cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Differentiable engulfing and coverings of manifolds
Creators: name: MacLean, Douglas W.
Publisher: name: University of British Columbia
Year: 2011

description: There are now engulfing theorems for topological, piecewise linear, and differentiable manifolds. Differentiable engulfing so far was reduced to piecewise linear engulfing using the J. H. C. Whitehead triangulation of a differentiable manifold and J. R. Munkres' theory of obstructions to the smoothing of piecewise-differentiable homeomorphisms. In the first part of the thesis we observe that the method of proof of M. H. A. Newman's topological engulfing theorem applies, up to a local lemma, simultaneously to all three categories of manifolds. We prove this local lemma in the differentiable case and thus obtain a differentiable engulfing theorem which has a direct proof. Then we solve the problem of the existence of a stretching diffeomorphism between complementary subcomplexes of a simplicial complex in Euclidean space which is crucial for all applications of engulfing. Next we prove a theorem concerning the uniqueness of open differentiable cylinders which is the differentiable analogue of the uniqueness theorem for open cones. A consequence of this theorem is that if M₁ and M₂ are compact differentiable manifolds with diffeomorphic interiors then M₁x R and M₂xR are diffeomorphic, where (R denotes the real line. Another consequence is that if a differentiable manifold is the monotone union of open differentiable cells it is diffeomorphic to Euclidean space. We present several applications of differentiable engulfing which actually hold in all three categories of manifolds. Our methods are such that they apply also to noncompact manifolds. Theorem: [formulae omitted] This theorem has several corollaries. For instance, if M is a k-connected differentiable manifold of dimension n without boundary, k ≤ n - 3 if k>0, and if [formula omitted] then M may be covered by m open differentiable n-cells. Using this result, we give a new and direct proof of the uniqueness of the differentiable structure of Euclidean n-space for n ≥ 5. Finally, we prove a general h-cobordism theorem. Theorem: Let M be a connected differentiable manifold of dimension n, n ≥ 5, with two connected boundary components N₁, and N₂ such that the inclusion of N₁ into M is a homotopy equivalence, i = 1,2. Then there is a diffeomorphism of N₁x(0,oo) onto M - N₂.
General Case Integer Subtraction
Creators: name: Reyes Alova, Chard Aye
Publisher: name: figshare
Year: 2021
Subjects: subject: 10399 Numerical and Computational Mathematics not elsewhere classified
subject: FOS: Mathematics
subject: 80299 Computation Theory and Mathematics not elsewhere classified
subject: FOS: Computer and information sciences
subject: 80202 Applied Discrete Mathematics
subject: Computation Theory and Mathematics
subject: 130208 Mathematics and Numeracy Curriculum and Pedagogy
subject: FOS: Educational sciences

description: Vedic Mathematics is a holistic, coherent, and unified system of Mathematics. Subtraction is one of the fundamental operations of mathematics, and also one of which that pupils see as difficult. But now with the system of Vedic Mathematics, subtraction can be done with a much simpler, easier, and more creative method which can change the way pupils see Subtraction as a fundamental operation in Arithmetic and in the whole of Mathematics. This paper shows the firepower of the sutras All from Nine and the Last from Ten for the General Case Arithmetic Subtraction, and with the help of the sutra Transpose and Apply for the General Case Integer Subtraction.
ANOTASI UNTUK KEPMENDIKBUD NO. 754/P/2020 TENTANG INDIKATOR KINERJA UTAMA PERGURUAN TINGGI NEGERI DAN LEMBAGA LAYANAN PENDIDIKAN TINGGI DI LINGKUNGAN KEMENTERIAN PENDIDIKAN DAN KEBUDAYAAN TAHUN 2O2O
Creators: name: Irawan, Dasapta Erwin
Publisher: name: Zenodo
Year: 2020
Subjects: Kepmendikbud 754 2020
Kepmendikbud tentang kinerja perguruan tinggi dan lembaga layanan
sains terbuka

description: Dokumen ini merupakan berkas PDF Kepmendikbud No. 754/P/2020 yang berisi dua puluh tiga (23) anotasi saya.
A note on restriction theorems for semistable sheaves
Creators: name: Langer, Adrian
Publisher: name: arXiv
Year: 2009
Subjects: subject: Algebraic Geometry (math.AG)
subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: 14J60, 13A35, 13D02

description: We prove a new restriction theorem for semistable sheaves on varieties in all characteristics strengthening previous results. We also prove restriction theorem for strong semistability for varieties with some non-negativity constrains on the cotangent bundle (e.g., most of Fano and Calabi-Yau varieties).
description: 12 pages, to appear in Mathematical Research Letters, appendix contained serious error pointed out by Trivedi and it is removed in this version
Black Holes in Gravity with Conformal Anomaly and Logarithmic Term in Black Hole Entropy
Creators: name: Cai, Rong-Gen
name: Cao, Li-Ming
name: Ohta, Nobuyoshi
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We present a class of exact analytic and static, spherically symmetric black hole solutions in the semi-classical Einstein equations with Weyl anomaly. The solutions have two branches, one is asymptotically flat and the other asymptotically de Sitter. We study thermodynamic properties of the black hole solutions and find that there exists a logarithmic correction to the well-known Bekenstein-Hawking area entropy. The logarithmic term might come from non-local terms in the effective action of gravity theories. The appearance of the logarithmic term in the gravity side is quite important in the sense that with this term one is able to compare black hole entropy up to the subleading order, in the gravity side and in the microscopic statistical interpretation side.
description: Revtex, 10 pages. v2: minor changes and to appear in JHEP
Weak bimonads and weak Hopf monads
Creators: name: Böhm, Gabriella
name: Lack, Stephen
name: Street, Ross
Publisher: name: arXiv
Year: 2010
Subjects: subject: Category Theory (math.CT)
subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: 18D10, 18C15, 16T10, 16T05

