cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Arsenic (+ 3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate Ciona intestinalis
Creators: name: The University of North Carolina at Chapel Hill University Libraries
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Metabolic conversion of inorganic arsenic into methylated products is a multistep process that yields mono-, di-, and trimethylated arsenicals. In recent years, it has become apparent that formation of methylated metabolites of inorganic arsenic is not necessarily a detoxification process. Intermediates and products formed in this pathway may be more reactive and toxic than inorganic arsenic. Like all metabolic pathways, understanding the pathway for arsenic methylation involves identification of each individual step in the process and the characterization of the molecules which participate in each step. Among several arsenic methyltransferases that have been identified, arsenic (+3 oxidation state) methyltransferase is the one best characterized at the genetic and functional levels. This review focuses on phylogenetic relationships in the deuterostomal lineage for this enzyme and on the relation between genotype for arsenic (+3 oxidation state) methyltransferase and phenotype for conversion of inorganic arsenic to methylated metabolites. Two conceptual models for function of arsenic (+3 oxidation state) methyltransferase which posit different roles for cellular reductants in the conversion of inorganic arsenic to methylated metabolites are compared. Although each model accurately represents some aspects of enzyme’s role in the pathway for arsenic methylation, neither model is a fully satisfactory representation of all the steps in this metabolic pathway. Additional information on the structure and function of the enzyme will be needed to develop a more comprehensive model for this pathway.
Transverse quantum decoherence of a fast particle in a gas
Creators: name: Gaspard, David
name: Sparenberg, Jean-Marc
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The decoherence of a fast quantum particle in a gas is studied by applying the Kramers-Moyal expansion to the quantum master equation for the reduced density matrix of the particle. This expansion leads to a general form of the Caldeira-Leggett master equation accounting for the angular variation of the differential cross section. The equation describes the decoherence in both the longitudinal and transverse directions with respect to the particle motion. It is shown that, when the differential cross section is concentrated in the forward direction, transverse decoherence dominates. The coherence region off the diagonal of the density matrix is characterized by coherence lengths, which can be deduced, for Gaussian states, from the momentum covariance matrix according to a Heisenberg-type uncertainty relation. Finally, the longitudinal-to-transverse ratio of the coherence lengths is estimated for an alpha particle of a few MeVs. This ratio indicates that the coherence region looks like an ellipsoid elongated in the direction of motion.
description: 18 pages, 3 figures, 76 references
Coupled minimal models revisited
Creators: name: Antunes, António
name: Behan, Connor
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study coupled unitary Virasoro minimal models in the large rank ($m \rightarrow \infty$) limit. In large $m$ perturbation theory, we find two non-trivial IR fixed points which exhibit irrational coefficients in several anomalous dimensions and the central charge. For $N>4$ copies, we show that the IR theory breaks all possible currents that would otherwise enhance the Virasoro algebra, up to spin 10. This provides strong evidence that the IR fixed points are examples of compact, unitary, irrational CFTs with the minimal amount of chiral symmetry. We also analyze anomalous dimension matrices for a family of degenerate operators with increasing spin. These display further evidence of irrationality and begin to reveal the form of the leading quantum Regge trajectory.
description: 4+2 pages, 2 figures, 1 table; v2: matches published version
Supernova 2013by: A Type IIL Supernova with a IIP-like light curve drop
Creators: name: Valenti, S.
name: Sand, D.
name: Stritzinger, M.
name: Howell, D. A.
name: Arcavi, I.
name: McCully, C.
name: Childress, M. J.
name: Hsiao, E. Y.
name: Contreras, C.
name: Morrell, N.
name: Phillips, M. M.
name: Gromadzki, M.
name: Kirshner, R. P.
name: Marion, G. H.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present multi-band ultraviolet and optical light curves, as well as visual-wavelength and near-infrared spectroscopy of the Type II linear (IIL) supernova (SN) 2013by. We show that SN 2013by and other SNe IIL in the literature, after their linear decline phase that start after maximum, have a sharp light curve decline similar to that seen in Type II plateau (IIP) supernovae. This light curve feature has rarely been observed in other SNe IIL due to their relative rarity and the intrinsic faintness of this particular phase of the light curve. We suggest that the presence of this drop could be used as a physical parameter to distinguish between subclasses of SNe II, rather than their light curve decline rate shortly after peak. Close inspection of the spectra of SN 2013by indicate asymmetric line profiles and signatures of high-velocity hydrogen. Late (less than 90 days after explosion) near-infrared spectra of SN 2013by exhibit oxygen lines, indicating significant mixing within the ejecta. From the late-time light curve, we estimate that 0.029 solar mass of 56Ni was synthesized during the explosion. It is also shown that the V -band light curve slope is responsible for part of the scatter in the luminosity (V magnitude 50 days after explosion) vs. 56Ni relation. Our observations of SN 2013by and other SNe IIL through the onset of the nebular phase indicate that their progenitors are similar to those of SNe IIP.
