cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
ShakeMe: Key Generation From Shared Motion
Creators: name: Yuzuguzel, Hidir
name: Niemi, Jari
name: Kiranyaz, Serkan
name: Gabbouj, Moncef
name: Heinz, Thomas
Publisher: name: arXiv
Year: 2015
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Devices equipped with accelerometer sensors such as today's mobile devices can make use of motion to exchange information. A typical example for shared motion is shaking of two devices which are held together in one hand. Deriving a shared secret (key) from shared motion, e.g. for device pairing, is an obvious application for this. Only the keys need to be exchanged between the peers and neither the motion data nor the features extracted from it. This makes the pairing fast and easy. For this, each device generates an information signal (key) independently of each other and, in order to pair, they should be identical. The key is essentially derived by quantizing certain well discriminative features extracted from the accelerometer data after an implicit synchronization. In this paper, we aim at finding a small set of effective features which enable a significantly simpler quantization procedure than the prior art. Our tentative results with authentic accelerometer data show that this is possible with a competent accuracy ($76$%) and key strength (entropy approximately $15$ bits).
description: The paper is accepted to the 13th IEEE International Conference on Pervasive Intelligence and Computing (PIComp-2015)
Investigation of a Catenane with a Responsive Noncovalent Network: Mimicking Long-Range Responses in Proteins
Creators: name: Lee, Stephen J.
name: Waters, Marcey L.
name: Gagné, Michel R.
name: White, Peter S.
name: Chung, Mee-Kyung
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: We report a functional synthetic model for studying the noncovalent networks (NCNs) required for complex protein functions. The model [2]-catenane is self-assembled from dipeptide building blocks and contains an extensive network of hydrogen bonds and aromatic interactions. Perturbations to the catenane cause compensating changes in the NCNs structure and dynamics, resulting in long-distance changes reminiscent of a protein. Key findings include the notion that NCNs require regions of negative cooperativity, or "frustrated" noncovalent interactions, as a source of potential energy for driving the response. We refer to this potential energy as latent free energy and describe a mechanistic and energetic model for responsive systems.
Experimental protection of 2-qubit quantum gates against environmental noise by dynamical decoupling
Creators: name: Zhang, Jingfu
name: Suter, Dieter
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Hybrid systems consisting of different types of qubits are promising for building quantum computers if they combine useful properties of their constituent qubits. However, they also pose additional challenges if one type of qubits is more susceptible to environmental noise than the others. Dynamical decoupling can help to protect such systems by reducing the decoherence due to the environmental noise, but the protection must be designed such that it does not interfere with the control fields driving the logical operations. Here, we test such a protection scheme on a quantum register consisting of the electronic and nuclear spins of a nitrogen-vacancy center in diamond. The results show that processing is compatible with protection: The dephasing time was extended almost to the limit given by the longitudinal relaxation time of the electron spin.
Palladium-Catalyzed Alkoxycarbonylation of Unactivated Secondary Alkyl Bromides at Low Pressure
Creators: name: Sargent, Brendon T.
name: Alexanian, Erik J.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Catalytic carbonylations of organohalides are important C-C bond formations in chemical synthesis. Carbonylations of unactivated alkyl halides remain a challenge and currently require the use of alkyl iodides under harsh conditions and high pressures of CO. Herein we report a palladium-catalyzed alkoxycarbonylation of secondary alkyl bromides that proceeds at low pressure (2 atm CO) under mild conditions. Preliminary mechanistic studies are consistent with a hybrid organometallic-radical process. These reactions efficiently deliver esters from unactivated alkyl bromides across a diverse range of substrates and represent the first catalytic carbonylations of alkyl bromides with carbon monoxide.
