with the innermost knots channels the wind along preferred directions. The apparent angular expansion of the innermost knots seems to be dominated by the rocket effect of evaporating gas and by the propagation of the ionization front inside them. Radiation-hydrodynamical simulations show that a single ejection of material followed by a rapid onset of the stellar wind and ionizing flux can reproduce the variety of clumps and filaments at different distances from the central star found in A30 and A78.
description: 12 pages, 7 figures. Accepted for publication in the ApJ
Separate Basic Region Motifs within the Adeno-Associated Virus Capsid Proteins Are Essential for Infectivity and Assembly
Creators: name: Grieger, J. C.
name: Samulski, R. J.
name: Snowdy, S.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: Adeno-associated virus (AAV) is gaining momentum as a gene therapy vector for human applications. However, there remain impediments to the development of this virus as a vector. One of these is the incomplete understanding of the biology of the virus, including nuclear targeting of the incoming virion during initial infection, as well as assembly of progeny virions from structural components in the nucleus. Toward this end, we have identified four basic regions (BR) on the AAV2 capsid that represent possible nuclear localization sequence (NLS) motifs. Mutagenesis of BR1 (120QAKKRVL126) and BR2 (140PGKKRPV146) had minor effects on viral infectivity (∼4- and ∼10-fold, respectively), whereas BR3 (166PARKRLN172) and BR4 (307RPKRLN312) were found to be essential for infectivity and virion assembly, respectively. Mutagenesis of BR3, which is located in Vp1 and Vp2 capsid proteins, does not interfere with viral production or trafficking of intact AAV capsids to the nuclear periphery but does inhibit transfer of encapsidated DNA into the nucleus. Substitution of the canine parvovirus NLS rescued the BR3 mutant to wild-type (wt) levels, supporting the role of an AAV NLS motif. In addition, rAAV2 containing a mutant form of BR3 in Vp1 and a wt BR3 in Vp2 was found to be infectious, suggesting that the function of BR3 is redundant between Vp1 and Vp2 and that Vp2 may play a role in infectivity. Mutagenesis of BR4 was found to inhibit virion assembly in the nucleus of transfected cells. This affect was not completely due to the inefficient nuclear import of capsid subunits based on Western blot analysis. In fact, aberrant capsid foci were observed in the cytoplasm of transfected cells, compared to the wild type, suggesting a defect in early viral assembly or trafficking. Using three-dimensional structural analysis, the lysine- and arginine-to-asparagine change disrupts hydrogen bonding between these basic residues and adjacent beta strand glutamine residues that may prevent assembly of intact virions. Taken together, these data support that the BR4 domain is essential for virion assembly. Each BR was also found to be conserved in serotypes 1 to 11, suggesting that these regions are significant and function similarly in each serotype. This study establishes the importance of two BR motifs on the AAV2 capsid that are essential for infectivity and virion assembly.
How to Investigate Additive-Related Effects from Microplastics
Creators: name: Potthoff, Annegret
name: Müller-Köhn, Axel
name: Jemec Kokalj, Anita
name: Kühnel, Dana
Publisher: name: Zenodo
Year: 2022
Subjects: microplastics
nanoplastics
additives
ecotoxicology
toxicology
polymer particles
sample preparation

description: When assessing potentially harmful ecotoxicological or toxicological effects of microplastics, researchers are in a quandary: - To suit the requirements of interpretable experimental data, they aspire to have well-characterised, small particles, ideally with a narrow particle size distribution and ideally doped with a well detectable element like Europium. The desired polymer particles should not contain any other substances. - To obtain results that represent real exposure scenarios, the characteristics of the test material are completely different: Microplastics found in the environment differ in size and shape - and they do not only contain the polymer itself, but an unknown quantity of unidentified chemicals. An approach that combines both well-known characteristics and environmentally relevant properties should be developed. The sample preparation procedure should work not only for a variety of polymers and chemicals, but also for different organisms.
Bismuth ferrite as low-loss switchable material for plasmonic waveguide modulator
Creators: name: Babicheva, Viktoriia E.
name: Zhukovsky, Sergei V.
name: Lavrinenko, Andrei V.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We propose new designs of plasmonic modulators, which can be utilized for dynamic signal switching in photonic integrated circuits. We study performance of plasmonic waveguide modulator with bismuth ferrite as an active material. The bismuth ferrite core is sandwiched between metal plates (metal-insulator-metal configuration), which also serve as electrodes so that the core changes its refractive index under applied voltage by means of partial in-plane to out-of-plane reorientation of ferroelectric domains in bismuth ferrite. This domain switch results in changing of propagation constant and absorption coefficient, and thus either phase or amplitude control can be implemented. Efficient modulation performance is achieved because of high field confinement between the metal layers, as well as the existence of mode cut-offs for particular values of the core thickness, making it possible to control the signal with superior modulation depth. For the phase control scheme, π phase shift is provided by 0.8-μm length device having propagation losses 0.29 dB/μm. For the amplitude control, we predict up to 38 dB/μm extinction ratio with 1.2 dB/μm propagation loss. In contrast to previously proposed active materials, bismuth ferrite has nearly zero material losses, so bismuth ferrite based modulators do not bring about additional decay of the propagating signal.