description: submitted 2014 December 5th, accepted 2015 January 28th
Decision of RMIT University against Professor Dr. Engr. Md. Anowar Hossain, School of Fashion & Textiles, RMIT University when Professor (Dr.) Rajiv Padhye did a conspiracy to kill Engr. Md. Anowar Hossain, PhD candidate, School of Fashion & Textiles, RMIT University supervised by Professor (Dr.) Lijing Wang and Emeritus Professor (Dr.) Robert Shanks, School of Fashion & Textiles, RMIT University; Engr. Md. Anowar Hossain faced hidden life threatening and notified to Professor (Dr.) Alec Cameron, Vice Chancellor, RMIT University
Creators: name: Hossain, Anowar
Publisher: name: Zenodo
Year: 2023
Subjects: RMIT University, Nobel Nominee, Professor Dr. Engr. Md. Anowar Hossain

description: Decision of RMIT University against Professor Dr. Engr. Md. Anowar Hossain, School of Fashion & Textiles, RMIT University when Professor (Dr.) Rajiv Padhye did a conspiracy to kill Engr. Md. Anowar Hossain, PhD candidate, School of Fashion & Textiles, RMIT University supervised by Professor (Dr.) Lijing Wang and Emeritus Professor (Dr.) Robert Shanks, School of Fashion & Textiles, RMIT University; Engr. Md. Anowar Hossain faced hidden life threatening and notified to Professor (Dr.) Alec Cameron, Vice Chancellor, RMIT University
Activated protein C promotes breast cancer cell migration through interactions with EPCR and PAR-1
Creators: name: Church, Frank C.
name: Beaulieu, Lea M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Activated protein C (APC) is a serine protease that regulates thrombin (IIa) production through inactivation of blood coagulation factors Va and VIIIa. APC also has non-hemostatic functions related to inflammation, proliferation, and apoptosis through various mechanisms. Using two breast cancer cell lines, MDA-MB-231 and MDA-MB-435, we investigated the role of APC in cell chemotaxis and invasion. Treatment of cells with increasing APC concentrations (1–50 μg/ml) increased invasion and chemotaxis in a concentration-dependent manner. Only the active form of APC increased invasion and chemotaxis of the MDA-MB-231 cells when compared to 3 inactive APC derivatives. Using a modified “checkerboard” analysis, APC was shown to only affect migration when plated with the cells; therefore, APC is not a chemoattractant. Blocking antibodies to endothelial protein C receptor (EPCR) and protease-activated receptor-1 (PAR-1) attenuated the effects of APC on chemotaxis in the MDA-MB-231 cells. Finally, treatment of the MDA-MB-231 cells with the proliferation inhibitor, Na butyrate, showed that APC did not increase migration by increasing cell number. Therefore, APC increases invasion and chemotaxis of cells by binding to the cell surface and activating specific signaling pathways through EPCR and PAR-1.
Global functional analysis of nucleophosmin in Taxol response, cancer, chromatin regulation, and ribosomal DNA transcription
Creators: name: Brickey, W. June
name: Ting, Jenny P.-Y.
name: Taxman, Debra J.
name: Bergstralh, Daniel T.
name: Conti, Brian J.
name: Moore, Chris B.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Analysis of lung cancer response to chemotherapeutic agents showed the accumulation of a Taxol-induced protein that reacted with an anti-phospho-MEK1/2 antibody. Mass spectroscopy identified the protein as nucleophosmin/B23 (NPM), a multifunctional protein with diverse roles: ribosome biosynthesis, p53 regulation, nuclear-cytoplasmic shuttling, and centrosome duplication. Our work demonstrates that following cellular exposure to mitosis-arresting agents NPM is phosphorylated and its chromatographic property is altered, suggesting changes in function during mitosis. To determine the functional relevance of NPM, its expression in tumor cells was reduced by siRNA. Cells with reduced NPM were treated with Taxol followed by microarray profiling accompanied by gene/protein pathway analyses. These studies demonstrate several expected and unexpected consequences of NPM depletion. The predominant downstream effectors of NPM are genes involved in cell proliferation, cancer, and the cell cycle. In congruence with its role in cancer, NPM is over-expressed in primary malignant lung cancer tissues. We also demonstrate a role for NPM in the expression of genes encoding SET (TAF1β) and the histone methylase SET8. Additionally, we show that NPM is required for a previously unobserved G2/M upregulation of TAF1A, which encodes the rDNA transcription factor TAFI48. These results demonstrate multi-faceted functions of NPM that can affect cancer cells.