description: We define a weak bimonad as a monad T on a monoidal category M with the property that the Eilenberg-Moore category M^T is monoidal and the forgetful functor from M^T to M is separable Frobenius. Whenever M is also Cauchy complete, a simple set of axioms is provided, that characterizes the monoidal structure of M^T as a weak lifting of the monoidal structure of M . The relation to bimonads, and the relation to weak bimonoids in a braided monoidal category are revealed. We also discuss antipodes, obtaining the notion of weak Hopf monad.
description: 29 pages; version 2 minor corrections and added references, also added remark 4.3; title changed from "Weak bimonads" to "Weak bimonads and weak Hopf monads"; to appear in Journal of Algebra
Mass estimate of the XTE J1650-500 black hole from the Extended Orbital Resonance Model for high-frequency QPOs
Creators: name: Slany, Petr
name: Stuchlik, Zdenek
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: XTE J1650-500 is a Galactic black-hole binary system for which at least one high-frequency QPO at 250Hz was reported. Moreover there are indications that the system harbours a near-extreme Kerr black-hole with the spin near 0.998 and mass M<7.3M_sun. Recently it was discovered that the orbital 3-velocity of Keplerian (geodesical) discs orbiting Kerr black holes with the spin a>0.9953, being analyzed in the locally non-rotating frames, reveals a hump near the marginally stable orbit. Further it was suggested that the hump could excite the epicyclic motion of particles near the ISCO with frequencies typical for high-frequency QPOs. Characteristic frequency of the hump-induced oscillations was defined as the maximal positive rate of change of the LNRF-related orbital velocity with the proper radial distance. If the characteristic "humpy frequency" and the radial epicyclic frequency are commensurable, strong resonant phenomena are expected. For the Kerr black hole with the spin a=0.9982 the "humpy frequency" and the radial epicyclic frequency are in ratio 1:3. Identifying the radial epicyclic frequency with the observed 250Hz QPO, we get the mass of the black hole in XTE J1650-500 near 5.1M_sun.
description: 5 pages; accepted for publication in A&A
Nonlinear stability analysis of the Emden-Fowler equation
Creators: name: Boehmer, Christian G.
name: Harko, Tiberiu
Publisher: name: arXiv
Year: 2009
Subjects: subject: Mathematical Physics (math-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences
subject: 34D20, 35B35, 37C75

description: In this paper we qualitatively study radial solutions of the semilinear elliptic equation $Δu + u^n = 0$ with $u(0)=1$ and $u'(0)=0$ on the positive real line, called the Emden-Fowler or Lane-Emden equation. This equation is of great importance in Newtonian astrophysics and the constant $n$ is called the polytropic index. By introducing a set of new variables, the Emden-Fowler equation can be written as an autonomous system of two ordinary differential equations which can be analyzed using linear and nonlinear stability analysis. We perform the study of stability by using linear stability analysis, the Jacobi stability analysis (Kosambi-Cartan-Chern theory) and the Lyapunov function method. Depending on the values of $n$ these different methods yield different results. We identify a parameter range for $n$ where all three methods imply stability.
description: 12 pages; new reference added; 3 new references added; fully revised version
Archaeological Investigations at the Stephen and Harriet Myers and Thomas Elkins Properties, Albany, NY: 2017 and 2018 Seasons
Creators: name: Masson, Marilyn
name: Lucas, Michael T.
name: Kirk, Matthew
Publisher: name: unpublished report
Year: 2021
Subjects: subject: Northeast
valueUri: https://core.tdar.org/browse/geographic-keyword/16157/northeast
subject: Albany, NY
valueUri: https://core.tdar.org/browse/geographic-keyword/85478/albany-ny
subject: 19th Century, Historical
valueUri: https://core.tdar.org/browse/temporal-keyword/7097/19th-century-historical
subject: African-American Slaves
valueUri: https://core.tdar.org/browse/culture-keyword/4768/african-american-slaves
subject: Historic
valueUri: https://core.tdar.org/browse/culture-keyword/25/historic
subject: African American
valueUri: https://core.tdar.org/browse/culture-keyword/26/african-american
subject: Domestic Structure or Architectural Complex
valueUri: https://core.tdar.org/browse/site-type/251/domestic-structure-or-architectural-complex
subject: Shell
valueUri: https://core.tdar.org/browse/material-type/14/shell
subject: Textile
valueUri: https://core.tdar.org/browse/material-type/16/textile
subject: Ceramic
valueUri: https://core.tdar.org/browse/material-type/1/ceramic
subject: Chipped Stone
valueUri: https://core.tdar.org/browse/material-type/2/chipped-stone
subject: Hide
valueUri: https://core.tdar.org/browse/material-type/18/hide
subject: Fauna
valueUri: https://core.tdar.org/browse/material-type/4/fauna
subject: Ground Stone
valueUri: https://core.tdar.org/browse/material-type/7/ground-stone
subject: Metal
valueUri: https://core.tdar.org/browse/material-type/11/metal
subject: Underground Railroad
valueUri: https://core.tdar.org/browse/other-keyword/10701/underground-railroad
subject: Archaeological Overview
valueUri: https://core.tdar.org/browse/investigation-type/1/archaeological-overview