Transcriptional Regulation of the Kaposi's Sarcoma-Associated Herpesvirus K15 Gene
Creators: name: Wong, E. L.
name: Damania, B.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: The K15 gene product of Kaposi's sarcoma-associated herpesvirus (KSHV) is a transmembrane protein that is encoded by the last open reading frame of the KSHV genome. The K15 protein has been implicated in modulation of B-cell signal transduction and activation of the Ras/mitogen-activated protein kinase and NF-κB signal transduction pathways. Here we report the identification of the transcriptional start site of the full-length K15 gene in KSHV-positive BCBL-1 cells. We have mapped the K15 transcriptional start site to a position 152 nucleotides upstream from the translation start site by rapid amplification of cDNA ends and RNase protection assays. We have also characterized the K15 promoter element. To analyze the cis-acting elements necessary to regulate K15 gene expression, a series of 5′ promoter deletion constructs were generated and subcloned upstream of the luciferase reporter gene. Transcriptional assays with these mutant promoters demonstrated that chemical induction in latently infected KSHV-positive BCBL-1 cells activated K15 transcription. In addition, K15 promoter transactivation was also mediated by the viral immediate-early protein Orf50/Rta, suggesting that the K15 gene is actively transcribed during lytic replication.
On the binary helium star DY Centauri: Chemical composition and evolutionary state
Creators: name: Pandey, Gajendra
name: Rao, N. Kameswara
name: Jeffery, C. Simon
name: Lambert, David L.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: DY Cen has shown a steady fading of its visual light by about 1 magnitude in the last 40 years suggesting a secular increase in its effective temperature. We have conducted non-LTE and LTE abundance analyses to determine the star's effective temperature, surface gravity, and chemical composition using high-resolution spectra obtained over two decades. The derived stellar parameters for three epochs suggest that DY Cen has evolved at a constant luminosity and has become hotter by about 5000 K in 23 years. We show that the derived abundances remain unchanged for the three epochs. The derived abundances of the key elements, including F and Ne, are as observed for the extreme helium stars resulting from a merger of an He white dwarf with a C-O white dwarf. Thus, DY Cen by chemical composition appears to be also a product of a merger of two white dwarfs. This appearance seems to be at odds with the recent suggestion that DY Cen is a single-lined spectroscopic binary.
description: Accepted to ApJ with 8 Figures and 5 Tables
Air-and water-stable halide perovskite nanocrystals protected with nearly-monolayer carbon nitride for CO2 photoreduction and water splitting
Creators: Laishram, Devika
Publisher: name: University of Alberta Library
Year: 2022

Halide perovskites are exciting candidates for broad-spectrum photocatalysts but have the problem of ambient stability. Protective shells of oxides and polymers around halide perovskite nano- and micro-crystals provide a measure of chemical and photochemical resilience but the photocatalytic performance of perovskites is compromised due to low electron mobility in amorphous oxide or polymer shells and rapid charge carrier recombination on the surface. Herein an in situ surface passivation and stabilization of CsPbBr3 nanocrystals was achieved using monolayered graphenic carbon nitride (CNM). Extensive characterization of carbon nitride protected CsPbBr3 nanocrystals (CNMBr) indicated spherical CsPbBr3 nanoparticles encased in a few nm thick g-C3N4 sheets facilitating better charge separation via percolation/tunneling of charges on conductive 2D nanosheets. The CNMBr core-shell nanocrystals demonstrated enhanced photoelectrochemical water splitting performance and photocurrent reaching up to 1.55 mA cm−2. The CNMBr catalyst was successfully deployed for CO2 photoreduction giving carbon monoxide and methane as the reaction products.
SDO/AIA Observations of a Reflecting Longitudinal Wave in a Coronal Loop
Creators: name: Kumar, Pankaj
name: Innes, D. E.
name: Inhester, B.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We report high resolution observations from the SDO/AIA of intensity oscillations in a hot, T~8-10 MK, loop. The AIA images show a large coronal loop that was rapidly heated following plasma ejection from one of the loop's footpoints. A wave-like intensity enhancement, seen very clearly in the 131 and 94 Å channel images, propagated ahead of the ejecta along the loop, and was reflected at the opposite footpoint. The wave reflected four times before fading. It was only seen in the hot, 131 and 94 Å channels. The characteristic period and the decay time of the oscillation was $\sim$630 and $\sim$440 s, respectively. The phase speed was about 460-510 km/s which roughly matches the sound speed of the loop (430-480 km/s). The observed properties of the oscillation are consistent with the observations of Doppler shift oscillations discovered by the SOHO/SUMER and with their interpretation as slow magnetoacoustic waves. We suggest that the impulsive injection of plasma, following reconnection at one of the loop footpoints, led to rapid heating and the propagation of a longitudinal compressive wave along the loop. The wave bounces back and forth a couple of times before fading.