Supplementary document for Multipass wide-field phase imaging - 6643681.pdf
Creators: name: Cuevas, Álvaro
name: Tiemann, Daniel
name: Camphausen, Robin
name: Cusini, Iris
name: Panzani, Antonio
name: Mukherjee, Rajdeep
name: Villa, Federica
name: Pruneri, Valerio
Publisher: name: Optica Publishing Group
Year: 2023
Subjects: Uncategorized

description: Side-by-side comparison of Supplemental information included
Palladin interacts with SH3 domains of SPIN90 and Src and is required for Src-induced cytoskeletal remodeling
Creators: name: Carpen, Olli
name: Song, Woo Keun
name: Taivainen, Anu
name: Ehler, Elisabeth
name: Rönty, Mikko
name: Otey, Carol
name: Heiska, Leena
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Palladin and SPIN90 are widely expressed proteins, which participate in modulation of actin cytoskeleton by binding to a variety of scaffold and signaling molecules. Cytoskeletal reorganization can induced by activation of signaling pathways, including the PDGF receptor and Src tyrosine kinase pathways. In this study we have analyzed the interplay between palladin, SPIN90 and Src, and characterized the role of palladin and SPIN90 in PDGF and Src-induced cytoskeletal remodeling. We show that the SH3 domains of SPIN90 and Src directly bind palladin’s poly-proline sequence and the interaction controls intracellular targeting of SPIN90. In PDGF-treated cells, palladin and SPIN90 co-localize in actin rich membrane ruffles and lamellipodia. The effect of PDGF on the cytoskeleton is at least partly mediated by the Src kinase, since PP2, a selective Src kinase family inhibitor, blocked PDGF-induced changes. Furthermore, expression of active Src kinase resulted in coordinated translocation of both palladin and SPIN90 to membrane protrusions. Knock-down of endogenous SPIN90 did not inhibit Src-induced cytoskeletal rearrangement, whereas knock-down of palladin resulted in cytoskeletal disorganization and inhibition of remodeling. Further studies showed that palladin is tyrosine phosphorylated in cells expressing active Src indicating bidirectional interplay between palladin and Src. These results may have implications in understanding the invasive and metastatic phenotype of neoplastic cells induced by Src.
Contrasting chemical pressure effect on the moment direction in the Kondo semiconductor CeT$_2$Al$_{10}$ (T = Ru,Os)
Creators: name: Adroja, D. T.
name: Hillier, A. D.
name: Ritter, C.
name: Bhattacharyya, A.
name: Khalyavin, D. D.
name: Strydom, A. M.
name: Peratheepan, P.
name: Fak, B.
name: Koza, M. M.
name: Kawabata, J.
name: Yamada, Y.
name: Okada, Y.
name: Muro, Y.
name: Takabatake, T.
name: Taylor, J. W.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The opening of a spin gap in the orthorhombic compounds CeT$_2$Al$_{10}$ (T = Ru and Os) is followed by antiferromagnetic ordering at $T_N$ = 27 K and 28.5 K, respectively, with a small ordered moment (0.29$-$0.34$μ_B$) along the $c-$axis, which is not an easy axis of the crystal field (CEF). In order to investigate how the moment direction and the spin gap energy change with 10\% La doping in Ce$_{1-x}$La$_x$T$_2$Al$_{10}$ (T = Ru and Os) and also to understand the microscopic nature of the magnetic ground state, we here report on magnetic, transport, and thermal properties, neutron diffraction (ND) and inelastic neutron scattering (INS) investigations on these compounds. Our INS study reveals the persistence of spin gaps of 7 meV and 10 meV in the 10\% La-doped T = Ru and Os compounds, respectively. More interestingly our ND study shows a very small ordered moment of 0.18 $μ_B$ along the $b-$axis (moment direction changed compared with the undoped compound), in Ce$_{0.9}$La$_{0.1}$Ru$_2$Al$_{10}$, however a moment of 0.23 $μ_B$ still along the $c-$axis in Ce$_{0.9}$La$_{0.1}$Os$_2$Al$_{10}$. This contrasting behavior can be explained by a different degree of hybridization in CeRu$_2$Al$_{10}$ and CeOs$_2$Al$_{10}$, being stronger in the latter than in the former. Muon spin rotation ($μ$SR) studies on Ce$_{1-x}$La$_x$Ru$_2$Al$_{10}$ ($x$ = 0, 0.3, 0.5 and 0.7), reveal the presence of coherent frequency oscillations indicating a long$-$range magnetically ordered ground state for $x$ = 0 to 0.5, but an almost temperature independent Kubo$-$Toyabe response between 45 mK and 4 K for $x$ = 0.7. We will compare the results of the present investigations with those reported on the electron and hole$-$doping in CeT$_2$Al$_{10}$.
description: 11 pages, 7 figures
The N5K Challenge: Non-Limber Integration for LSST Cosmology
Creators: name: Leonard, C. D.
name: Ferreira, T.
name: Fang, X.
name: Reischke, R.
name: Schoeneberg, N.
name: Tröster, T.
name: Alonso, D.
name: Campagne, J. E.
name: Lanusse, F.
name: Slosar, A.
name: Ishak, M.
