cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Classical Heisenberg Model on the Centred Pyrochlore Lattice
Creators: name: Nutakki, Rajah P.
name: Jaubert, Ludovic D. C.
name: Pollet, Lode
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The centred pyrochlore lattice is a novel geometrically frustrated lattice, realized in the metal-organic framework Mn(ta)$_2$ (arXiv:2203.08780) where the basic unit of spins is a five site centred tetrahedron. Here, we present an in-depth theoretical study of the $J_1-J_2$ classical Heisenberg model on this lattice, using a combination of mean-field analytical methods and Monte Carlo simulations. We find a rich phase diagram with low temperature states exhibiting ferrimagnetic order, partial ordering, and a highly degenerate spin liquid with distinct regimes of low temperature correlations. We discuss in detail how the regime displaying broadened pinch points in its spin structure factor is consistent with an effective description in terms of a fluid of interacting charges. We also show how this picture holds in two dimensions on the analogous centred kagome lattice and elucidate the connection to the physics of thin films in ($d+1$) dimensions. Furthermore, we show that a Coulomb phase can be stabilized on the centred pyrochlore lattice by the addition of further neighbour couplings. This demonstrates the centred pyrochlore lattice is an experimentally relevant geometry which naturally hosts emergent gauge fields in the presence of charges at low energies.
description: 29 pages, 9 figures, resubmission to SciPost with minor revisions
Visible Photolysis and Amperometric Detection of S -Nitrosothiols
Creators: name: Schoenfisch, Mark H.
name: Riccio, Daniel A.
name: Nutz, Steven T.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2012

description: The concentration of S-nitrosothiols (RSNOs), endogenous transporters of the signaling molecule nitric oxide (NO), fluctuate greatly in physiology often as a function of disease state. RSNOs may be measured indirectly by cleaving the S–N bond and monitoring the liberated NO. While ultraviolet photolysis and reductive-based cleavage both decompose RSNOs to NO, poor selectivity and the need for additional reagents preclude their utility clinically. Herein, we report the coupling of visible photolysis (i.e., 500–550 nm) and amperometric NO detection to quantify RSNOs with greater selectivity and sensitivity. Enhanced sensitivity (up to 1.56 nA µM−1) and lowered theoretical detection limits (down to 30 nM) were achieved for low molecular weight RSNOs (i.e., S-nitrosoglutathione, S-nitrosocysteine) by tuning the irradiation exposure. Detection of nitrosated proteins (i.e., S-nitrosoalbumin) was also possible, albeit at a decreased sensitivity (0.11 nA µM−1). This detection scheme was used to measure RSNOs in plasma and illustrate the potential of this method for future physiological studies.
MPEC 2023-Q142 : COMET P/2014 W1 = P/2023 O2 (PANSTARRS)
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: COMET P/2014 W1 = P/2023 O2 (PANSTARRS)

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.
Actinide ions for testing the spatial $α-$variation hypothesis
Creators: name: Dzuba, V. A.
name: Safronova, M. S.
name: Safronova, U. I.
name: Flambaum, V. V.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Testing the spatial variation of fine-structure constant $α$ indicated in [Webb et al., Phys. Rev. Lett. 107, 191101 (2011)] with terrestrial laboratory atomic measurements requires at least $\dotα/α\sim 10^{-19}~\textrm{y}^{-1}$ sensitivity. We conduct a systematic search of atomic systems for such a test that have all features of the best optical clock transitions leading to possibility of the frequency measurements with fractional accuracy on the level of $10^{-18}$ or better and have a factor of 100 extra enhancement of $α$-variation in comparisons to experimental frequency ratio measurement accuracy. We identify the pair of actinide Cf$^{15+}$ and Es$^{16+}$ ions as the best system for a test of spatial $α-$variation hypothesis as it satisfies both of these requirements and have sufficiently simple electronic structure to allow for high-precision predictions of all atomic properties required for rapid experimental progress.
description: 5 pages, 2 figures
Transfer of immoveables in a European perspective
Creators: name: Pradi, Andrea
Publisher: name: Universit� degli Studi di Trento
Year: 2015

description: The issue of the transfer of immoveable is at the core of the process of harmonization of European law, despite the legal regime of property is formally excluded from the influence of European law. When dealing with the transfer of property rights, legal systems aim at creating a legal framework for the market which is twofold: increasing its efficiency while preserving legal certainty. Despite their difference in legal design, it may be easily observed that in order to secure market transactions European legal systems have surrounded transfer with legal institution functioning as a gatekeeper of legality and certainty such as contractual formalities, notarial body, land registers. These institutions have been developed over the time and they cannot be easily simplified or even eliminated. It is the role of a reliable comparative legal work to understand how the different legal systems have reached such an equilibrium over the years, how and why they have translated it into their legal rules, and how these principles and rules are working in practice.