Robust A Posteriori Error Estimation for Finite Element Approximation to H(curl) Problem
Creators: name: Cai, Zhiqiang
name: Cao, Shuhao
name: Falgout, Rob
Publisher: name: arXiv
Year: 2015
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 65N15, 65N30, 65N50

description: In this paper, we introduce a novel a posteriori error estimator for the conforming finite element approximation to the H(curl) problem with inhomogeneous media and with the right-hand side only in L^2. The estimator is of the recovery type. Independent with the current approximation to the primary variable (the electric field), an auxiliary variable (the magnetizing field) is recovered in parallel by solving a similar H(curl) problem. An alternate way of recovery is presented as well by localizing the error flux. The estimator is then defined as the sum of the modified element residual and the residual of the constitutive equation defining the auxiliary variable. It is proved that the estimator is approximately equal to the true error in the energy norm without the quasi-monotonicity assumption. Finally, we present numerical results for two H(curl) interface problems.
Photoacidic and Photobasic Behavior of Transition Metal Compounds with Carboxylic Acid Group(s)
Creators: name: Johansson, Patrik G.
name: Ward, Cassandra L.
name: Sampaio, Renato N.
name: Meyer, Gerald J.
name: Li, Guocan
name: O'Donnell, Ryan M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Excited state proton transfer studies of six Ru polypyridyl compounds with carboxylic acid/carboxylate group(s) revealed that some were photoacids and some were photobases. The compounds [Ru II(btfmb) 2(LL)] 2+, [Ru II(dtb)2(LL)]2+, and [RuII(bpy)2(LL)]2+, where bpy is 2,2'-bipyridine, btfmb is 4,4'-(CF 3) 2-bpy, and dtb is 4,4'-((CH 3) 3C) 2-bpy, and LL is either dcb = 4,4'-(CO 2H) 2-bpy or mcb = 4-(CO 2H),4'-(CO2Et)-2,2'-bpy, were synthesized and characterized. The compounds exhibited intense metal-to-ligand charge-transfer (MLCT) absorption bands in the visible region and room temperature photoluminescence (PL) with long τ > 100 ns excited state lifetimes. The mcb compounds had very similar ground state pKa’s of 2.31 ± 0.07, and their characterization enabled accurate determination of the two pK a values for the commonly utilized dcb ligand, pK a1 = 2.1 ± 0.1 and pKa2 = 3.0 ± 0.2. Compounds with the btfmb ligand were photoacidic, and the other compounds were photobasic. Transient absorption spectra indicated that btfmb compounds displayed a [Ru III(btfmb–)L 2] 2+* localized excited state and a [Ru III(dcb–)L 2] 2+* formulation for all the other excited states. Time dependent PL spectral shifts provided the first kinetic data for excited state proton transfer in a transition metal compound. PLmore » titrations, thermochemical cycles, and kinetic analysis (for the mcb compounds) provided self-consistent pK a* values. The ability to make a single ionizable group photobasic or photoacidic through ligand design was unprecedented and was understood based on the orientation of the lowest-lying MLCT excited state dipole relative to the ligand that contained the carboxylic acid group(s).« less
Post-translational Claisen Condensation and Decarboxylation en Route to the Bicyclic Core of Pantocin A
Creators: name: Redinbo, Matthew R.
name: Bassett, Sarah Jane
name: Biernat, Kristen A.
name: Bowers, Albert A.
name: Ghodge, Swapnil V.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Pantocin A (PA) is a member of the growing family of ribosomally encoded and post-translationally modified peptide natural products (RiPPs). PA is much smaller than most known RiPPs, a tripeptide with a tight bicyclic core that appears to be cleaved from the middle of a larger 30-residue precursor peptide. We show here that the enzyme PaaA catalyzes the double dehydration and decarboxylation of two glutamic acid residues in the 30-residue precursor PaaP. Further truncates of PaaP leader and follower peptide sequences demonstrate the different impacts of these two regions on PaaA-mediated tailoring and delineate an essential role for the follower sequence in the decarboxylation step. The crystal structure of apo PaaA is reported, allowing identification of structural features that set PaaA apart from other homologous enzymes that typically do not catalyze such extended post-translational chemistry. Together, these data reveal how additional chemistry can be extracted from a ubiquitous enzyme family toward ribosomally derived peptide natural product biosynthesis and suggest that more examples of such enzymes likely exist in untapped genomic space.