description: Mid-nineteenth century archaeological investigation of stratigraphy, features, and artifacts associated with the Myers and Elkins residences, homes in the 1850s to African American abolitionists (and with later nineteenth century materials analyzed as well).
title: MISPRONUNCIATION DETECTION AND DIAGNOSIS IN MANDARIN ACCENTED ENGLISH SPEECH
Creators: name: Khanal, Subash
Publisher: name: University of Kentucky Libraries
Year: 2020
Subjects: subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This work presents the development, implementation, and evaluation of a Mispronunciation Detection and Diagnosis (MDD) system, with application to pronunciation evaluation of Mandarin-accented English speech. A comprehensive detection and diagnosis of errors in the Electromagnetic Articulography corpus of Mandarin-Accented English (EMA-MAE) was performed by using the expert phonetic transcripts and an Automatic Speech Recognition (ASR) system. Articulatory features derived from the parallel kinematic data available in the EMA-MAE corpus were used to identify the most significant articulatory error patterns seen in L2 speakers during common mispronunciations. Using both acoustic and articulatory information, an ASR based Mispronunciation Detection and Diagnosis (MDD) system was built and evaluated across different feature combinations and Deep Neural Network (DNN) architectures. The MDD system captured mispronunciation errors with a detection accuracy of 82.4%, a diagnostic accuracy of 75.8% and a false rejection rate of 17.2%. The results demonstrate the advantage of using articulatory features in revealing the significant contributors of mispronunciation as well as improving the performance of MDD systems.
description: © 2020 Subash Khanal
A nuclear magnetic resonance based approach to accurate functional annotation of putative enzymes in the methanogen Methanosarcina acetivorans
Creators: name: Chen, Yihong
name: Apolinario, Ethel
name: Brachova, Libuse
name: Kelman, Zvi
name: Li, Zhuo
name: Nikolau, Basil J
name: Showman, Lucas
name: Sowers, Kevin
name: Orban, John
Publisher: name: Springer Nature
Year: 2011
Subjects: Nuclear Magnetic Resonance
Nuclear Magnetic Resonance Experiment
Functional Assignment
Nuclear Magnetic Resonance Sample
Putative Enzyme

description: Correct annotation of function is essential if one is to take full advantage of the vast amounts of genomic sequence data. The accuracy of sequence-based functional annotations is often variable, particularly if the sequence homology to a known function is low. Indeed recent work has shown that even proteins with very high sequence identity can have different folds and functions, and therefore caution is needed in assigning functions by sequence homology in the absence of experimental validation. Experimental methods are therefore needed to efficiently evaluate annotations in a way that complements current high throughput technologies. Here, we describe the use of nuclear magnetic resonance (NMR)-based ligand screening as a tool for testing functional assignments of putative enzymes that may be of variable reliability. The target genes for this study are putative enzymes from the methanogenic archaeon Methanosarcina acetivorans (MA) that have been selected after manual genome re-annotation and demonstrate detectable in vivo expression at the level of the transcriptome. The experimental approach begins with heterologous E. coli expression and purification of individual MA gene products. An NMR-based ligand screen of the purified protein then identifies possible substrates or products from a library of candidate compounds chosen from the putative pathway and other related pathways. These data are used to determine if the current sequence-based annotation is likely to be correct. For a number of case studies, additional experiments (such as in vivo genetic complementation) were performed to determine function so that the reliability of the NMR screen could be independently assessed. In all examples studied, the NMR screen was indicative of whether the functional annotation was correct. Thus, the case studies described demonstrate that NMR-based ligand screening is an effective and rapid tool for confirming or negating the annotated gene function of putative enzymes. In particular, no protein-specific assay needs to be developed, which makes the approach broadly applicable for validating putative functions using an automated pipeline strategy.
Superinjective Simplicial Maps of the Complexes of Curves on Nonorientable Surfaces
Creators: name: Irmak, Elmas
Publisher: name: arXiv
Year: 2009
Subjects: subject: Geometric Topology (math.GT)
subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 57M99, 20F38