Low-complexity linear parameter-varying approximations of incompressible Navier-Stokes equations for truncated state-dependent Riccati feedback
Creators: name: Heiland, Jan
name: Werner, Steffen W. R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optimization and Control (math.OC)
subject: Numerical Analysis (math.NA)
subject: Dynamical Systems (math.DS)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: Nonlinear feedback design via state-dependent Riccati equations is well established but unfeasible for large-scale systems because of computational costs. If the system can be embedded in the class of linear parameter-varying (LPV) systems with the parameter dependency being affine-linear, then the nonlinear feedback law has a series expansion with constant and precomputable coefficients. In this work, we propose a general method to approximating nonlinear systems such that the series expansion is possible and efficient even for high-dimensional systems. We lay out the stabilization of incompressible Navier-Stokes equations as application, discuss the numerical solution of the involved matrix-valued equations, and confirm the performance of the approach in a numerical example.
description: 8 pages, 3 figures
Are third-party interventions in civil wars desirable? A multi-method approach to ending intrastate conflicts
Creators: name: Bredikova, Hana
Publisher: name: Universit� degli studi di Trento
Year: 2019

description: This dissertation examines the effectiveness and political support surrounding third-party interventions in civil wars, which have increased in frequency, type, and number of actors since the collapse of Cold War bipolarity. The existing literature has mainly examined the individual effects of third-party strategies, though the growing presence of concurrently occurring types of third-party interventions necessitates exploration of their interactive effects. Thus, this thesis seeks to understand different actions from multiple actors dependently rather than independently. Understanding the effectiveness of these strategies is only one step towards realizing whether third-party interventions are desirable. The motivation and the will of the actors responsible for the policy execution are crucial in realizing the full picture. The ubiquitous problem arising from the third-party interventions requires a multipronged methodological approach. This thesis, therefore, combines both observational and experimental data to explore this issue. While the primary results show that peacekeeping and mediation are the most effective and supported strategies of engagement, both effectiveness and support appear to be highly context-dependent. Further, this thesis surveys American public and political elites to delve into the determinants of support for third-party interventions. It nds that both the public and the political elite are sensitive to civilian casualties, yet in the face of a political rivalry these humanitarian concerns dissipate. Additionally, political elites are interested in ending hostilities only as long as their national security interests are at stake. By filling a gap in the literature, generating original data, and utilizing novel methodological approach, these results have underlined the need for improvement of policy decisions in the area of international confict management and, at the same time, build upon the new direction of research in the eld of confict dynamics.
(100697) Susan Anna Beatty
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
Voltage equilibration for reactive atomistic simulations of electrochemical processes
Creators: name: Onofrio, Nicolas
name: Strachan, Alejandro
Publisher: name: arXiv
Year: 2015
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We introduce EChemDID, a model to describe electrochemical driving force in reactive molecular dynamics simulations. The method describes the equilibration of external electrochemical potentials (voltage) within metallic structures and their effect on the self consistent partial atomic charges used in reactive molecular dynamics. An additional variable assigned to each atom denotes the local potential in its vicinity and we use fictitious, but computationally convenient, dynamics to describe its equilibration within not-simply connected metallic structures on-the-fly during the molecular dynamics simulation. This local electrostatic potential is used to dynamically modify the atomic electronegativities used to compute partial atomic changes via charge equilibration. Validation tests show that the method provides an accurate description of the electric fields generated by the applied voltage and the driving force for electrochemical reactions. We demonstrate EChemDID via simulations of the operation of electrochemical metallization cells. The simulations predict the switching of the device between a high-resistance to a low-resistance state as a conductive metallic bridge is formed and resistive currents that can be compared with experimental measurements. In addition to applications in nanoelectronics, EChemDID could be useful to model electrochemical energy conversion devices.
description: 19 pages, 5 figures
The 300 pc resolution imaging of a z = 8.31 galaxy: Turbulent ionized gas and potential stellar feedback 600 million years after the Big Bang
Creators: name: Tamura, Yoichi
name: Bakx, Tom J. L. C.
name: Inoue, Akio K.
name: Hashimoto, Takuya
name: Tokuoka, Tsuyoshi
name: Imamura, Chihiro
name: Hatsukade, Bunyo
name: Lee, Minju M.