Multifield Dynamics in Higgs-otic Inflation
Creators: name: Bielleman, S.
name: Ibanez, L. E.
name: Pedro, F. G.
name: Valenzuela, I.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In Higgs-otic inflation a complex neutral scalar combination of the $h^0$ and $H^0$ MSSM Higgs fields plays the role of inflaton in a chaotic fashion. The potential is protected from large trans-Planckian corrections at large inflaton if the system is embedded in string theory so that the Higgs fields parametrize a D-brane position. The inflaton potential is then given by a DBI+CS D-brane action yielding an approximate linear behaviour at large field. The inflaton scalar potential is a 2-field model with specific non-canonical kinetic terms. Previous computations of the cosmological parameters (i.e. scalar and tensor perturbations) did not take into account the full 2-field character of the model, ignoring in particular the presence of isocurvature perturbations and their coupling to the adiabatic modes. It is well known that for generic 2-field potentials such effects may significantly alter the observational signatures of a given model. We perform a full analysis of adiabatic and isocurvature perturbations in the Higgs-otic 2-field model. We show that the predictivity of the model is increased compared to the adiabatic approximation. Isocurvature perturbations moderately feed back into adiabatic fluctuations. However, the isocurvature component is exponentially damped by the end of inflation. The tensor to scalar ratio varies in a region $r=0.08-0.12$, consistent with combined Planck/BICEP results.
description: 35 pages, 11 figures
Two-dimensional localized structures in harmonically forced oscillatory systems
Creators: name: Ma, Y. -P.
name: Knobloch, E.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: Two-dimensional spatially localized structures in the complex Ginzburg-Landau equation with 1:1 resonance are studied near the simultaneous occurrence of a steady front between two spatially homogeneous equilibria and a supercritical Turing bifurcation on one of them. The bifurcation structures of steady circular fronts and localized target patterns are computed in the Turing-stable and Turing-unstable regimes. In particular, localized target patterns grow along the solution branch via ring insertion at the core in a process reminiscent of defect-mediated snaking in one spatial dimension. Axisymmetric oscillons on these solution branches are found to be stable over a wide parameter interval, and subject to various types of instability otherwise. Direct numerical simulations reveal novel depinning dynamics of localized target patterns in the radial direction, and of circular and planar localized hexagonal patterns in the fully two-dimensional system.
description: 29 pages, 24 figures
Nucleosynthesis in neutrino-driven winds in hypernovae
Creators: name: Fujibayashi, Sho
name: Yoshida, Takashi
name: Sekiguchi, Yuichiro
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We investigate the nucleosynthesis in the neutrino-driven winds blown off from a $3M_\odot$ massive proto-neutron star (mPNS) temporarily formed during the collapse of a $100M_\odot$ star. Such mPNSs would be formed in hypernovae. We construct steady and spherically symmetric wind solutions. We set large neutrino luminosities of $\sim 10^{53}\ {\rm erg\ s^{-1}}$ and average energies of electron neutrinos and antineutrinos in the ranges of $ε_{ν_e}=9-16\ {\rm MeV}$ and $ε_{\barν_e}=11-18\ {\rm MeV}$ based on a recent numerical relativity simulation. The wind solutions indicate much shorter temperature-decrease timescale than that of the winds from ordinary PNSs and, depending on $ε_ν$, the winds can be both neutron-rich and proton-rich. In the neutron-rich wind, the $r$-process occurs and the abundance distribution of a fiducial wind model of the mPNS gives an approximate agreement with the abundance pattern of metal-poor weak $r$ star HD~122563, although the third-peak elements are produced only when the $\barν_e$ energy is much larger than the $ν_e$ energy. In the proton-rich wind, the strong $νp$-process occurs and $A>100$ nuclides are synthesized. The synthesized nuclei can be neutron-rich in some cases because the large neutrino luminosity of the mPNS supplies a sufficient amount of neutrons.
description: 20 pages, 17 figures. Accepted for publication in ApJ
Ratiometric Imaging Using a Single Dye Enables Simultaneous Visualization of Rac1 and Cdc42 Activation
Creators: name: Li, Li
name: Liu, Bei
name: Marston, Daniel J.