name: Collaboration, the LSST Dark Energy Science
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The rapidly increasing statistical power of cosmological imaging surveys requires us to reassess the regime of validity for various approximations that accelerate the calculation of relevant theoretical predictions. In this paper, we present the results of the 'N5K non-Limber integration challenge', the goal of which was to quantify the performance of different approaches to calculating the angular power spectrum of galaxy number counts and cosmic shear data without invoking the so-called 'Limber approximation', in the context of the Rubin Observatory Legacy Survey of Space and Time (LSST). We quantify the performance, in terms of accuracy and speed, of three non-Limber implementations: ${\tt FKEM (CosmoLike)}$, ${\tt Levin}$, and ${\tt matter}$, themselves based on different integration schemes and approximations. We find that in the challenge's fiducial 3x2pt LSST Year 10 scenario, ${\tt FKEM (CosmoLike)}$ produces the fastest run time within the required accuracy by a considerable margin, positioning it favourably for use in Bayesian parameter inference. This method, however, requires further development and testing to extend its use to certain analysis scenarios, particularly those involving a scale-dependent growth rate. For this and other reasons discussed herein, alternative approaches such as ${\tt matter}$ and ${\tt Levin}$ may be necessary for a full exploration of parameter space. We also find that the usual first-order Limber approximation is insufficiently accurate for LSST Year 10 3x2pt analysis on $\ell=200-1000$, whereas invoking the second-order Limber approximation on these scales (with a full non-Limber method at smaller $\ell$) does suffice.
description: 15 pages, 8 figures. Journal-accepted version
Engineering High Content and Multicellular Human Liver Platforms for Drug Development
Creators: name: Monckton, Chase Paul
Publisher: name: University of Illinois at Chicago
Year: 2022
Subjects: Uncategorized

description: The diverse functions of the liver can be severely compromised by several diseases (e.g., non-alcoholic fatty liver disease and hepatitis C/B virus infections); furthermore, drug-induced liver injury is a leading cause of preclinical/clinical drug attrition and acute liver failure. While animal models are utilized to investigate disease mechanisms and screen drugs, there are significant differences between animals and humans in the liver’s molecular pathways. Therefore, there have been increased efforts over the last decade to develop in vitro models of the human liver using primary human liver cells and, more recently, induced pluripotent stem cell-derived hepatocyte-like cells (iHeps). However, there is a need to fully decipher the biophysical and biochemical microenvironmental cues that modulate hepatic functions and regeneration in physiologic and diseased contexts. Unfortunately, using traditional cell culture techniques is too slow and costly to explore such microenvironments in a combinatorial manner. In contrast, high-throughput cellular microarrays that enable precise and independent control over the extracellular matrix (ECM) protein composition and stiffness can be used to elucidate how these parameters affect cell function. Similarly, micropatterning primary human hepatocytes (PHHs) in coculture with supporting non-parenchymal cell (NPC) types enables precise manipulation of homotypic and heterotypic cell-cell interactions toward determining effects on cell’s phenotypic longevity. This thesis aims to adapt these tools to address fundamental gaps in the field of in vitro human liver models. First, high-throughput cell microarrays are being used to determine how ECM protein composition and stiffness act independently and in synergistic combinations to regulate the functions of PHHs and iHeps over at least 2 weeks in culture. Second, micropatterned cocultures are used to elucidate the role of liver NPCs in the modulation of long-term hepatic functions and reciprocal effects on NPCs. Third, soluble factors (e.g., growth factors and small molecules that modulate key liver pathways) are used to devise strategies to regenerate PHHs in vitro towards mimicking the impressive proliferative potential of these cells in vivo. In conclusion, this thesis will explore for the first time how precisely controlled biophysical, biochemical, and cellular factors affect human hepatic functions or mimic regeneration towards improving platforms for drug development and, ultimately, regenerative medicine.
57Fe Mossbauer study of Lu2Fe3Si5 iron silicide superconductor
Creators: name: Ma, Xiaoming
name: Ran, Sheng
name: Pang, Hua
name: Li, Fashen
name: Canfield, Paul C.
name: Bud'ko, Sergey L.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: With the advent of Fe-As based superconductivity it has become important to study how superconductivity manifests itself in details of 57Fe Mossbauer spectroscopy of conventional, Fe - bearing superconductors. To this end, the iron-based superconductor Lu2Fe3Si5 has been studied by 57Fe Mossbauer spectroscopy over the temperature range from 4.4 K to room temperature with particular attention to the region close to the superconducting transition temperature (Tc = 6.1 K). Consistent with the two crystallographic sites for Fe in this structure, the observed spectra appear to have a pattern consisting of two doublets over the whole temperature range. The value of Debye temperature was estimated from temperature dependence of the isomer shift and the total spectral area and compared with the specific heat capacity data. Neither abnormal behavior of the hyperfine parameters at or near Tc, nor phonon softening were observed.
description: mistake with references corrected
Supplementary document for Tunable in situ Near-UV Pulses by Transient Plasmonic Resonance in Nanocomposites - 6626266.pdf
Creators: name: Husakou, Anton
name: Babushkin, Ihar
name: Fedotova, Olga
name: Rusetsky, Ryhor
name: Smirnova, Tatsiana
name: Khasanov, Oleg
name: Fedotov, Alexander
name: Sapaev, Usman
name: Apostolova, Tzveta
Publisher: name: Optica Publishing Group
Year: 2023
Subjects: Uncategorized

description: Supplemental description of the theoretical and numerical model
Massive to Massless by Applying a Nonlocal Field Redefinition
Creators: name: Najafizadeh, Mojtaba
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: The invariance of physical observables like particle's mass under a local field redefinition is a well-known and important property of quantum field theory. In this paper, on the other hand, we investigate nonlocal field redefinitions eliminating a physical observable from a theory. Indeed, by giving explicit examples, we present invertible nonlocal field redefinitions reducing a massive theory to the massless one, and vice versa. The studied examples are: classical harmonic oscillator, the scalar field theory, and the Dirac field theory.