name: Moriwaki, Kana
name: Okamoto, Takashi
name: Ota, Kazuaki
name: Umehata, Hideki
name: Yoshida, Naoki
name: Zackrisson, Erik
name: Hagimoto, Masato
name: Matsuo, Hiroshi
name: Shimizu, Ikkoh
name: Sugahara, Yuma
name: Takeuchi, Tsutomu T.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the results of 300 pc resolution ALMA imaging of the [OIII] 88 $μ$m line and dust continuum emission from a $z = 8.312$ Lyman break galaxy MACS0416_Y1. The velocity-integrated [OIII] emission has three peaks which are likely associated with three young stellar clumps of MACS0416_Y1, while the channel map shows a complicated velocity structure with little indication of a global velocity gradient unlike what was found in [CII] 158 $μ$m at a larger scale, suggesting random bulk motion of ionized gas clouds inside the galaxy. In contrast, dust emission appears as two individual clumps apparently separating or bridging the [OIII]/stellar clumps. The cross correlation coefficient between dust and ultraviolet-related emission (i.e., [OIII] and ultraviolet continuum) is unity on a galactic scale, while it drops at < 1 kpc, suggesting well mixed geometry of multi-phase interstellar media on sub-kpc scales. If the cutoff scale characterizes different stages of star formation, the cutoff scale can be explained by gravitational instability of turbulent gas. We also report on a kpc-scale off-center cavity embedded in the dust continuum image. This could be a superbubble producing galactic-scale outflows, since the energy injection from the 4 Myr starburst suggested by a spectral energy distribution analysis is large enough to push the surrounding media creating a kpc-scale cavity.
description: 18 pages, 6 figures, 1 table, published in ApJ
An Approach for Separation and Complete Structural Sequencing of Heparin/Heparan Sulfate-like Oligosaccharides
Creators: name: Sharp, Joshua S.
name: Huang, Rongrong
name: Liu, Jian
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: As members of the glycosaminoglycan (GAG) family, heparin and heparan sulfate (HS) are responsible for mediation of a wide range of essential biological actions, most of which are mediated by specific patterns of modifications of regions of these polysaccharides. To fully understand the regulation of HS modification and the biological function of HS through its interactions with protein ligands, it is essential to know the specific HS sequences present. However, the sequencing of mixtures of HS oligosaccharides presents major challenges due to the lability of the sulfate modifications, as well as difficulties in separating isomeric HS chains. Here, we apply a sequential chemical derivatization strategy involving permethylation, desulfation and trideuteroperacetylation to label original sulfation sites with stable and hydrophobic trideuteroacetyl groups. The derivatization chemistry differentiates between all possible heparin/HS sequences solely by glycosidic bond cleavages, without the need to generate cross-ring cleavages. This derivatization strategy combined with LC-MS/MS analysis has been used to separate and sequence five synthetic HS-like oligosaccharides of sizes up to dodecasaccharide, as well as a highly-sulfated Arixtra-like heptamer. This strategy offers a unique capability for the sequencing of microgram quantities of HS oligosaccharide mixtures by LC-MS/MS.
Higher Sugawara operators for the quantum affine algebras of type A
Creators: name: Frappat, Luc
name: Jing, Naihuan
name: Molev, Alexander
name: Ragoucy, Eric
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Algebra (math.QA)
subject: Mathematical Physics (math-ph)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We give explicit formulas for the elements of the center of the completed quantum affine algebra in type $A$ at the critical level which are associated with the fundamental representations. We calculate the images of these elements under a Harish-Chandra-type homomorphism. These images coincide with those in the free field realization of the quantum affine algebra and reproduce generators of the $q$-deformed classical $W$-algebra of Frenkel and Reshetikhin.
description: 32 pages
Automated Capillary Electrophoresis System for Fast Single-Cell Analysis
Creators: name: Allbritton, Nancy L.
name: Dickinson, Alexandra J.
name: Armistead, Paul M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Capillary electrophoresis (CE) is a promising technique for single-cell analysis, but its use in biological studies has been limited by low throughput. This paper presents an automated platform employing microfabricated cell traps and a three-channel system for rapid buffer exchange for fast single-cell CE. Cells loaded with fluorescein and Oregon green were analyzed at a throughput of 3.5 cells/min with a resolution of 2.3 ± 0.6 for the fluorescein and Oregon green. Cellular protein kinase B (PKB) activity, as measured by immunofluorescence staining of phospho-PKB, was not altered, suggesting that this stress-activated kinase was not upregulated during the CE experiments and that basal cell physiology was not perturbed prior to cell lysis. The activity of sphingosine kinase (SK), which is often upregulated in cancer, was measured in leukemic cells by loading a sphingosine-fluorescein substrate into cells. Sphingosine fluorescein (SF), sphingosine-1-phosphate fluorescein (S1PF), and a third fluorescent species were identified in single cells. A single-cell throughput of 2.1 cells/min was achieved for 219 total cells. 88% of cells possessed upregulated SK activity, although subpopulations of cells with markedly different SK activity relative to that of the population average were readily identified. This system was capable of stable and reproducible separations of biological compounds in hundreds of adherent and nonadherent cells, enabling measurements of previously uncharacterized biological phenomena.