description: We prove that each superinjective simplicial map of the complex of curves of a compact, connected, nonorientable surface is induced by a homeomorphism of the surface, if $(g, n) \in \{(1, 0), (1, 1), (2, 0), (2, 1), (3, 0)\}$ or $g + n \geq 5$, where $g$ is the genus of the surface and $n$ is the number of the boundary components.
description: In response to comments from the referee, the paper was shortened and reorganized. A minor mistake pointed out by the referee was also corrected
On the S-fundamental group scheme
Creators: name: Langer, Adrian
Publisher: name: arXiv
Year: 2009
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14J60, 14F35

description: We introduce a new fundamental group scheme for varieties defined over an algebraically closed field of positive characteristic and we use it to study generalization of some of C. Simpson's results to positive characteristic. We also study the properties of this group and we prove Lefschetz type theorems.
description: 37 pages; final version will appear in Ann. Inst. Fourier 61 (2011)
Galaxy Counts on the CMB Cold Spot
Creators: name: Granett, Benjamin R.
name: Szapudi, István
name: Neyrinck, Mark C.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The Cold Spot on the Cosmic Microwave Background could arise due to a supervoid at low redshift through the integrated Sachs-Wolfe effect. We imaged the region with MegaCam on the Canada-France-Hawai'i Telescope and present galaxy counts in photometric redshift bins. We rule out the existence of a 100Mpc radius spherical supervoid with underdensity delta=-0.3 at 0.5
description: 9 pages. Minor updates to match the article accepted to ApJ.
Complete Columbian mammoth mitogenome suggests interbreeding with woolly mammoths
Creators: name: Enk, Jacob
name: Devault, Alison
name: Debruyne, Regis
name: King, Christine E
name: Treangen, Todd
name: O'Rourke, Dennis
name: Salzberg, Steven L
name: Fisher, Daniel
name: MacPhee, Ross
name: Poinar, Hendrik
Publisher: name: Springer Nature
Year: 2011
Subjects: Coverage Depth
Complete Mitochondrial Genome
Incomplete Lineage Sorting
Much Recent Common Ancestor
Asiatic Elephant

description: Late Pleistocene North America hosted at least two divergent and ecologically distinct species of mammoth: the periglacial woolly mammoth (Mammuthus primigenius) and the subglacial Columbian mammoth (Mammuthus columbi). To date, mammoth genetic research has been entirely restricted to woolly mammoths, rendering their genetic evolution difficult to contextualize within broader Pleistocene paleoecology and biogeography. Here, we take an interspecific approach to clarifying mammoth phylogeny by targeting Columbian mammoth remains for mitogenomic sequencing. We sequenced the first complete mitochondrial genome of a classic Columbian mammoth, as well as the first complete mitochondrial genome of a North American woolly mammoth. Somewhat contrary to conventional paleontological models, which posit that the two species were highly divergent, the M. columbi mitogenome we obtained falls securely within a subclade of endemic North American M. primigenius. Though limited, our data suggest that the two species interbred at some point in their evolutionary histories. One potential explanation is that woolly mammoth haplotypes entered Columbian mammoth populations via introgression at subglacial ecotones, a scenario with compelling parallels in extant elephants and consistent with certain regional paleontological observations. This highlights the need for multi-genomic data to sufficiently characterize mammoth evolutionary history. Our results demonstrate that the use of next-generation sequencing technologies holds promise in obtaining such data, even from non-cave, non-permafrost Pleistocene depositional contexts.
Adiabatic Markovian Dynamics
Creators: name: Oreshkov, Ognyan
name: Calsamiglia, John
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose a theory of adiabaticity in quantum Markovian dynamics based on a decomposition of the Hilbert space induced by the asymptotic behavior of the Lindblad semigroup. A central idea of our approach is that the natural generalization of the concept of eigenspace of the Hamiltonian in the case of Markovian dynamics is a noiseless subsystem with a minimal noisy cofactor. Unlike previous attempts to define adiabaticity for open systems, our approach deals exclusively with physical entities and provides a simple, intuitive picture at the underlying Hilbert-space level, linking the notion of adiabaticity to the theory of noiseless subsystems. As an application of our theory, we propose a framework for decoherence-assisted computation in noiseless codes under general Markovian noise. We also formulate a dissipation-driven approach to holonomic computation based on adiabatic dragging of subsystems that is generally not achievable by non-dissipative means.
description: 4+3 pages
Additional file 2 of Tumor size as a significant prognostic factor in T1 gastric cancer: a Surveillance, Epidemiology, and End Results (SEER) database analysis
Creators: name: Xiao, Xueyan
name: Gao, Beibei
name: Pang, Suya
name: Wang, Zeyu
name: Jiang, Weiwei
name: Wang, Weijun
name: Lin, Rong
Publisher: name: figshare
Year: 2023
Subjects: subject: Medicine
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Cancer

description: Additional file 2: Supplementary table 1. Univariate and Multivariate analysis of prognostic factors affecting OS.
Complete WKB asymptotics of high frequency vibrations in a stiff problem
Creators: name: Babych, N.
name: Golovaty, Yu.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Spectral Theory (math.SP)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 34E20; 74K10