description: 11 pages, no figure. v2: references and clarifications added, v3: matches published version in PRD
VEGF-induced Rac1 activation in endothelial cells is regulated by the guanine nucleotide exchange factor Vav2
Creators: name: Van Buul, Jaap D.
name: Burridge, Keith
name: Garrett, Tiana A.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2007

description: Vascular endothelial growth factor (VEGF) signaling is critical for both normal and disease-associated vascular development. Dysregulated VEGF signaling has been implicated in ischemic stroke, tumor angiogenesis, and many other vascular diseases. VEGF signals through several effectors, including the Rho family of small GTPases. As a member of this family, Rac1 promotes VEGF-induced endothelial cell migration by stimulating the formation of lamellipodia and membrane ruffles. To form these membrane protrusions, Rac1 is activated by guanine nucleotide exchange factors (GEFs) that catalyze the exchange of GDP for GTP. The goal of this study was to identify the GEF responsible for activating Rac1 in response to VEGF stimulation. We have found that VEGF stimulates biphasic activation of Rac1 and for these studies we focused on the peak of activation that occurs at 30 min. Inhibition of VEGFR-2 signaling blocks VEGF-induced Rac1 activation. Using a Rac1 nucleotide-free mutant (G15ARac1), which has a high affinity for binding activated GEFs, we show that the Rac GEF Vav2 associates with G15ARac1 after VEGF stimulation. Additionally, we show that depleting endothelial cells of endogenous Vav2 with siRNA prevents VEGF-induced Rac1 activation. Moreover, Vav2 is tyrosine phosphorylated upon VEGF treatment, which temporally correlates with Rac1 activation and requires VEGFR-2 signaling and Src kinase activity. Finally, we show that depressing Vav2 expression by siRNA impairs VEGF-induced endothelial cell migration. Taken together, our results provide evidence that Vav2 acts downstream of VEGF to activate Rac1.
AdS (In)stability: Lessons From The Scalar Field
Creators: name: Basu, Pallab
name: Krishnan, Chethan
name: Subramanian, P. N. Bala
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We argued in arXiv:1408.0624 that the quartic scalar field in AdS has features that could be instructive for answering the gravitational stability question of AdS. Indeed, the conserved charges identified there have recently been observed in the full gravity theory as well. In this paper, we continue our investigation of the scalar field in AdS and provide evidence that in the Two-Time Formalism (TTF), even for initial conditions that are far from quasi-periodicity, the energy in the higher modes at late times is exponentially suppressed in the mode number. Based on this and some related observations, we argue that there is no thermalization in the scalar TTF model within time-scales that go as $\sim 1/ε^2$, where $ε$ measures the initial amplitude (with only low-lying modes excited). It is tempting to speculate that the result holds also for AdS collapse.
description: 10 pages, 4 figures
Focal Adhesion Kinase regulates cell–cell contact formation in epithelial cells via modulation of Rho
Creators: name: CAI, X
name: SCHALLER, M
name: BURRIDGE, K
name: VADALI, K
name: PLAYFORD, M
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Focal Adhesion Kinase (FAK) is a non-receptor tyrosine kinase that plays a key role in cellular processes such as cell adhesion, migration, proliferation and survival. Recent studies have also implicated FAK in the regulation of cell-cell adhesion. Here, evidence is presented showing that siRNA-mediated suppression of FAK levels in NBT-II cells and expression of dominant negative mutants of FAK caused loss of epithelial cell morphology and inhibited the formation of cell-cell adhesions. Rac and Rho have been implicated in the regulation of cell-cell adhesions and can be regulated by FAK signaling. Expression of active Rac or Rho in NBT-II cells disrupted formation of cell-cell contacts, thus promoting a phenotype similar to FAK-depleted cells. The loss of intercellular contacts in FAK-depleted cells is prevented upon expression of a dominant negative Rho mutant, but not a dominant negative Rac mutant. Inhibition of FAK decreased tyrosine phosphorylation of p190RhoGAP and elevated the level of GTP-bound Rho. This suggests that FAK regulates cell-cell contact formation by regulation of Rho.