The Leja method revisited: backward error analysis for the matrix exponential
Creators: name: Caliari, Marco
name: Kandolf, Peter
name: Ostermann, Alexander
name: Rainer, Stefan
Publisher: name: arXiv
Year: 2015
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: G.1.0; G.1.2; G.1.3; G.1.7
subject: 65F60, 65D05, 65F30

description: The Leja method is a polynomial interpolation procedure that can be used to compute matrix functions. In particular, computing the action of the matrix exponential on a given vector is a typical application. This quantity is required, e.g., in exponential integrators. The Leja method essentially depends on three parameters: the scaling parameter, the location of the interpolation points, and the degree of interpolation. We present here a backward error analysis that allows us to determine these three parameters as a function of the prescribed accuracy. Additional aspects that are required for an efficient and reliable implementation are discussed. Numerical examples that illustrate the performance of our Matlab code are included.
Electrokinetically-Driven Transport of DNA through Focused Ion Beam Milled Nanofluidic Channels
Creators: name: Ramsey, J. Michael
name: Menard, Laurent D.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: The electrophoretically-driven transport of double-stranded λ-phage DNA through focused ion beam (FIB) milled nanochannels is described. Nanochannels were fabricated having critical dimensions (width and depth) corresponding to 0.5×, 1×, and 2× the DNA persistence length – or 25 nm, 50 nm, and 100 nm, respectively. The threshold field strength required to drive transport, the threading mobility, and the transport mobility were measured as a function of nanochannel size. As the nanochannel dimensions decreased, the entropic barrier to translocation increased and transport became more constrained. Equilibrium models of confinement provide a framework in which to understand the observed trends, although the dynamic nature of the experiments resulted in significant deviations from theory. It was also demonstrated that the use of dynamic wall coatings for the purpose of electroosmotic flow suppression can have a significant impact on transport dynamics that may obfuscate entropic contributions. The non-intermittent DNA transport through the FIB milled nanochannels demonstrates that they are well suited for use in nanofluidic devices. We expect that an understanding of the dynamic transport properties reported here will facilitate the incorporation of FIB-milled nanochannels in devices for single molecule and ensemble analyses.
Flexible Software Platform for Fast-Scan Cyclic Voltammetry Data Acquisition and Analysis
Creators: name: Bucher, Elizabeth S.
name: Owesson-White, Catarina
name: Keithley, Richard B.
name: McKinney, Collin J.
name: Carroll, Susan
name: Takmakov, Pavel
name: Brooks, Kenneth
name: Wightman, R. Mark
name: Verber, Matthew D.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Over the last several decades, fast-scan cyclic voltammetry (FSCV) has proved to be a valuable analytical tool for the real-time measurement of neurotransmitter dynamics in vitro and in vivo. Indeed, FSCV has found application in a wide variety of disciplines including electrochemistry, neurobiology and behavioral psychology. The maturation of FSCV as an in vivo technique led users to pose increasingly complex questions that require a more sophisticated experimental design. To accommodate recent and future advances in FSCV application, our lab has developed High Definition Cyclic Voltammetry (HDCV). HDCV is an electrochemical software suite, and includes data acquisition and analysis programs. The data collection program delivers greater experimental flexibility and better user feedback through live displays. It supports experiments involving multiple electrodes with customized waveforms. It is compatible with TTL-based systems that are used for monitoring animal behavior and it enables simultaneous recording of electrochemical and electrophysiological data. HDCV analysis streamlines data processing with superior filtering options, seamlessly manages behavioral events, and integrates chemometric processing. Furthermore, analysis is capable of handling single files collected over extended periods of time, allowing the user to consider biological events on both sub-second and multi-minute time scales. Here we describe and demonstrate the utility of HDCV for in vivo experiments.
Kondo enhancement of current induced spin accumulation in a quantum dot
Creators: name: Mantsevich, V. N.
name: Smirnov, D. S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Weak spin-orbit coupling produces very limited current induced spin accumulation in semiconductor nanostructures. We demonstrate a possibility to increase parametrically the spin polarization using the Kondo effect. As a model object we consider a quantum dot side coupled to a quantum wire taking into account the spin dependent electron tunneling from the wire to the dot. Using the nonequilibrium Green's functions, we show that the many body correlations between the quantum dot and the quantum wire can increase the current induced spin accumulation at low temperatures by almost two orders of magnitude for the moderate system parameters. The enhancement is related to the Kondo peak formation in the density of states and the spin instability due to the strong Coulomb interaction. This effect may be useful to electrically manipulate the localized electron spins in quantum dots for their quantum applications.
description: 7+5 pages, 3+1 figures
(100692) Charles Beafield
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
Inaccuracies of Nitric Oxide Measurement Methods in Biological Media
Creators: name: Coneski, Peter N.
name: Hunter, Rebecca A.
name: Storm, Wesley L.