description: Asymptotic behaviour of eigenvalues and eigenfunctions of a stiff problem is described in the case of the fourth-order ordinary differential operator. Considering the stiffness coefficient that depends on a small parameter epsilon and vanishes as epsilon tends to zero on a subinterval, we prove the existence of low and high frequency resonance vibrations. The low frequency vibrations admit the power series expansions on epsilon but this method is not applicable to the description of high frequency vibrations. However, the nonclassical asymptotics on epsilon of the high frequency vibrations were constructed using the WKB method.
description: Published in 2001, English is improved in 2008. 15 pages, 2 figures
The evolution of barriers to exploitation: Sometimes the Red Queen can take a break.
Creators: name: Goodman, Jonathan R
name: Ewald, Paul W
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Coevolution
Exploitation
Evolutionary Ecology
Evolutionary Medicine
Red Queen
Barrier Theory

description: We propose a general barrier theory as an evolutionary framework for understanding coevolutionary effects of conflicts of interest in natural and human systems. It is generalized from the barrier theory of cancer, which describes how cancer develops through the evasion of mechanisms, that block unregulated cellular reproduction and survival. Barriers are naturally evolved or artificially implemented mechanisms for blocking exploitation; restraints are mechanisms that impede but do not block exploitation. When conflicts of interest arise, selection will favor exploiters that are capable of overcoming barriers and restraints. When barriers are in place, they halt, at least temporarily, coevolutionary arms races (the Red Queen can stop running). Barriers occur in a broad spectrum of interactions characterized by conflicts of interest: barriers to cellular survival (apoptosis) and reproduction (cell cycle arrest) may block a virus from replicating its genome through reproduction of its host cell. Vaccines may completely protect against targeted pathogens. A plant may escape herbivory by evolving defensive chemicals that block herbivory. Obligate mutualisms may evolve when barriers to horizontal transmission favor symbionts that increasingly lose mechanisms that contribute to horizontal transmission. Here, we show how the barrier theory applies across a spectrum of natural and social systems.
Mean-Field Gauge Interactions in Five Dimensions I. The Torus
Creators: name: Irges, Nikos
name: Knechtli, Francesco
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the lattice regularization of a five dimensional SU(2) gauge theory with periodic boundary conditions. We determine a consistent mean-field background and perform computations of various observables originating from fluctuations around this background. Our aim is to extract the properties of the system in regimes of its phase diagram where it seems to be in a dimensionally reduced state. Within the mean-field theory we establish the existence of a second order phase transition at finite value of the gauge coupling for anisotropy parameter less than one, where there is evidence for dimensional reduction.
description: 53 pages, 21 figures. Discussion of results improved, figures and appendix added. Version accepted for publication in Nucl. Phys. B. Typos and a physically inconsequential mistake in the gauge fixing corrected
Accelerating Reaction Rates of Biomolecules by Using Shear Stress in Artificial Capillary Systems.
Creators: name: Hakala, Tuuli A
name: Yates, Emma V
name: Challa, Pavan K
name: Toprakcioglu, Zenon
name: Nadendla, Karthik
name: Matak-Vinkovic, Dijana
name: Dobson, Christopher M
name: Martínez, Rodrigo
name: Corzana, Francisco
name: Knowles, Tuomas P J
name: Bernardes, Gonçalo J L
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021

description: Funder: Frances and Augustus Newman Foundation
description: Funder: Emmanuel College, University of Cambridge
description: Funder: Biotechnology and Biological Sciences Research Council
description: Funder: Centre for Misfolding Diseases, University of Cambridge
description: Funder: Wellcome Trust
description: Biomimetics is a design principle within chemistry, biology, and engineering, but chemistry biomimetic approaches have been generally limited to emulating nature's chemical toolkit while emulation of nature's physical toolkit has remained largely unexplored. To begin to explore this, we designed biophysically mimetic microfluidic reactors with characteristic length scales and shear stresses observed within capillaries. We modeled the effect of shear with molecular dynamics studies and showed that this induces specific normally buried residues to become solvent accessible. We then showed using kinetics experiments that rates of reaction of these specific residues in fact increase in a shear-dependent fashion. We applied our results in the creation of a new microfluidic approach for the multidimensional study of cysteine biomarkers. Finally, we used our approach to establish dissociation of the therapeutic antibody trastuzumab in a reducing environment. Our results have implications for the efficacy of existing therapeutic antibodies in blood plasma as well as suggesting in general that biophysically mimetic chemistry is exploited in biology and should be explored as a research area.
Transmembrane signal transduction by cofactor transport.
Creators: name: Kocsis, Istvan
name: Ding, Yudi
name: Williams, Nicholas H
name: Hunter, Christopher A
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021

description: Information processing and cell signalling in biological systems relies on passing chemical signals across lipid bilayer membranes, but examples of synthetic systems that can achieve this process are rare. A synthetic transducer has been developed that triggers catalytic hydrolysis of an ester substrate inside lipid vesicles in response to addition of metal ions to the external vesicle solution. The output signal generated in the internal compartment of the vesicles is produced by binding of a metal ion cofactor to a head group on the transducer to form a catalytically competent complex. The mechanism of signal transduction is based on transport of the metal ion cofactor across the bilayer by the transducer, and the system can be reversibly switched between on and off states by adding cadmium(ii) and ethylene diamine tetracarboxylic acid input signals respectively. The transducer is also equipped with a hydrazide moiety, which allows modulation of activity through covalent conjugation with aldehydes. Conjugation with a sugar derivative abolished activity, because the resulting hydrazone is too polar to cross the bilayer, whereas conjugation with a pyridine derivative increased activity. Coupling transport with catalysis provides a straightforward mechanism for generating complex systems using simple components.
Matrices with linear and circular spectra
Creators: name: Chang, Luang-Hung
Publisher: name: University of British Columbia
Year: 2011