description: 8 pages, 5 figures
Adeno-Associated Virus Type 2 (AAV2) Capsid-Specific Cytotoxic T Lymphocytes Eliminate Only Vector-Transduced Cells Coexpressing the AAV2 Capsid In Vivo
Creators: name: Ma, H.
name: Samulski, R. J.
name: Hirsch, M.
name: Asokan, A.
name: Zeithaml, B.
name: Li, C.
name: Kafri, T.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: A recent clinical trial has suggested that recombinant adeno-associated virus (rAAV) vector transduction in humans induces a cytotoxic T-lymphocyte (CTL) response against the AAV2 capsid. To directly address the ability of AAV capsid-specific CTLs to eliminate rAAV-transduced cells in vitro and in vivo in mice, we first demonstrated that AAV2 capsid-specific CTLs could be induced by dendritic cells with endogenous AAV2 capsid expression or pulsed with AAV2 vectors. These CTLs were able to kill a cell line stable for capsid expression in vitro and also in a mouse tumor xenograft model in vivo. Parent colon carcinoma (CT26) cells transduced with a large amount of AAV2 vectors in vitro were also destroyed by these CTLs. To determine the effect of CTLs on the elimination of target cells transduced by AAV2 vectors in vivo, we carried out adoptive transfer experiments. CTLs eliminated liver cells with endogenous AAV2 capsid expression but not liver cells transduced by AAV2 vectors, regardless of the reporter genes. Similar results were obtained for rAAV2 transduction in muscle. Our data strongly suggest that AAV vector-transduced cells are rarely eliminated by AAV2 capsid-specific CTLs in vivo, even though the AAV capsid can induce a CTL response. In conclusion, AAV capsid-specific CTLs do not appear to play a role in elimination of rAAV-transduced cells in a mouse model. In addition, our data suggest that the mouse model may not mimic the immune response noted in humans and additional modification to AAV vectors may be required for further study in order to elicit a similar cellular immune response.
Controlling interactions between highly-magnetic atoms with Feshbach resonances
Creators: name: Kotochigova, Svetlana
Publisher: name: arXiv
Year: 2014
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: This paper reviews current experimental and theoretical progress in the study of dipolar quantum gases of ground and meta-stable atoms with a large magnetic moment. We emphasize the anisotropic nature of Feshbach resonances due to coupling to fast-rotating resonant molecular states in ultracold s-wave collisions between magnetic atoms in external magnetic fields. The dramatic differences in the distribution of resonances of magnetic $^7$S$_3$ chromium and magnetic lanthanide atoms with a submerged 4f shell and non-zero electron angular momentum is analyzed. We focus on Dysprosium and Erbium as important experimental advances have been recently made to cool and create quantum-degenerate gases for these atoms. Finally, we describe progress in locating resonances in collisions of meta-stable magnetic atoms in electronic P states with ground-state atoms, where an interplay between collisional anisotropies and spin-orbit coupling exists.
Analysis of Murine Hepatitis Virus Strain A59 Temperature-Sensitive Mutant TS-LA6 Suggests that nsp10 Plays a Critical Role in Polyprotein Processing
Creators: name: Graham, R. L.
name: Baric, R. S.
name: Donaldson, E. F.
name: Sims, A. C.
name: Denison, M. R.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Coronaviruses are the largest RNA viruses, and their genomes encode replication machinery capable of efficient replication of both positive- and negative-strand viral RNAs as well as enzymes capable of processing large viral polyproteins into putative replication intermediates and mature proteins. A model described recently by Sawicki et al. (S. G. Sawicki, D. L. Sawicki, D. Younker, Y. Meyer, V. Thiel, H. Stokes, and S. G. Siddell, PLoS Pathog. 1:e39, 2005), based upon complementation studies of known temperature-sensitive (TS) mutants of murine hepatitis virus (MHV) strain A59, proposes that an intermediate comprised of nsp4 to nsp10/11 (∼150 kDa) is involved in negative-strand synthesis. Furthermore, the mature forms of nsp4 to nsp10 are thought to serve as cofactors with other replicase proteins to assemble a larger replication complex specifically formed to transcribe positive-strand RNAs. In this study, we introduced a single-amino-acid change (nsp10:Q65E) associated with the TS-LA6 phenotype into nsp10 of the infectious clone of MHV. Growth kinetic studies demonstrated that this mutation was sufficient to generate the TS phenotype at permissive and nonpermissive temperatures. Our results demonstrate that the TS mutant variant of nsp10 inhibits the main protease, 3CLpro, blocking its function completely at the nonpermissive temperature. These results implicate nsp10 as being a critical factor in the activation of 3CLpro function. We discuss how these findings challenge the current hypothesis that nsp4 to nsp10/11 functions as a single cistron in negative-strand RNA synthesis and analyze recent complementation data in light of these new findings.
c-Myc and Sp1 Contribute to Proviral Latency by Recruiting Histone Deacetylase 1 to the Human Immunodeficiency Virus Type 1 Promoter
Creators: name: Margolis, D. M.