name: Schoenfisch, Mark H.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Despite growing reports on the biological action of nitric oxide (NO) as a function of NO payload, the validity of such work is often questionable due to the manner in which NO is measured and/or the solution composition in which NO is quantified. To highlight the importance of measurement technique for a given sample type, NO produced from a small molecule NO donor (N-diazeniumdiolated l-proline, PROLI/NO) and a NO-releasing xerogel film were quantified in a number of physiological buffers and fluids, cell culture media, and bacterial broth using the Griess assay, a chemiluminescence analyzer, and an amperometric NO sensor. Despite widespread use, the Griess assay proved to be inaccurate for measuring NO in many of the media tested. In contrast, the chemiluminescence analyzer provided superb kinetic information in most buffers, but was impractical for NO analysis in proteinaceous media. The electrochemical NO sensor enabled greater flexibility across the various media with potential for spatial resolution, albeit at lower than expected NO totals versus either the Griess assay or chemiluminescence. The results of this study highlight the importance of measurement strategy for accurate NO analysis and reporting NO-based biological activity.
Isolation and in Vitro Culture of Rare Cancer Stem Cells from Patient-Derived Xenografts of Pancreatic Ductal Adenocarcinoma
Creators: name: Allbritton, Nancy L.
name: Herrera, Gabriela
name: Yeh, Jen Jen
name: Gach, Philip C.
name: Attayek, Peter J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Described is the construction of a large array of releasable microstructures (micropallets) along with screening and isolation protocols for sorting rare, approximately 1 in 10,000, cancer stem cells (CSCs) from a heterogeneous cell population. A 10.1 × 7.1 cm array of micropallets (50 × 50 × 75 μm structures and 25 μm micropallet gap) was fabricated on a large glass substrate, providing an array of approximately 1.3 million releasable microstructures. Image analysis algorithms were developed to permit array screening for identification of fluorescently labeled cells in less than 15 minutes using an epifluorescent wide-field microscope with a computer controlled translational stage. Device operation was tested by culturing HeLa cells transfected with green fluorescent protein (GFP) admixed with wild-type HeLa cells at ratios of 1:104 to 1:106 on the array followed by screening to identify flourescent cells. Micropallets containing cells of interest were then selectively released by a focused laser pulse and collected on a numbered poly(dimethylsiloxane (PDMS) substrate with high viability. A direct comparison of this technology with fluorescence-activated cell sorting (FACS) demonstrated that micropallet arrays offered enhanced post sorting purity (100%), yield (100%) and viability (94 – 100%) for rare cell isolation. As a demonstration of the technology’s value, pancreatic tumor cells from Panc-1 cell lines and patient-derived xenografts were screened for the presence of CD24, CD44 and CD326; surface markers of pancreatic CSCs. Following cell isolation and culture, 63 ± 23% of the isolated Panc-1 cells and 35% of sorted human xenograft cells formed tumor spheroids retaining high expression levels of CD24, CD44 and CD326. The ability to isolate rare cells from relatively small sample sizes will facilitate our understanding of cell biology and the development of new therapeutic strategies.
MICROENCAPSULATED NUTRACEUTICAL PRODUCTS DEVELOPMENT AND MEDICINAL VALUES OF MORINGA STENOPETALA LEAVES EXTRACT
Creators: name: DEBEBE WORKU DADI
Publisher: name: Zenodo
Year: 2019

description: MICROENCAPSULATED NUTRACEUTICAL PRODUCTS

DEVELOPMENT AND MEDICINAL VALUES OF MORINGA 

STENOPETALA LEAVES EXTRACT
Interpolated variational iteration method for initial value problems
Creators: name: Salkuyeh, Davod Khojasteh
name: Tavakoli, Ali
Publisher: name: arXiv
Year: 2015
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 34A34, 65L05

description: In order to solve an initial value problem by the variational iteration method, a sequence of functions is produced which converges to the solution under some suitable conditions. In the nonlinear case, after a few iterations the terms of the sequence become complicated, and therefore, computing a highly accurate solution would be difficult or even impossible. In this paper, for one-dimensional initial value problems, we propose a new approach which is based on approximating each term of the sequence by a piecewise linear function. Moreover, the convergence of the method is proved. Three illustrative examples are given to show the superiority of the proposed method over the classical variational iteration method.
description: 17 pages, 8 figures in Applied Mathematical Modelling, 2016
An argument for psi-ontology in terms of protective measurements
Creators: name: Gao, Shan
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: History and Philosophy of Physics (physics.hist-ph)
subject: FOS: Physical sciences

description: The ontological model framework provides a rigorous approach to address the question of whether the quantum state is ontic or epistemic. When considering only conventional projective measurements, auxiliary assumptions are always needed to prove the reality of the quantum state in the framework. For example, the Pusey-Barrett-Rudolph theorem is based on an additional preparation independence assumption. In this paper, we give a new proof of psi-ontology in terms of protective measurements in the ontological model framework. The proof does not rely on auxiliary assumptions, and also applies to deterministic theories such as the de Broglie-Bohm theory. In addition, we give a simpler argument for psi-ontology beyond the framework, which is only based on protective measurements and a weaker criterion of reality. The argument may be also appealing for those people who favor an anti-realist view of quantum mechanics.