name: Hahn, Klaus M.
name: Qi, Timothy
name: Nguyen, Dan-Vinh
name: Macnevin, Christopher J.
name: Toutchkine, Alexei
name: Hsu, Chia-Wen
name: Tsygankov, Denis
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Biosensors that report endogenous protein activity in vivo can be based on environment-sensing fluorescent dyes. The dyes can be attached to reagents that bind selectively to a specific conformation of the targeted protein, such that binding leads to a fluorescence change. Dyes that are sufficiently bright for use at low, nonperturbing intracellular concentrations typically undergo changes in intensity rather than the shifts in excitation or emission maxima that would enable precise quantitation through ratiometric imaging. We report here mero199, an environment-sensing dye that undergoes a 33 nm solvent-dependent shift in excitation. The dye was used to generate a ratiometric biosensor of Cdc42 (CRIB199) without the need for additional fluorophores. CRIB199 was used in the same cell with a FRET sensor of Rac1 activation to simultaneously observe Cdc42 and Rac1 activity in cellular protrusions, indicating that Rac1 but not Cdc42 activity was reduced during tail retraction, and specific protrusions had red...
Diffuse approximation to the kinetic theory in a Fermi system
Creators: name: Kolomietz, V. M.
name: Lukyanov, S. V.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We suggest the diffuse approach to the relaxation processes within the kinetic theory for the Wigner distribution function. The diffusion and drift coefficients are evaluated taking into consideration the interparticle collisions on the distorted Fermi surface. Using the finite range interaction, we show that the momentum dependence of the diffuse coefficient $D_{p}(p)$ has a maximum at Fermi momentum $p=p_{F}$ whereas the drift coefficient $K_{p}(p)$ is negative and reaches a minimum at $p\approx p_{F}$. For a cold Fermi system the diffusion coefficient takes the non-zero value which is caused by the relaxation on the distorted Fermi-surface at temperature $T=0$. The numerical solution of the diffusion equation was performed for the particle-hole excitation in a nucleus with $A=16$. The evaluated relaxation time $τ_{r}\approx 8.3\cdot 10^{-23}\mathrm{s}$ is close to the corresponding result in a nuclear Fermi-liquid obtained within the kinetic theory.
description: 16 pages, 6 figures
Site-Selective Aliphatic C–H Chlorination Using N -Chloroamides Enables a Synthesis of Chlorolissoclimide
Creators: name: Horne, David A.
name: Schmidt, Yvonne
name: Nam, Sangkil
name: Alexanian, Erik J.
name: Szklarski, Anne R.
name: Flores, Alex R.
name: Könst, Zef A.
name: Michalak, Sharon E.
name: Vanderwal, Christopher D.
name: Quinn, Ryan K.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Methods for the practical, intermolecular functionalization of aliphatic C-H bonds remain a paramount goal of organic synthesis. Free radical alkane chlorination is an important industrial process for the production of small molecule chloroalkanes from simple hydrocarbons, yet applications to fine chemical synthesis are rare. Herein, we report a site-selective chlorination of aliphatic C-H bonds using readily available N-chloroamides and apply this transformation to a synthesis of chlorolissoclimide, a potently cytotoxic labdane diterpenoid. These reactions deliver alkyl chlorides in useful chemical yields with substrate as the limiting reagent. Notably, this approach tolerates substrate unsaturation that normally poses major challenges in chemoselective, aliphatic C-H functionalization. The sterically and electronically dictated site selectivities of the C-H chlorination are among the most selective alkane functionalizations known, providing a unique tool for chemical synthesis. The short synthesis of chlorolissoclimide features a high yielding, gram-scale radical C-H chlorination of sclareolide and a three-step/two-pot process for the introduction of the β-hydroxysuccinimide that is salient to all the lissoclimides and haterumaimides. Preliminary assays indicate that chlorolissoclimide and analogues are moderately active against aggressive melanoma and prostate cancer cell lines.