name: Hazuda, D. J.
name: Espeseth, A.
name: Jiang, G.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Histone deacetylase (HDAC) inhibitors such as valproic acid (VPA) induce the expression of quiescent proviral human immunodeficiency virus type 1 (HIV-1) and may deplete proviral infection in vivo. To uncover novel molecular mechanisms that maintain HIV latency, we sought cellular mRNAs whose expression was diminished in resting CD4+ T cells of HIV-1-infected patients exposed to VPA. c-Myc was prominent among genes markedly downregulated upon exposure to VPA. c-Myc expression repressed HIV-1 expression in chronically infected cell lines. Chromatin immunoprecipitation (ChIP) assays revealed that c-Myc and HDAC1 are coordinately resident at the HIV-1 long terminal repeat (LTR) promoter and absent from the promoter after VPA treatment in concert with histone acetylation, RNA polymerase II recruitment, and LTR expression. Sequential ChIP assays demonstrated that c-Myc, Sp1, and HDAC1 coexist in the same DNA-protein complex at the HIV promoter. Short hairpin RNA inhibition of c-Myc reduces both c-Myc and HDAC1 occupancy, blocks c-Myc repression of Tat activation, and increases LTR expression. These results expand the understanding of mechanisms that recruit HDAC and maintain the latency of HIV-1, suggesting novel therapeutic approaches against latent proviral HIV infection.
Quantum correlations and distinguishability of quantum states
Creators: name: Spehner, Dominique
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: A survey of various concepts in quantum information is given, with a main emphasis on the distinguishability of quantum states and quantum correlations. Covered topics include generalized and least square measurements, state discrimination, quantum relative entropies, the Bures distance on the set of quantum states, the quantum Fisher information, the quantum Chernoff bound, bipartite entanglement, the quantum discord, and geometrical measures of quantum correlations. The article is intended both for physicists interested not only by collections of results but also by the mathematical methods justifying them, and for mathematicians looking for an up-to-date introductory course on these subjects, which are mainly developed in the physics literature.
description: Review article, 103 pages, to appear in J. Math. Phys. 55 (special issue: non-equilibrium statistical mechanics, 2014)
Complement Contributes to Inflammatory Tissue Destruction in a Mouse Model of Ross River Virus-Induced Disease
Creators: name: Heise, M. T.
name: Fraser, R. J.
name: Morrison, T. E.
name: Mahalingam, S.
name: Smith, P. N.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Arthritogenic alphaviruses, including Ross River virus (RRV) and chikungunya virus, are mosquito-borne viruses that cause significant human disease worldwide, including explosive epidemics that can result in thousands to millions of infected individuals. Similar to infection of humans, infection of C57BL/6 mice with RRV results in severe monocytic inflammation of bone, joint, and skeletal muscle tissues. We demonstrate here that the complement system, an important component of the innate immune response, enhances the severity of RRV-induced disease in mice. Complement activation products were detected in the inflamed tissues and in the serum of RRV-infected wild-type mice. Furthermore, mice deficient in C3 (C3−/−), the central component of the complement system, developed much less severe disease signs than did wild-type mice. Complement-mediated chemotaxis is essential for many inflammatory arthritides; however, RRV-infected wild-type and C3−/− mice had similar numbers and composition of inflammatory infiltrates within hind limb skeletal muscle tissue. Despite similar inflammatory infiltrates, RRV-infected C3−/− mice exhibited far less severe destruction of skeletal muscle tissue. In addition to these studies, complement activation was also detected in synovial fluid from RRV-infected patients. Taken together, these findings indicate that complement activation occurs in the tissues of humans and mice infected with RRV and suggest that complement plays an essential role in the effector phase, but not the inductive phase, of RRV-induced arthritis and myositis.
Differential Induction of Type I Interferon Responses in Myeloid Dendritic Cells by Mosquito and Mammalian-Cell-Derived Alphaviruses
Creators: name: Morrison, T. E.
name: Mahalingam, S.
name: Hueston, L.
name: Moore, C.
name: Rulli, N.
name: Suthar, M. S.
name: Lidbury, B.
name: Shabman, R. S.
name: Heise, M. T.
name: White, L.
name: Ting, J. P.-Y.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Dendritic cells (DCs) are an important early target cell for many mosquito-borne viruses, and in many cases mosquito-cell-derived arboviruses more efficiently infect DCs than viruses derived from mammalian cells. However, whether mosquito-cell-derived viruses differ from mammalian-cell-derived viruses in their ability to induce antiviral responses in the infected dendritic cell has not been evaluated. In this report, alphaviruses, which are mosquito-borne viruses that cause diseases ranging from encephalitis to arthritis, were used to determine whether viruses grown in mosquito cells differed from mammalian-cell-derived viruses in their ability to induce type I interferon (IFN) responses in infected primary dendritic cells. Consistent with previous results, mosquito-cell-derived Ross River virus (mos-RRV) and Venezuelan equine encephalitis virus (mos-VEE) exhibited enhanced infection of primary myeloid dendritic cells (mDCs) compared to mammalian-cell-derived virus preparations. However, unlike the mammalian-cell-derived viruses, which induced high levels of type I IFN in the infected mDC cultures, mos-RRV and mos-VEE were poor IFN inducers. Furthermore, the poor IFN induction by mos-RRV contributed to the enhanced infection of mDCs by mos-RRV. These results suggest that the viruses initially delivered by the mosquito vector differ from those generated in subsequent rounds of replication in the host, not just with respect to their ability to infect dendritic cells but also in their ability to induce or inhibit antiviral type I IFN responses. This difference may have an important impact on the mosquito-borne virus's ability to successfully make the transition from the arthropod vector to the vertebrate host.