description: 13 pages, no figures. Studies in History and Philosophy of Modern Physics, Available online 17 August 2015
Range-compatible homomorphisms on spaces of symmetric or alternating matrices
Creators: name: Pazzis, Clément de Seguins
Publisher: name: arXiv
Year: 2015
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 15A03, 15A30

description: Let $U$ and $V$ be finite-dimensional vector spaces over an arbitrary field $\mathbb{K}$, and $\mathcal{S}$ be a linear subspace of the space $\mathcal{L}(U,V)$ of all linear maps from $U$ to $V$. A map $F : \mathcal{S} \rightarrow V$ is called range-compatible when it satisfies $F(s) \in \mathrm{im}(s)$ for all $s \in \mathcal{S}$. Among the range-compatible maps are the so-called local ones, that is the maps of the form $s \mapsto s(x)$ for a fixed vector $x$ of $U$. In recent works, we have classified the range-compatible group homomorphisms on $\mathcal{S}$ when the codimension of $\mathcal{S}$ in $\mathcal{L}(U,V)$ is small. In the present article, we study the special case when $\mathcal{S}$ is a linear subspace of the space $S_n(\mathbb{K})$ of all $n$ by $n$ symmetric matrices: we prove that if the codimension of $\mathcal{S}$ in $S_n(\mathbb{K})$ is less than or equal to $n-2$, then every range-compatible homomorphism on $\mathcal{S}$ is local provided that $\mathbb{K}$ does not have characteristic $2$. With the same assumption on the codimension of $\mathcal{S}$, we also classify the range-compatible homomorphisms on $\mathcal{S}$ when $\mathbb{K}$ has characteristic $2$. Finally, we prove that if $\mathcal{S}$ is a linear subspace of the space $A_n(\mathbb{K})$ of all $n$ by $n$ alternating matrices with entries in $\mathbb{K}$, and the codimension of $\mathcal{S}$ is less than or equal to $n-3$, then every range-compatible homomorphism on $\mathcal{S}$ is local.
description: 33 pages
(100693) Charlotte Beafield
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
Aflatoxin Content of Peanut (Arachis hypogaea) in Relation to Shelling and Storage Practices of Ethiopian Farmers
Creators: name: Eshetu Legesse
Publisher: name: Zenodo
Year: 2010

description: Aflatoxin Content of Peanut (Arachis hypogaea) in Relation 

to Shelling and Storage Practices of Ethiopian Farmers
(100694) Charlotte Beafield
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
(100695) William Crofton Beatty
Creators: name: Professions, Victorian
Publisher: name: University of Oxford
Year: 2022
Subjects: subject: 220201 Business and Labour History
subject: FOS: Philosophy, ethics and religion
subject: History
subject: 140203 Economic History
subject: FOS: Economics and business

description: This three-year research project began in January 2014 and investigated whether, during the Victorian period, the professions formed a distinct self-sustaining social group with its own mores and values. The project looked at 16,000 individuals drawn from census data for Alnwick, Brighton, Bristol, Dundee, Greenock, Leeds, Merthyr Tydfil, Morpeth, and Winchester. The research project was funded by the UK Economic & Social Research Council and was based at the Universities of Oxford and Northumbria.
A Compton-thin Solution for the Suzaku X-ray Spectrum of the Seyfert 2 Galaxy Mkn 3
Creators: name: Yaqoob, T.
name: Tatum, M. M.
name: Scholtes, A.
name: Gottlieb, A.
name: Turner, T. J.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Mkn 3 is a Seyfert 2 galaxy that is widely regarded as an exemplary Compton-thick AGN. We study the Suzaku X-ray spectrum using models of the X-ray reprocessor that self-consistently account for the Fe K$α$ fluorescent emission line and the associated Compton-scattered, or reflection, continuum. We find a solution in which the average global column density, $0.234^{+0.012}_{-0.010} \times 10^{24} \ \rm cm^{-2}$, is very different to the line-of-sight column density, $0.902^{+0.012}_{-0.013} \times 10^{24} \ \rm cm^{-2}$. The global column density is $\sim 5$ times smaller than that required for the matter distribution to be Compton-thick. Our model accounts for the profiles of the Fe K$α$ and Fe K$β$ lines, and the Fe K edge remarkably well, with a solar abundance of Fe. The matter distribution could consist of a clumpy medium with a line-of-sight column density higher than the global average. A uniform, spherically-symmetric distribution alone cannot simultaneously produce the correct fluorescent line spectrum and reflection continuum. Previous works on Mkn 3, and other AGN, that assumed a reflection continuum from matter with an infinite column density could therefore lead to erroneous or "puzzling" conclusions if the matter out of the line-of-sight is really Compton-thin. Whereas studies of samples of AGN have generally only probed the line-of-sight column density, with simplistic, one-dimensional models, it is important now to establish the global column densities in AGN. It is the global properties that affect the energy budget in terms of reprocessing of X-rays into infrared emission, and that constrain population synthesis models of the cosmic X-ray background.