RhoA/ROCK-mediated switching between Cdc42- and Rac1-dependent protrusion in MTLn3 carcinoma cells
Creators: name: Pertz, Olivier
name: El-Sibai, Mirvat
name: Condeelis, John S.
name: Backer, Jonathan M.
name: Pang, Huan
name: Symons, Marc
name: Yip, Shu-Chin
name: Hahn, Klaus M.
name: Lorenz, Mike
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Rho GTPases are versatile regulators of cell shape that act on the actin cytoskeleton. Studies using Rho GTPase mutants have shown that, in some cells, Rac1 and Cdc42 regulate the formation of lamellipodia and filopodia, respectively at the leading edge, whereas RhoA mediates contraction at the rear of moving cells. However, recent reports have described a zone of RhoA/ROCK activation at the front of cells undergoing motility. In this study, we use a FRET-based RhoA biosensor to show that RhoA activation localizes to the leading edge of EGF-stimulated cells. Inhibition of Rho or ROCK enhanced protrusion, yet markedly inhibited cell motility; these changes correlated with a marked activation of Rac-1 at the cell edge. Surprisingly, whereas EGF-stimulated protrusion in control MTLn3 cells is Rac-independent and Cdc42-dependent, the opposite pattern is observed in MTLn3 cells after inhibition of ROCK. Thus, Rho and ROCK suppress Rac-1 activation at the leading edge, and inhibition of ROCK causes a switch between Cdc42 and Rac-1 as the dominant Rho GTPase driving protrusion in carcinoma cells. These data describe a novel role for Rho in coordinating signaling by Rac and Cdc42.
Finite temperature energy-momentum tensor in compactified cosmic string spacetime
Creators: name: Santos, W. Oliveira dos
name: de Mello, E. R. Bezerra
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper we analyze the expectation value of the field squared and the energy-momentum tensor associated with a massive charged scalar quantum field with a nonzero chemical potential propagating in a high-dimensional compactified cosmic string spacetime in thermal equilibrium at finite temperature $T$. Moreover, we assume that the charged quantum field interacts with a very thin magnetic flux running along the core of the idealized cosmic string, and with a magnetic flux enclosed by the compact dimension. These observables are expressed as the vacuum expectation values and the finite temperature contributions coming from the particles and antiparticles excitations. Due to the compactification, the thermal corrections can be decomposed in a part induced by the cosmic string spacetime without compactification, plus a contribution induced by the compactification. This decompositions explicitly follows from the Abel-Plana formula used to proceed the summation over the discrete quantum number associated with the quasiperiodic condition imposed on the quantum field along the compact dimension. The expectations values of the field squared and the energy-momentum tensor are even periodic functions of the magnetic flux with period being the quantum flux, and also even functions of the chemical potential. Our main objectives in this paper concern in the investigation of the thermal corrections only. In this way we explicitly calculate the behavior of these observables in the limits of low and high temperature. We show that the temperature enhance the induced densities. In addition some graphs are also included in order to exhibit these behaviors.
description: 23 pages, 5 figures; Version accepted for publication in EPJC
MPEC 2023-U125 : 2023 UJ2
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 UJ2

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Renormalization in Wavelet basis
Creators: name: Basak, Mrinmoy
name: Ratabole, Raghunath
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Discrete wavelet-based methods promise to emerge as an excellent framework for the non-perturbative analysis of quantum field theories. In this work, we investigate aspects of renormalization in theories analyzed using wavelet-based methods. We demonstrate the non-perturbative approach of regularization, renormalization, and the emergence of flowing coupling constant within the context of these methods. This is tested on a model of the particle in an attractive Dirac delta function potential in two spatial dimensions, which is known to demonstrate quintessential features found in a typical relativistic quantum field theory.
ERBBs in the gastrointestinal tract: Recent progress and new perspectives
Creators: name: Coffey, Robert J.
name: Fiske, William H.
name: Threadgill, David
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: The gastrointestinal epithelium does much more than provide a physical barrier between the intestinal lumen and our internal milieu. It is actively engaged in absorption and secretion of salt and water via ion transporters, exchangers and selective ion channels. It is also a continuously self-renewing epithelium that undergoes ordered growth and differentiation along its vertical axis. From this dual perspective, we will consider the actions of the ERBB family of ligands and receptors in the maintenance of gastrointestinal homeostasis and discuss instances when the actions of this family go awry such as in cancer and Ménétrier's disease.
Computational Aspects of the Colorful Carathéodory Theorem
Creators: name: Mulzer, Wolfgang
name: Stein, Yannik
Publisher: name: arXiv
Year: 2014
Subjects: subject: Computational Geometry (cs.CG)
subject: FOS: Computer and information sciences

description: Let $C_1,\dots,C_{d+1}\subset \mathbb{R}^d$ be $d+1$ point sets, each containing the origin in its convex hull. We call these sets color classes, and we call a sequence $p_1, \dots, p_{d+1}$ with $p_i \in C_i$, for $i = 1, \dots, d+1$, a colorful choice. The colorful Carathéodory theorem guarantees the existence of a colorful choice that also contains the origin in its convex hull. The computational complexity of finding such a colorful choice (CCP) is unknown. This is particularly interesting in the light of polynomial-time reductions from several related problems, such as computing centerpoints, to CCP. We define a novel notion of approximation that is compatible with the polynomial-time reductions to CCP: a sequence that contains at most $k$ points from each color class is called a $k$-colorful choice. We present an algorithm that for any fixed $\varepsilon > 0$, outputs an $\lceil εd\rceil$-colorful choice containing the origin in its convex hull in polynomial time. Furthermore, we consider a related problem of CCP: in the nearest colorful polytope problem (NCP), we are given sets $C_1,\dots,C_n\subset\mathbb{R}^d$ that do not necessarily contain the origin in their convex hulls. The goal is to find a colorful choice whose convex hull minimizes the distance to the origin. We show that computing a local optimum for NCP is PLS-complete, while computing a global optimum is NP-hard.