Derived Categories of Artin-Mumford double solids
Creators: name: Hosono, Shinobu
name: Takagi, Hiromichi
Publisher: name: arXiv
Year: 2015
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We consider the derived category of an Artin-Mumford quartic double solid blown-up at ten ordinary double points. We show that it has a semi-orthogonal decomposition containing the derived category of the Enriques surface of a Reye congruence. This answers affirmatively a conjecture by Ingalls and Kuznetsov.
description: We have moved some techinical staffs into our papers [24] and [25] in the reference
Direct C–H Cyanation of Arenes via Organic Photoredox Catalysis
Creators: name: McManus, Joshua B.
name: Nicewicz, David A.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Methods for the direct C–H functionalization of aromatic compounds are in demand for a variety of applications, including the synthesis of agrochemicals, pharmaceuticals, and materials. Herein, we disclose the construction of aromatic nitriles via direct C–H functionalization using an acridinium photoredox catalyst and trimethylsilyl cyanide under an aerobic atmosphere. The reaction proceeds at room temperature under mild conditions and has proven to be compatible with a variety of electron-donating and -withdrawing groups, halogens, and nitrogen- and oxygen-containing heterocycles, as well as aromatic-containing pharmaceutical agents.
Maximizing the Photocatalytic Activity of Metal–Organic Frameworks with Aminated-Functionalized Linkers: Substoichiometric Effects in MIL-125-NH 2
Creators: name: Sanchez, Clément
name: Rozes, Laurence
name: Wang, Xia
name: Ersen, Ovidiu
name: Fontecave, Marc
name: Mellot-Draznieks, Caroline
name: Ellezam, Laura
name: Chambers, Matthew B.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Despite the promise of utilizing metal-organic frameworks (MOFs) as highly tunable photocatalytic materials , systematic studies that interrogate the relationship between their catalytic performances and the amount of function-alized linkers are lacking. Aminated linkers are known to enhance the absorption of light and afford photocatalysis with MOFs under visible-light irradiation. However, the manner in which the photocatalytic performances are impacted by the amount of such linkers is poorly understood. Here, we assess the photocatalytic activity of MIL-125, a TiO 2 /1,4-benzenedicarboxylate (bdc) MOF for the oxidation of benzyl alcohol to benzaldehyde when increasing amounts of bdc-NH 2 linkers (0%, 20%, 46%, 70% and 100%) are incorporated in the framework. Analytical TEM allowed assessing the homogeneous localization of bdc-NH 2 in these mixed-linker MOFs. Steady state reaction rates reveal two regimes of catalytic performances: a first linear regime up to ~50% bdc-NH 2 into the hybrid framework whereby increased amounts of bdc-NH 2 yielded increased photocatalytic rates, followed by a plateau up to 100% bdc-NH 2. This unexpected " saturation " of the catalytic activity above ~50% bdc-NH 2 content in the framework whatever the wavelength filters used, demonstrates that amination of all linkers of the MOF is not required to obtain the maximum photocatalytic activity. This is rationalized on the basis of mixed-valence Ti 3+ /Ti 4+ intermediate catalytic centers revealed by Electron Spin Resonance measurements and recent knowledge of lifetime excited states in MIL-125-type of solids.
Numerical studies of entanglement properties in one- and two-dimensional quantum Ising and XXZ models
Creators: name: Braiorr-Orrs, B.
name: Weyrauch, M.
name: Rakov, M. V.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We investigate entanglement properties of infinite 1D and 2D spin-1/2 quantum Ising and XXZ models. Tensor network methods (MPS in 1D and TERG and CTMRG in 2D) are used to model the ground state of the studied models. Different entanglement measures, such as one-site entanglement entropy, one-tangle, concurrence of formation and assistance, negativity and entanglement per bond are calculated and their `characterizing power' to determine quantum phase transitions is compared. A special emphasis is made on the study of entanglement monogamy properties.
description: 19 pages, 24 figures
Synthesis of Complex Tertiary Glycolates by Enantioconvergent Arylation of Stereochemically Labile α-Keto Esters
Creators: name: Bartlett, Samuel L.
name: Johnson, Jeffrey S.
name: Keiter, Kimberly M.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Enantioconvergent arylation reactions of boronic acids and racemic β-stereogenic α-keto esters have been developed. The reactions are catalyzed by a chiral (diene)Rh(I) complex and provide a wide array of β-stereogenic tertiary aryl glycolate derivatives with high levels of diastereo- and enantioselectivity. Racemization studies employing a series of sterically differentiated tertiary amines suggest that the steric nature of the amine base additive exerts a significant influence on the rate of substrate racemization.