description: Accepted by MNRAS, 23 pages, 6 figures, 4 tables
Measurement of Protein Tyrosine Phosphatase Activity in Single Cells by Capillary Electrophoresis
Creators: name: Allbritton, Nancy L.
name: Bair, Eric
name: Phillips, Ryan M.
name: Lawrence, David S.
name: Sims, Christopher E.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: A fluorescent peptide substrate was used to measure dephosphorylation by protein tyrosine phosphatases (PTP) in cell lysates, and single cells and to investigate the effect of environmental toxins on PTP activity in these systems. Dephosphorylation of the substrate by PTPN1 and PTPN2 obeyed Michaelis-Menten kinetics, with KM values of 770 ± 250 nM and 290 ± 54 nM, respectively. Dose-response curves and IC50 values were determined for the inhibition of these two enzymes by the environmental toxins Zn2+ and 1,2-naphthoquinone, as well as pervanadate. In A431 cell lysates, the reporter was a poor substrate for peptidases (degradation rate of 100 ± 8.2 fmol min−1 mg−1) but an excellent substrate for phosphatases (dephosphorylation rate of 1.4 ± 0.3 nmol min−1 mg−1). Zn2+, 1,2-naphthoquinone and pervanadate inhibited dephosphorylation of the reporter in cell lysates with IC50 values of 470 nM, 35 μM, and 100 nM, respectively. Dephosphorylation of the reporter following loading into living single cells occurred at rates of at least 2 pmol min−1 mg−1. When single cells were exposed to 1,2-naphthoquinone (50 μM), Zn2+ (100 μM), and pervandate (1 mM), dephosphorylation was inhibited with median values and first and third quartile values of 41 (Q1 = 0%, Q3 = 96%), 50 (Q1 = 46%, Q3 = 74%), and 53% (Q1 = 36%, Q3 = 77%), respectively, demonstrating both the impact of these toxic exposures on cell signaling and the heterogeneity of response between cells. This approach will provide a valuable tool for the study of PTP dynamics, particularly in small, heterogeneous populations such as human biopsy specimens.
Contribution of domain wall networks to the CMB power spectrum
Creators: name: Lazanu, A.
name: Martins, C. J. A. P.
name: Shellard, E. P. S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We use three domain wall simulations from the radiation era to the late time dark energy domination era based on the PRS algorithm to calculate the energy-momentum tensor components of domain wall networks in an expanding universe. Unequal time correlators in the radiation, matter and cosmological constant epochs are calculated using the scaling regime of each of the simulations. The CMB power spectrum of a network of domain walls is determined. The first ever quantitative constraint for the domain wall surface tension is obtained using a Markov chain Monte Carlo method; an energy scale of domain walls of 0.93 MeV, which is close but below the Zel'dovich bound, is determined.
description: Submitted to Physics Letters B
Z > 7 galaxies with red Spitzer/IRAC [3.6]-[4.5] colors in the full CANDELS data set: the brightest-known galaxies at Z ~ 7-9 and a probable spectroscopic confirmation at Z=7.48
Creators: name: Roberts-Borsani, G. W.
name: Bouwens, R. J.
name: Oesch, P. A.
name: Labbe, I.
name: Smit, R.
name: Illingworth, G. D.
name: van Dokkum, P.
name: Holden, B.
name: Gonzalez, V.
name: Stefanon, M.
name: Holwerda, B.