Epstein-Barr Virus-Encoded Protein Kinase (BGLF4) Is Involved in Production of Infectious Virus
Creators: name: Gershburg, E.
name: Pagano, J. S.
name: Torrisi, M. R.
name: Raffa, S.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: The Epstein-Barr virus (EBV) BGLF4 gene product is a protein kinase (PK). Although this kinase has been characterized and several of its targets have been identified, its biological role remains enigmatic. We have generated and assessed a BGLF4 knockdown phenotype by means of RNA interference and report the following: (i) BGLF4-targeting small interfering RNA effectively inhibited the expression of its product, the viral PK, during lytic reactivation, (ii) BGLF4 knockdown partially inhibited viral DNA replication and expression of selected late viral genes, (iii) the absence of EBV PK resulted in retention of the viral nucleocapsids in the nuclei, and (iv) as a result of the nuclear retention, release of infectious virions is significantly retarded. Our results provide evidence that EBV PK plays an important role in nuclear egress of the virus and ultimately is crucial for lytic virus replication.
Functional p53 Signaling in Kaposi's Sarcoma-Associated Herpesvirus Lymphomas: Implications for Therapy
Creators: name: Petre, C. E.
name: Dittmer, D. P.
name: Sin, S.-H.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: The Kaposi's sarcoma-associated herpesvirus (KSHV/HHV8) is associated with Kaposi's sarcoma (KS) as well as primary effusion lymphomas (PEL). The expression of viral proteins capable of inactivating the p53 tumor suppressor protein has been implicated in KSHV oncogenesis. However, DNA-damaging drugs such as doxorubicin are clinically efficacious against PEL and KS, suggesting that p53 signaling remains intact despite the presence of KSHV. To investigate the functionality of p53 in PEL, we examined the response of a large number of PEL cell lines to doxorubicin. Two out of seven (29%) PEL cell lines harbored a mutant p53 allele (BCBL-1 and BCP-1) which led to doxorubicin resistance. In contrast, all other PEL containing wild-type p53 showed DNA damage-induced cell cycle arrest, p53 phosphorylation, and p53 target gene activation. These data imply that p53-mediated DNA damage signaling was intact. Supporting this finding, chemical inhibition of p53 signaling in PEL led to doxorubicin resistance, and chemical activation of p53 by the Hdm2 antagonist Nutlin-3 led to unimpaired induction of p53 target genes as well as growth inhibition and apoptosis.
comparison-between-agonist-trigger-with-hcg-luteal-phase-supplementation-vs-hcg-trigger-with-progesterone-luteal-phase-s.pdf
Creators: name: Nawara, Maii
Publisher: name: figshare
Year: 2022
Subjects: subject: 111402 Obstetrics and Gynaecology
subject: FOS: Clinical medicine

description: Infertility
Quantifying the Heating Sources for Mid-infrared Dust Emissions in Galaxies: The Case of M 81
Creators: name: Lu, Nanyao
name: Bendo, G. J.
name: Boselli, A.
name: Baes, M.
name: Wu., H.
name: Madden, S. C.
name: De Looze, I.
name: Rémy-Ruyer, A.
name: Boquien, M.
name: Wilson, C. D.
name: Galametz, M.
name: Lam, M. I.
name: Cooray, A.
name: Spinoglio, L.
name: Zhao, Y.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: With the newly available SPIRE images at 250 and 500 micron from Herschel Space Observatory, we study quantitative correlations over a sub-kpc scale among three distinct emission components in the interstellar medium of the nearby spiral galaxy M 81 (NGC 3031): (a) $I_{8}$ or $I_{24}$, the surface brightness of the mid-infrared emission observed in the Spitzer IRAC 8 or MIPS 24 micron band, with $I_8$ and $I_{24}$ being dominated by the emissions from Polycyclic Aromatic Hydrocarbons (PAHs) and very small grains (VSGs) of dust, respectively; (b) $I_{500}$, that of the cold dust continuum emission in the Herschel SPIRE 500 micron band, dominated by the emission from large dust grains heated by evolved stars, and (c) $I_{{\rm H}α}$, a nominal surface brightness of the H$α$ line emission, from gas ionized by newly formed massive stars. The results from our correlation study, free from any assumption on or modeling of dust emissivity law or dust temperatures, present solid evidence for significant heating of PAHs and VSGs by evolved stars. In the case of M 81, about 67% (48%) of the 8 micron (24 micron) emission derives its heating from evolved stars, with the remainder attributed to radiation heating associated with ionizing stars.