description: Much is known about the eigenvalues of some special types of matrices. For example, the eigenvalues of a hermitian or skew-hermitian matrix lie on a line while those of a unitary matrix lie on a circle; their spectra are "linear" or "circular". This suggests the question: What matrices have this property? Or, more generally, what matrices have their eigenvalues on plane curves of a simple kind? Is it possible to recognize such matrices by inspection? In this thesis, we make a small start on these problems, exploring some matrices whose eigenvalues lie on one or more lines, or on one or more circles.
Polynomial constants of motion for Calogero-type systems in three dimensions
Creators: name: Chanu, Claudia
name: Degiovanni, Luca
name: Rastelli, Giovanni
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: We give an explicit and concise formula for higher-degree polynomial first integrals of a family of Calogero-type Hamiltonian systems in dimension three. These first integrals, together with the already known ones, prove the maximal superintegrability of the systems.
description: A small flaw in the proof of Theorem 3 has been amended. Some remarks about dihedral symmetries and superintegrability have been added
SUSY and Higgs Signatures Implied by Cancellations in $b\to sγ$
Creators: name: Chen, Ning
name: Feldman, Daniel
name: Liu, Zuowei
name: Nath, Pran
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Recent re-evaluations of the Standard Model (SM) contribution to ${\mathcal Br(b\to sγ)$ hint at a positive correction from new physics. Since a charged Higgs boson exchange always gives a positive contribution to this branching ratio, the constraint points to the possibility of a relatively light charged Higgs. It is found that under the HFAG constraints and with re-evaluated SM results large cancellations between the charged Higgs and the chargino contributions in supersymmetric models occur. Such cancellations then correlate the charged Higgs and the chargino masses often implying both are light. Inclusion of the more recent evaluation of $g_μ-2$ is also considered. The combined constraints imply the existence of several light sparticles. Signatures arising from these light sparticles are investigated and the analysis indicates the possibility of their early discovery at the LHC in a significant part of the parameter space. We also show that for certain restricted regions of the parameter space, such as for very large $\tanβ$ under the $1σ$ HFAG constraints, the signatures from Higgs production supersede those from sparticle production and may become the primary signatures for the discovery of supersymmetry.
description: Published version. 17 pages, 11 figures. One reference added.
Excess dissipation in a single-electron box: The Sisyphus resistance
Creators: name: Persson, F.
name: Wilson, C. M.
name: Sandberg, M.
name: Johansson, G.
name: Delsing, P.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We present measurements of the ac response of a single-electron box (SEB). We apply an rf signal with a frequency larger than the tunneling rate and drive the system out of equilibrium. We observe much more dissipation in the SEB then one would expect from a simple circuit model. We can explain this in terms of a mechanism that we call the Sisyphus resistance. The Sisyphus resistance has a strong gate dependence which can be used for electrometery applications.
description: 5 pages, 3 figures
Spherical means in annular regions in the $n$-dimensional real hyperbolic spaces
Creators: name: Rawat, Rama
name: Srivastava, R. K.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 30F45, 33C55, 43A85