name: Wilkins, S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We identify 4 unusually bright (H < 25.5) galaxies from HST and Spitzer CANDELS data with probable redshifts z ~ 7-9. These identifications include the brightest-known galaxies to date at z > 7.5. As Y-band observations are not available over the full CANDELS program to perform a standard Lyman-break selection of z > 7 galaxies, we employ an alternate strategy using deep Spitzer/IRAC data. We identify z ~ 7.1 - 9.1 galaxies by selecting z >~ 6 galaxies from the HST CANDELS data that show quite red IRAC [3.6]-[4.5] colors, indicating strong [OIII]+Hbeta lines in the 4.5 micron band. This selection strategy was validated using a modest sample for which we have deep Y-band coverage, and subsequently used to select the brightest z > 7 sources. Applying the IRAC criteria to all HST-selected optical-dropout galaxies over the full ~900 arcmin**2 of the CANDELS survey revealed four unusually bright z ~ 7.1, 7.6, 7.9 and 8.6 candidates. The median [3.6]-[4.5] color of our selected z ~ 7.1-9.1 sample is consistent with rest-frame [OIII]+Hbeta EWs of ~1500A, in the [4.5] band. Keck/MOSFIRE spectroscopy has been independently reported for two of our selected sources, showing Ly-alpha at redshifts of 7.7302+/-0.0006 and 8.683^+0.001_-0.004, respectively. We present similar Keck/MOSFIRE spectroscopy for a third selected galaxy with a probable 4.7sigma Ly-alpha line at z_spec=7.4770+/-0.0008. All three have H-band magnitudes of ~25 mag and are ~0.5 mag more luminous (M(UV) ~ -22.0) than any previously discovered z ~ 8 galaxy, with important implications for the UV LF. Our 3 brightest, highest redshift z > 7 galaxies all lie within the CANDELS EGS field, providing a dramatic illustration of the potential impact of field-to-field variance.
description: 19 pages, 13 figures, 5 tables, accepted for publication in the Astrophysical Journal. Updated to match the version in press and reflect spectroscopic confirmation of the highest redshift candidate in our sample by Zitrin+2015
Microfluidic Amperometric Sensor for Analysis of Nitric Oxide in Whole Blood
Creators: name: Henley, W. Hampton
name: Privett, Benjamin J.
name: Mittal, Rohit
name: McDunn, Jonathan E.
name: Hunter, Rebecca A.
name: Ramsey, J. Michael
name: Schoenfisch, Mark H.
name: Burd, Eileen M.
name: Yoseph, Benyam P.
name: Breed, Elise R.
name: Liang, Zhe
name: Coopersmith, Craig M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Standard photolithographic techniques and a nitric oxide (NO) selective xerogel polymer were utilized to fabricate an amperometric NO microfluidic sensor with low background noise and the ability to analyze NO levels in small sample volumes (~250 μL). The sensor exhibited excellent analytical performance in phosphate buffered saline, including a NO sensitivity of 1.4 pA nM−1, a limit of detection (LOD) of 840 pM, and selectivity over nitrite, ascorbic acid, acetaminophen, uric acid, hydrogen sulfide, ammonium, ammonia, and both protonated and deprotonated peroxynitrite (selectivity coefficients of −5.3, −4.2, −4.0, −5.0, −6.0, −5.8, −3.8, −1.5, and −4.0 respectively). To demonstrate the utility of the microfluidic NO sensor for biomedical analysis, the device was used to monitor changes in blood NO levels during the onset of sepsis in a murine pneumonia model.
Microfluidic Chemical Cytometry of Peptide Degradation in Single Drug-Treated Acute Myeloid Leukemia Cells
Creators: name: Armistead, Paul M.
name: Allbritton, Nancy L.
name: Shah, Pavak K.
name: Kovarik, Michelle L.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: Microfluidic systems show great promise for single-cell analysis, but as these technologies mature their utility must be validated by studies of biologically-relevant processes. An important biomedical application of these systems is characterization of tumor cell heterogeneity. In this work, we used a robust microfluidic platform to explore the heterogeneity of enzyme activity in single cells treated with a chemotherapeutic drug. Using chemical cytometry, we measured peptide degradation in the U937 acute myeloid leukemia (AML) cell line in the presence and absence of the aminopeptidase inhibitor Tosedostat (CHR-2797). Analysis of 99 untreated cells revealed rapid and consistent degradation of the peptide reporter within 20 min of loading. Results from drug-treated cells showed inhibited, but on-going degradation of the reporter. Because the device operates at an average sustained throughput of 37 ± 7 cells/h, we were able to sample cells over the course of this time-dependent degradation. In data from 498 individual drug-treated cells, we found a linear dependence of degradation rate on amount of substrate loaded superimposed upon substantial heterogeneity in peptide processing in response to inhibitor treatment. Importantly, these data demonstrated the potential of microfluidic systems to sample biologically-relevant analytes and time-dependent processes in large numbers of single cells.
Late time behavior of the massive Dirac field in D-dimensional Minkowski spacetime
Creators: name: Lopez-Ortega, A.
name: Rojas-Luis, M. Y.
Publisher: name: arXiv
Year: 2015
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: To extend previous results on the late time behavior of massive fields, for the Dirac field propagating in the D-dimensional Minkowski spacetime we calculate analytically its asymptotic tails. We find that the massive Dirac field has an oscillatory inverse power law tail. The frequency of the oscillations depends on the mass of the field and the power law decay rate depends on the dimension of the spacetime and the mode number of the angular eigenvalues. We also compare with previous results in curved spacetimes.
description: 9 pages, 2 figures