description: 11 pages, 7 figures; accepted for publication in the Astrophysical Journal
Role of ZnO in ZnO Nanoflake/Ti3C2 MXene Composites in Photocatalytic and Electrocatalytic Hydrogen Evolution
Creators: Laishram, Devika
Publisher: name: University of Alberta Library
Year: 2022

Herein, we report a simple hydrothermal synthesis of ZnO-Ti3C2 MXene nanocomposites with a varying wt % of ZnO to exploit the synergistic effect of 2D layer structured Ti3C2 and semiconductor ZnO for photocatalysis and electrocatalysis applications. A systematic study on the efficiency of ZnO-Ti3C2 nanocomposites toward the degradation of organic pollutants (dyes and pharmaceuticals) and the hydrogen evolution reaction (HER) is demonstrated. Among the developed nanohybrid catalysts, the ZnO-Ti3C2 composite with 10 wt % ZnO (MXZnO-10) showed the highest photodegradation efficiency of 76.4% within 10 min of the reaction and 99.2% in 60 min for methylene blue (MB) dye. The synergistic interactions between 2D layered Ti3C2 and ZnO improved the lifetime of electrons and holes by reducing the recombination rate. The uncombined electrons and holes facilitated the effective degradation of the MB dye. The ZnO-Ti3C2 nanocomposite with 5 wt % ZnO (MXZnO-5) showed excellent HER performance and exhibited an overpotential of 495 mV at 10 mA/cm2 with a Tafel slope of 108 mV/dec. This work widens the application range of transition metal oxide–MXene composites, providing potential substitute materials for photocatalysis and electrocatalysis applications.
Record statistics of financial time series and geometric random walks
Creators: name: Sabir, Behlool
name: Santhanam, M. S.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Statistical Finance (q-fin.ST)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Economics and business
subject: FOS: Physical sciences

description: The study of record statistics of correlated series is gaining momentum. In this work, we study the records statistics of the time series of select stock market data and the geometric random walk, primarily through simulations. We show that the distribution of the age of records is a power law with the exponent $α$ lying in the range $1.5 \le α\le 1.8$. Further, the longest record ages follow the Fréchet distribution of extreme value theory. The records statistics of geometric random walk series is in good agreement with that from the empirical stock data.
description: 4 pages, 5 figures
Heparan Sulfate Binding Can Contribute to the Neurovirulence of Neuroadapted and Nonneuroadapted Sindbis Viruses
Creators: name: Thompson, J. M.
name: Ryman, K. D.
name: Gardner, C. L.
name: Burke, C. W.
name: Klimstra, W. B.
name: Meier, K. C.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Cell culture-adapted laboratory strains of Sindbis virus (SB) exhibit efficient initial attachment to cell surface heparan sulfate (HS) receptors. In contrast, non-cell-adapted strains, such as the SB consensus sequence virus TR339, interact weakly with HS and cell surfaces. Regardless of their HS binding phenotype, most SB strains do not cause fatal disease in adult mice, whether inoculated subcutaneously (s.c.) or intracranially (i.c.). However, laboratory strains of SB can be rendered neurovirulent for adult mice by introduction of a glutamine (Gln)-to-histidine (His) mutation at position 55 of the E2 envelope glycoprotein. In the current work, we have determined that E2 His 55-containing viruses require a second-site mutation (Glu to Lys) at E2 position 70 that confers efficient HS binding in order to exhibit virulence for adult mice and that virulence is correlated with very high infectivity for many cell types. Furthermore, introduction of E2 Lys 70 or certain other HS-binding mutations alone also increased morbidity and/or mortality over that of TR339 for older mice inoculated i.c. However, all viruses containing single HS-binding mutations were attenuated in s.c. inoculated suckling mice in comparison with TR339. These results suggest that HS binding may attenuate viral disease that is dependent on high-titer viremia; however, efficient cell attachment through HS binding can increase virulence, presumably through enhancing the replication of SB within specific host tissues such as the brain.
Increased Immunogenicity of a DNA-Launched Venezuelan Equine Encephalitis Virus-Based Replicon DNA Vaccine
Creators: name: Shabman, R. S.
name: Montefiori, D. C.
name: Collier, M. L.
name: Moran, T. P.
name: Beard, C.
name: Kraus, A. A.
name: Fluet, M. E.
name: Whitmore, A. C.
name: Ljungberg, K.
name: Thompson, J. M.