description: Let $Z_{r,R}$ be the class of all continuous functions $f$ on the annulus $\Ann(r,R)$ in the real hyperbolic space $\mathbb B^n$ with spherical means $M_sf(x)=0$, whenever $s>0$ and $x\in \mathbb B^n$ are such that the sphere $S_s(x)\subset \Ann(r, R) $ and $B_r(o)\subseteq B_s(x).$ In this article, we give a characterization for functions in $Z_{r,R}$. In the case $R=\infty$, this result gives a new proof of Helgason's support theorem for spherical means in the real hyperbolic spaces.
description: published: Proc. Indian. Acad. Sci., 121 (2011), No.3, 311-325
Phase space representation of quantum dynamics
Creators: name: Polkovnikov, Anatoli
Publisher: name: arXiv
Year: 2009
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Gases (cond-mat.quant-gas)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We discuss a phase space representation of quantum dynamics of systems with many degrees of freedom. This representation is based on a perturbative expansion in quantum fluctuations around one of the classical limits. We explicitly analyze expansions around three such limits: (i) corpuscular or Newtonian limit in the coordinate-momentum representation, (ii) wave or Gross-Pitaevskii limit for interacting bosons in the coherent state representation, and (iii) Bloch limit for the spin systems. We discuss both the semiclassical (truncated Wigner) approximation and further quantum corrections appearing in the form of either stochastic quantum jumps along the classical trajectories or the nonlinear response to such jumps. We also discuss how quantum jumps naturally emerge in the analysis of non-equal time correlation functions. This representation of quantum dynamics is closely related to the phase space methods based on the Wigner-Weyl quantization and to the Keldysh technique. We show how such concepts as the Wigner function, Weyl symbol, Moyal product, Bopp operators, and others automatically emerge from the Feynmann's path integral representation of the evolution in the Heisenberg representation. We illustrate the applicability of this expansion with various examples mostly in the context of cold atom systems including sine-Gordon model, one- and two-dimensional Bose Hubbard model, Dicke model and others.
description: 92 pages, typos corrected, published version
Numerical Results for Spin Glass Ground States on Bethe Lattices: Gaussian Bonds
Creators: name: Boettcher, S.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The average ground state energies for spin glasses on Bethe lattices of connectivities r=3,...,15 are studied numerically for a Gaussian bond distribution. The Extremal Optimization heuristic is employed which provides high-quality approximations to ground states. The energies obtained from extrapolation to the thermodynamic limit smoothly approach the ground-state energy of the Sherrington-Kirkpatrick model for r->\infty. Consistently for all values of r in this study, finite-size corrections are found to decay approximately with ~N^{-4/5}. The possibility of ~N^{-2/3} corrections, found previously for Bethe lattices with a bimodal +-J bond distribution and also for the Sherrington-Kirkpatrick model, are constrained to the additional assumption of very specific higher-order terms. Instance-to-instance fluctuations in the ground state energy appear to be asymmetric up to the limit of the accuracy of our heuristic. The data analysis provides insights into the origin of trivial fluctuations when using continuous bonds and/or sparse networks.
description: RevTex4, 9 pages, 15 eps-figs included. More extensive analysis of finite-size corrections; final version. For related information, see http://www.physics.emory.edu/faculty/boettcher/
Contact process on a Voronoi triangulation
Creators: name: de Oliveira, Marcelo M.
name: Alves, S. G.
name: Ferreira, S. C.
name: Dickman, Ronald
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We study the continuous absorbing-state phase transition in the contact process on the Voronoi-Delaunay lattice. The Voronoi construction is a natural way to introduce quenched coordination disorder in lattice models. We simulate the disordered system using the quasistationary simulation method and determine its critical exponents and moment ratios. Our results suggest that the critical behavior of the disordered system is unchanged with respect to that on a regular lattice, i.e., that of directed percolation.
The Ape That Lived to Tell the Tale. The Evolution of the Art of Storytelling and Its Relationship to Mental Time Travel and Theory of Mind
Creators: name: Garcia-Pelegrin, Elias
name: Wilkins, Clive
name: Clayton, Nicola S.
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: subject: Psychology
subject: FOS: Psychology
subject: art
subject: evolution
subject: theory of mind
subject: mental time travel
subject: stories

description: Engaging in the art of creating and telling stories is a defining behaviour of humankind. Humans have been sharing stories with each other, with and without words, since the dawn of recorded history, but the cognitive foundations of the behaviour can be traced deeper into our past. The emergence of stories can be strongly linked to Mental Time Travel (the ability to recall the past and imagine the future) and plays a key role in our ability to communicate past, present and future scenarios with other individuals, within and beyond our lifetimes. Stories are products engraved within the concept of time, constructed to elucidate the past experiences of the self, but designed with the future in mind, thus imparting lessons of such experiences to the receiver. By being privy to the experiences of others, humans can imagine themselves in a similar position to the protagonist of the story, thus mentally learning from an experience they might have never encountered other than in the mind's eye. Evolutionary Psychology investigates how the engagement in artistic endeavours by our ancestors in the Pleistocene granted them an advantage when confronted with obstacles that challenged their survival or reproductive fitness and questions whether art is an adaptation of the human mind or a spandrel of other cognitive adaptations. However, little attention has been placed on the cognitive abilities that might have been imperative for the development of art. Here, we examine the relationship between art, storytelling, Mental Time Travel and Theory of Mind (i.e., the ability to attribute mental states to others). We suggest that Mental Time Travel played a key role in the development of storytelling because through stories, humans can fundamentally transcend their present condition, by being able to imagine different times, separate realities, and place themselves and others anywhere within the time space continuum. We argue that the development of a Theory of Mind also sparked storytelling practises in humans as a method of diffusing the past experiences of the self to others whilst enabling the receiver to dissociate between the past experiences of others and their own, and to understand them as lessons for a possible future. We propose that when artistic products rely on storytelling in form and function, they ought to be considered separate from other forms of art whose appreciation capitalise on our aesthetic preferences.
The Casimir force between parallel plates in Randall-Sundrum I model
Creators: name: Cheng, Hongbo
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The Casimir effect for parallel plates within the frame of five-dimensional Randall-Sundrum model with two branes is reexamined. We argue that the nature of Casimir force is repulsive if the distance between the plates is not extremely tiny, which is not consistent with the experimental phenomena. We also point out that the estimation of the separation between the two branes, by means of Casimir effect for two-parallel-plate system, is not feasible, in contrast to another recent study.
description: 10 pages, 1 figure
The Contextual Essentiality of Mitochondrial Genes in Cancer
Creators: name: Thomas, Luke W.
name: Ashcroft, Margaret
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Cell and Developmental Biology
mitochondria
essentiality
metabolism
viability
signaling