description: 28 pages, 7 figures. A preliminary version appeared at SoCG 2015
Estimation of the Shear Modulus of Isotropic Materials from SLDV via Convolutional Neural Network
Creators: name: Leccabue, Silvia
Publisher: name: University of Illinois at Chicago
Year: 2022
Subjects: Uncategorized

description: Nowadays, research provides growing evidence about the importance of having tissue mechanical property values available as a parameter for diagnosis because tissue mechanical properties are sensitive to pathological changes. This behavior is the basis for using elastography as a diagnostic tool. The approach used to measure wave propagation in this work is a dynamic elastography technique called Scanning Laser Doppler Vibrometry (SLDV). Since several studies demonstrated the ability of Convolutional Neural Networks (CNNs) to automatically and robustly assess mechanical properties from elastography images overcoming the limitations of the traditional inversion techniques, this thesis aims to estimate the stiffness from silicon-based materials SLDV images through an implemented CNN. During the analysis, the use of soft tissue-mimicking materials as the EcoflexTM allowed us to perform the evaluations on some materials that realistically simulate the properties of soft tissues, exhibiting similar deformation responses and stiffness values. The classification of the shear modulus of the materials was performed on two separate tasks, a binary classification and a more complex five classes classification. The proposed CNN architecture was pre-trained using synthetic wave data generated using a computational model and afterwards the model was fine-tuned with the physical data. During the two experiments using physical data, the binary classification achieves an accuracy= 84.4%, and the multi-class classification reports an accuracy of 76,6%. CNN architecture is able to distinguish all the different materials, showing a significant rate of well-predicted data concerning both the simulation of healthy and pathological samples (binary classification) and also more intermediate stages of a specific pathology (five-classes classification), where the discriminant features are the changes in the wave propagation speed and the correlated shear modulus. Although not yet allowing a clinical application for the estimation of the stiffness of organs and soft tissues, these results constitute a step forward towards the implementation of an automatic and reliable method for assessing mechanical properties from elastography images.
p190RhoGAP negatively regulates Rho activity at the cleavage furrow of mitotic cells
Creators: name: Pertz, Olivier
name: Mikawa, Masahito
name: Parsons, Sarah J.
name: Su, Ling
name: Hahn, Klaus
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: Previous studies demonstrated that p190RhoGAP (p190) negatively affects cytokinesis in a Rho-GAP-dependent manner, suggesting that regulation of Rho may be a critical mechanism of p190 action during cytokinesis. P190 localizes to the cleavage furrow (CF) of dividing cells, and its levels decrease during late mitosis by an ubiquitin-mediated mechanism, consistent with the hypothesis that high RhoGTP levels are required for completion of cytokinesis. To determine whether RhoGTP levels in the CF are affected by p190 and to define the phase(s) of cytokinesis in which p190 is involved, we used FRET analysis alone or in combination with time lapse microscopy. In normal cell division activated Rho accumulated at the cell equator in early anaphase and in the contractile ring, where it co-localized with p190. Real-time movies revealed that cells expressing elevated levels of p190 exhibited multiple cycles of abnormal CF site selection and ingression/regression, which resulted in failed or prolonged cytokinesis. This was accompanied by mislocalization of active Rho at the aberrant CF sites. Quantified data revealed that in contrast to ECT2 and dominate negative p190 (Y1283Ap190), which resulted in hyper-activated Rho, Rho activity in the CF was reduced by wild type p190 in a dose-dependent manner. These results suggest that p190 regulates cytokinesis through modulation of Rho-GTP levels, thereby affecting CF specification site selection and subsequent ring contraction.
PKCα tumor suppression in the intestine is associated with transcriptional and translational inhibition of cyclin D1
Creators: name: Robine, Sylvie
name: Black, Adrian R.
name: Velcich, Anna
name: Leontieva, Olga V.
name: Uronis, Joshua M.
name: Bateman, Nicholas W.
name: Pysz, Marybeth A.
name: Black, Jennifer D.
name: Augenlicht, Leonard H.
name: Threadgill, David W.
name: Curry, Kathryn J.