name: Johnston, R. E.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: A novel genetic vaccine that is based on a Venezuelan equine encephalitis virus (VEE) replicon launched from plasmid DNA is described. The plasmid encodes a VEE replicon under the transcriptional control of the cytomegalovirus immediate-early promoter (VEE DNA). The VEE DNA consistently expressed 3- to 15-fold more green fluorescent protein in vitro than did a conventional DNA vaccine. Furthermore, transfection with the DNA-launched VEE replicon induced apoptosis and type I interferon production. Inoculation of mice with VEE DNA encoding human immunodeficiency virus type 1 gp160 significantly increased humoral responses by several orders of magnitude compared to an equal dose of a conventional DNA vaccine. These increases were also observed at 10- and 100-fold-lower doses of the VEE DNA. Cellular immune responses measured by gamma interferon and interleukin 2 enzyme-linked immunospot assay were significantly higher in mice immunized with the VEE DNA at decreased doses. The immune responses induced by the VEE DNA-encoded antigen, however, were independent of an intact type I interferon signaling pathway. Moreover, the DNA-launched VEE replicon induced an efficient prime to a VEE replicon particle (VRP) boost, increasing humoral and cellular immunity by at least 1 order of magnitude compared to VEE DNA only. Importantly, immunization with VEE DNA, as opposed to VRP, did not induce any anti-VRP neutralizing antibodies. Increased potency of DNA vaccines and reduced vector immunity may ultimately have an impact on the design of vaccination strategies in humans.
Independent Evolution of Human Immunodeficiency Virus Type 1 env V1/V2 and V4/V5 Hypervariable Regions during Chronic Infection
Creators: name: Kitrinos, K. M.
name: Swanstrom, R.
name: Harrington, P. R.
name: Nelson, J. A. E.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Using DNA heteroduplex tracking assays, we characterized human immunodeficiency virus type 1 env V4/V5 genetic populations in multiple blood plasma samples collected over an average of 7 months from 24 chronically infected human subjects. We observed complex and dynamic V4/V5 genetic populations in most subjects. Comparisons of V4/V5 and V1/V2 population changes over the course of the study showed that major shifts in genetic populations frequently occurred in one region but not the other, and these observations were independently confirmed in one subject by single-genome sequencing. These results suggest that the V1/V2 and V4/V5 regions of env often evolve independently during chronic infection.
Induction of Epidermal Growth Factor Receptor Expression by Epstein-Barr Virus Latent Membrane Protein 1 C-Terminal-Activating Region 1 Is Mediated by NF- B p50 Homodimer/Bcl-3 Complexes
Creators: name: Thornburg, N. J.
name: Raab-Traub, N.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: The Epstein-Barr virus (EBV) is associated with the development of numerous malignancies, including the epithelial malignancy nasopharyngeal carcinoma (NPC). The viral oncoprotein latent membrane protein 1 (LMP1) is expressed in almost all EBV-associated malignancies and has profound effects on gene expression. LMP1 acts as a constitutively active tumor necrosis factor receptor and activates multiple forms of the NF-κB family of transcription factors. LMP1 has two domains that both activate NF-κB. In epithelial cells, LMP1 C-terminal activating region 1 (CTAR1) uniquely activates p50/p50-, p50/p52-, and p65-containing complexes while CTAR2 activates canonical p50/p65 complexes. CTAR1 also uniquely upregulates the epidermal growth factor receptor (EGFR). In NPC, NF-κB p50/p50 homodimers and the transactivator Bcl-3 were detected on the EGFR promoter. In this study, the role of NF-κB p50 and Bcl-3 in LMP1-mediated upregulation of EGFR was analyzed. In LMP1-CTAR1-expressing cells, chromatin immunoprecipitation detected p50 and Bcl-3 on the NF-κB consensus sites within the egfr promoter. Transient overexpression of p50 and Bcl-3 increased EGFR expression, confirming the regulation of EGFR by these factors. Treatment with p105/p50 siRNA effectively reduced p105/p50 levels but unexpectedly increased Bcl-3 expression and levels of p50/Bcl-3 complexes, resulting in increased EGFR expression. These data suggest that induction of p50/p50/Bcl-3 complexes by LMP1 CTAR1 mediates LMP1-induced EGFR upregulation and that formation of the p50/p50/Bcl-3 complex is negatively regulated by the p105 precursor. The distinct forms of NF-κB that are induced by LMP1 CTAR1 likely activate distinct cellular genes.
Rapid Detection and Quantification of Micro-plastic Particles using MuScan® Technology
Creators: name: van Doorn, Ronald
name: Ash, Edward
name: Klerks, Michel
Publisher: name: Zenodo
Year: 2022
Subjects: microplastics
spectroscopy
Raman spectrometry
chromatography
plastic particles
nanoplastics

description: Here we propose a simple, fast on-site MuScan® method that automatically analyses the number of micro-plastic particles in a sample. The Muscan® method reliably detects and quantifies micro-plastics, even down to 1 µm in size. Current simple methods often rely on manually viewing and counting micro-plastics in a sample under a microscope. More
 advanced techniques use Fourier-transform infrared spectroscopy (FT-IR), Raman spectrometry, and chromatography/mass spectrometry (GC/MS, ICP-MS). However, with these methods a reliable, objective quantification and determination of the size of micro-plastics in larger sample volumes is not possible or can be very cumbersome. As these advanced methods require large financial investments, need a high degree of expertise and are not easy to perform on-site, there is an urgent need for a more rapid, simple and cost-effective method.