description: Mitochondria are key organelles in eukaryotic evolution that perform crucial roles as metabolic and cellular signaling hubs. Mitochondrial function and dysfunction are associated with a range of diseases, including cancer. Mitochondria support cancer cell proliferation through biosynthetic reactions and their role in signaling, and can also promote tumorigenesis via processes such as the production of reactive oxygen species (ROS). The advent of (nuclear) genome-wide CRISPR-Cas9 deletion screens has provided gene-level resolution of the requirement of nuclear-encoded mitochondrial genes (NEMGs) for cancer cell viability (essentiality). More recently, it has become apparent that the essentiality of NEMGs is highly dependent on the cancer cell context. In particular, key tumor microenvironmental factors such as hypoxia, and changes in nutrient (e.g., glucose) availability, significantly influence the essentiality of NEMGs. In this mini-review we will discuss recent advances in our understanding of the contribution of NEMGs to cancer from CRISPR-Cas9 deletion screens, and discuss emerging concepts surrounding the context-dependent nature of mitochondrial gene essentiality.
Percepção da qualidade do conteúdo de um curso a distância em Ciências da Saúde no Brasil
Creators: name: Silva, André Ribeiro Da
name: Peixoto, Henry Maia
name: Linconl Agudo Oliveira Benito
name: Denismar Borges De Miranda
name: Souza, Silvia Emanoella Silva Martins De
name: Jônatas De França Barros
Publisher: name: Zenodo
Year: 2015

description: Os cursos a distância (EaD) exigem muitos investimentos (preparação de pessoal, infra -estrutura tecnológica, produção de materiais didáticos, sistemas de comunicação, monitoramento e gestão, implantação de polos descentralizados, logística de manutenção e de distribuição de produtos, entre outros (Ministério da Educação, 2003).

O objetivo deste estudo foi descrever a percepção dos alunos (do 2ª semestre de 2014 do curso de Educação Física da Universidade de Brasília) entre o conteúdo proposto e os objetivos das disciplinas do referido curso, através de um questionário online (GoogleDocs), onde participaram 80 alunos do estudo.

Numa escala de 1 a 10, onde 1 é péssimo e 10 excelente, representando a qualidade das disciplinas que foram ministradas, 90% dos entrevistados demostraram bom a excelente e 10% acharam ruim a péssimo a relação da ligação do conteúdo proposto com os objetivos das disciplinas e 93,75% bom a excelente e 6,25% ruim a péssimo a ligação entre os objetivos da disciplina e os seus objetivos pessoais.

Outros estudos devem ser realizados com disciplinas separadas, pelas suas especificidades diferenciadas. O governo do Brasil em 2003 criou um referencial de qualidade para Cursos a Distância, sem poder de lei, mas com referenciais que orienta alunos, professores, técnicos e gestores na busca por maior qualidade. Será que todos envolvidos na EaD tem conhecimento deste documento?
Quantum theory of surface plasmon polariton scattering
Creators: name: Ballester, D.
name: Tame, M. S.
name: Kim, M. S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We introduce the quantum mechanical formalism for treating surface plasmon polariton scattering at an interface. Our developed theory - which is fundamentally different from the analogous photonic scenario - is used to investigate the possibility of plasmonic beamsplitters at the quantum level. Remarkably, we find that a wide-range of splitting ratios can be reached. As an application, we characterize a 50:50 plasmonic beamsplitter and investigate first-order quantum interference of surface plasmon polaritons. The results of this theoretical study show that surface plasmon beamsplitters are able to reliably and efficiently operate in the quantum domain.
description: 16 pages, 7 figures, RevTeX4
Detectable Abundance of Cyanoacetylene (HC 3 N) Predicted on Reduced Nitrogen-rich Super-Earth Atmospheres
Creators: name: Rimmer, Paul B.
name: Majumdar, Liton
name: Priyadarshi, Akshay
name: Wright, Sam
name: Yurchenko, S. N.
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021

description: Abstract: We predict that cyanoacetylene (HC3N) is produced photochemically in the atmosphere of GJ 1132 b in abundances detectable by the James Webb Space Telescope (JWST), assuming that the atmosphere is hydrogen dominated and rich in molecular nitrogen (N2), methane (CH4), and hydrogen cyanide (HCN), as described by Swain et al. First, we construct line lists and cross sections for HC3N. Then we apply these cross sections and the model atmosphere of Swain et al. to a radiative transfer model in order to simulate the transmission spectrum of GJ 1132 b as it would be seen by JWST, accounting for the uncertainty in the retrieved abundances. We predict that cyanoacetylene features at various wavelengths, with a clear lone feature at 4.5 μm, observable by JWST after one transit. This feature persists within the 1σ uncertainty of the retrieved abundances of HCN and CH4. The signal is detectable for stratospheric temperatures ≲600 K and moderate stratospheric mixing (106 cm2 s−1 ≲ K zz ≲ 108 cm2 s−1). Our results also indicate that HC3N is an important source of opacity that future retrieval models should consider.