name: Janssen, Klaus-Peter
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2009

description: Alterations in PKC isozyme expression and aberrant induction of cyclin D1 are early events in intestinal tumorigenesis. Previous studies have identified cyclin D1 as a major target in the antiproliferative effects of PKCα in non-transformed intestinal cells; however, a link between PKC signaling and cyclin D1 in colon cancer remained to be established. The current study further characterized PKC isozyme expression in intestinal neoplasms and explored the consequences of restoring PKCα or PKCδ in a panel of colon carcinoma cell lines. Consistent with patterns of PKC expression in primary tumors, PKCα and δ levels were generally reduced in colon carcinoma cell lines, PKCβII was elevated and PKCε showed variable expression, thus establishing the suitability of these models for analysis of PKC signaling. While colon cancer cells were insensitive to the effects of PKC agonists on cyclin D1 levels, restoration of PKCα downregulated cyclin D1 by two independent mechanisms. PKCα expression consistently (a) reduced steady-state levels of cyclin D1 by a novel transcriptional mechanism not previously seen in non-transformed cells, and (b) re-established the ability of PKC agonists to activate the translational repressor 4E-BP1 and inhibit cyclin D1 translation. In contrast, PKCδ had modest and variable effects on cyclin D1 steady state levels and failed to restore responsiveness to PKC agonists. Notably, PKCα expression blocked anchorage-independent growth in colon cancer cells via a mechanism partially dependent on cyclin D1 deficiency, while PKCδ had only minor effects. Loss of PKCα and effects of its re-expression were independent of the status of the APC/β-catenin signaling pathway or known genetic alterations, indicating that they are a general characteristic of colon tumors. Thus, PKCα is a potent negative regulator of cyclin D1 expression and anchorage-independent cell growth in colon tumor cells, findings that offer important perspectives on the frequent loss of this isozyme during intestinal carcinogenesis.
MPEC 2023-U126 : 2023 UK2
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 UK2

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
The Prym map of degree-7 cyclic coverings
Creators: name: Lange, Herbert
name: Ortega, Angela
Publisher: name: arXiv
Year: 2015
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We study the Prym map for degree-7 etale cyclic coverings over a curve of genus 2. We extend this map to a proper map on a partial compactification of the moduli space of such coverings, and prove that the Prym map is generically finite onto its image of degree 10.
description: 22 pages, 1 figure
Activated protein C enhances cell motility of endothelial cells and MDA-MB-231 breast cancer cells by intracellular signal transduction
Creators: name: Beaulieu, Lea M.
name: Gramling, Mark W.
name: Church, Frank C.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2010

description: Activated protein C (APC), an anticoagulant serine protease, has been shown to have non-hemostatic functions related to inflammation, cell survival, and cell migration. In this study we investigate the mechanism by which APC promotes angiogenesis and breast cancer invasion using ex vivo and in vitro methods. When proteolytically active, APC promotes cell motility/invasion and tube formation of endothelial cells. Ex vivo aortic ring assays verify the role of APC in promoting angiogenesis, which was determined to be dependent on EGFR and MMP activation. Given the capacity of APC to promote angiogenesis and the importance of this process in cancer pathology, we investigated whether the mechanisms by which APC promotes angiogenesis can also promote motility and invasion in the MDA-MB-231 breast cancer cell line. Our results indicate that, extracellularly, APC engages EPCR, PAR-1, and EGFR in order to increase the invasiveness of MDA-MB-231 cells. APC activation of matrix metalloprotease (MMP) -2 and/or -9 is necessary but not sufficient to increase invasion, and APC does not utilize the endogenous plasminogen activation system to increase invasion. Intracellularly, APC activates ERK, Akt, and NFκB, but not the JNK pathway to promote MDA-MB-231 cell motility. Similar to the hemostatic protease thrombin, APC has the ability to enhance both endothelial cell motility/angiogenesis and breast cancer cell migration.
The regulation of RhoA at focal adhesions by StarD13 is important for astrocytoma cell motility
Creators: name: El-Sabban, Marwan
name: Khalil, Bassem D.
name: Symons, Marc
name: Marston, Daniel
name: Hanna, Samer
name: El-Sibai, Mirvat
name: El-Sitt, Sally
name: Nasrallah, Anita
name: Saykali, Bechara A.
name: Hahn, Klaus M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Malignant astrocytomas are highly invasive into adjacent and distant regions of the normal brain. Rho GTPases are small monomeric G proteins that play important roles in cytoskeleton rearrangement, cell motility, and tumor invasion. In the present study, we show that the knock down of StarD13, a GTPase activating protein (GAP) for RhoA and Cdc42, inhibits astrocytoma cell migration through modulating focal adhesion dynamics and cell adhesion. This effect is mediated by the resulting constitutive activation of RhoA and the subsequent indirect inhibition of Rac. Using Total Internal Reflection Fluorescence (TIRF)-based Förster Resonance Energy Transfer (FRET), we show that RhoA activity localizes with focal adhesions at the basal surface of astrocytoma cells. Moreover, the knock down of StarD13 inhibits the cycling of RhoA activation at the rear edge of cells, which makes them defective in retracting their tail. This study highlights the importance of the regulation of RhoA activity in focal adhesions of astrocytoma cells and establishes StarD13 as a GAP playing a major role in this process.
Myosin-X and disease
Creators: name: Cheney, Richard E.
name: Courson, David S.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: Myosin-X (Myo10) is a motor protein well known for its role in filopodia formation. New research implicates Myo10 in a number of disease states including cancer metastasis and pathogen infection. This review focuses on these developments with emphasis on the emerging roles of Myo10 in formation of cancer cell protrusions and metastasis. A number of aggressive cancers show high levels of Myo10 expression and knockdown of Myo10 has been shown to dramatically limit cancer cell motility in 2D and 3D systems. Myo10 knockdown also limits spread of intracellular pathogens marburgvirus and Shigella flexneri. Consideration is given to how these properties might arise and potential paths of future research.