Molecular Characterization of the Rhesus Rhadinovirus (RRV) ORF4 Gene and the RRV Complement Control Protein It Encodes
Creators: name: Spiller, O. B.
name: Okroj, M.
name: Blom, A. M.
name: Chanas, S.
name: Wong, S. W.
name: Mark, L.
name: Aitken, J. A.
name: Damania, B.
name: Blackbourn, D. J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: The diversity of viral strategies to modulate complement activation indicates that this component of the immune system has significant antiviral potential. One example is the Kaposi's sarcoma-associated herpesvirus (KSHV) complement control protein (KCP), which inhibits progression of the complement cascade. Rhesus rhadinovirus (RRV), like KSHV, is a member of the subfamily Gammaherpesvirinae and currently provides the only in vivo model of KSHV pathobiology in primates. In the present study, we characterized the KCP homologue encoded by RRV, RRV complement control protein (RCP). Two strains of RRV have been sequenced to date (H26-95 and 17577), and the RCPs they encode differ substantially in structure: RCP from strain H26-95 has four complement control protein (CCP) domains, whereas RCP from strain 17577 has eight CCP domains. Transcriptional analyses of the RCP gene (ORF4, referred to herein as RCP) in infected rhesus macaque fibroblasts mapped the ends of the transcripts of both strains. They revealed that H26-95 encodes a full-length, unspliced RCP transcript, while 17577 RCP generates a full-length unspliced mRNA and two alternatively spliced transcripts. Western blotting confirmed that infected cells express RCP, and immune electron microscopy disclosed this protein on the surface of RRV virions. Functional studies of RCP encoded by both RRV strains revealed their ability to suppress complement activation by the classical (antibody-mediated) pathway. These data provide the foundation for studies into the biological significance of gammaherpesvirus complement regulatory proteins in a tractable, non-human primate model.
MUC1 Induced by Epstein-Barr Virus Latent Membrane Protein 1 Causes Dissociation of the Cell-Matrix Interaction and Cellular Invasiveness via STAT Signaling
Creators: name: Pagano, J. S.
name: Yoshizaki, T.
name: Wakisaka, N.
name: Furukawa, M.
name: Murono, S.
name: Kondo, S.
name: Joab, I.
name: Jang, K. L.
name: Horikawa, T.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Disruption of cellular adhesion is an essential pathobiologic step leading to tumor dissemination. Mucin 1 (MUC1) is a mucinous glycoprotein expressed at the surfaces of epithelial cells in many tissues and their carcinomas. MUC1 plays crucial roles in tumor invasion and metastasis, especially in opposing cell adhesion. We have shown that virus infection, specifically by the human tumor virus Epstein-Barr virus (EBV) induces a spectrum of cellular invasiveness and metastasis factors. Here we show that expression of MUC1 is increased in diverse latently EBV-infected cell lines that express latent membrane protein 1 (LMP1), the main viral oncoprotein, and that the level of MUC1 was suppressed by expression of a dominant-negative mutant of LMP1. Expression of LMP1 in EBV-negative nasopharyngeal cell lines induces expression of MUC1 through activation of the MUC1 promoter via binding of STAT1 and STAT3. Finally, LMP1 reduces cell adhesion ability, which is restored by inhibition of MUC1 expression with MUC1 small interfering RNA (siRNA). In addition, LMP1 increases cell invasiveness, which is suppressed by MUC1 siRNA. Thus, LMP1 induces MUC1, a factor important in an early step of detachment and release of tumor cells, which along with induction of other invasiveness and angiogenic factors may combine to act in a complex sequential process that culminates in metastasis of EBV-infected tumor cells.
Role of relaxation time scale in noisy signal transduction
Creators: name: Maity, Alok Kumar
name: Chaudhury, Pinaki
name: Banik, Suman K.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Molecular Networks (q-bio.MN)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Intracellular fluctuations, mainly triggered by gene expression, are an inevitable phenomenon observed in living cells. It influences generation of phenotypic diversity in genetically identical cells. Such variation of cellular components is beneficial in some contexts but detrimental in others. To quantify the fluctuations in a gene product, we undertake an analytical scheme for studying few naturally abundant linear as well as branched chain network motifs. We solve the Langevin equations associated with each motif under the purview of linear noise approximation and quantify Fano factor and mutual information. Both quantifiable expressions exclusively depend on the relaxation time (decay rate constant) and steady state population of the network components. We investigate the effect of relaxation time constraints on Fano factor and mutual information to indentify a time scale domain where a network can recognize the fluctuations associated with the input signal more reliably. We also show how input population affects both quantities. We extend our calculation to long chain linear motif and show that with increasing chain length, the Fano factor value increases but the mutual information processing capability decreases. In this type of motif, the intermediate components are shown to act as a noise filter that tune up input fluctuations and maintain optimum fluctuations in the output. For branched chain motifs, both quantities vary within a large scale due to their network architecture and facilitate survival of living system in diverse environmental conditions.
description: 14 pages, 6 figures