Ferromagnetic resonance of coupled shifted chains of nano-elements
Creators: name: Bastardis, Roland
name: Déjardin, Jean-Louis
name: Vernay, François
name: Kachkachi, Hamid
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We investigate the FMR characteristics of a magnetic dimer composed of two chains of iron nanoparticles coupled by dipolar interactions. The latter are treated beyond the point-dipole approximation taking into account the finite size and arbitrary shape of the nano-elements. The resonance frequency is calculated as a function of the amplitude of the applied magnetic field and the resonance field is computed as a function of the direction of the applied field, varied both in the plane of the two chains and perpendicular to it. We highlight a critical value of the magnetic field which marks a state transition that should be important in magnetic recording media.
Criticality and Big Brake singularities in the tachyonic evolutions of closed Friedmann universes with cold dark matter
Creators: name: Horváth, Zsolt
name: Keresztes, Zoltán
name: Kamenshchik, Alexander Yu.
name: Gergely, László Á.
Publisher: name: arXiv
Year: 2015
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The evolution of a closed Friedmann universe filled by a tachyon scalar field with a trigonometric potential and cold dark matter (CDM) is investigated. A subset of the evolutions consistent to 1$σ$ confidence level with the Union 2.1 supernova data set is identified. The evolutions of the tachyon field are classified. Some of them evolve into a de Sitter attractor, while others proceed through a pseudo-tachyonic regime into a sudden future singularity. Critical evolutions leading to Big Brake singularities in the presence of CDM are found and a new type of cosmological evolution characterized by singularity avoidance in the pseudo-tachyon regime is presented.
description: 7 pages, 5 figures, to be published in Phys. Rev. D
A planar Al-Si Schottky Barrier MOSFET operated at cryogenic temperatures
Creators: name: Purches, Wendy E.
name: Rossi, Alessandro
name: Zhao, Ruichen
name: Kafanov, Sergey
name: Duty, Timothy L.
name: Dzurak, Andrew S.
name: Rogge, Sven
name: Tettamanzi, Giuseppe C.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Schottky Barrier (SB)-MOSFET technology offers intriguing possibilities for cryogenic nano-scale devices, such as Si quantum devices and superconducting devices. We present experimental results on a novel device architecture where the gate electrode is self-aligned with the device channel and overlaps the source and drain electrodes. This facilitates a sub-5 nm gap between the source/drain and channel, and no spacers are required. At cryogenic temperatures, such devices function as p-MOS Tunnel FETs, as determined by the Schottky barrier at the Al-Si interface, and as a further advantage, fabrication processes are compatible with both CMOS and superconducting logic technology.
description: 6 pages, 4 figures, minor changes from the previous version 1
A spin liquid with pinch-line singularities on the pyrochlore lattice
Creators: name: Benton, Owen
name: Jaubert, Ludovic D. C.
name: Yan, Han
name: Shannon, Nic
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The mathematics of gauge theories lies behind many of the most profound advances in physics in the last 200 years, from Maxwell's theory of electromagnetism to Einstein's theory of general relativity. More recently it has become clear that gauge theories also emerge in condensed matter, a prime example being the spin ice materials which host an emergent electromagnetic gauge field. In spin ice, the underlying gauge structure is revealed by the presence of pinch-point singularities in neutron-scattering measurements. Here we report the discovery of a spin liquid where the low-temperature physics is naturally described by the fluctuations of a tensor field with a continuous gauge freedom. This gauge structure underpins an unusual form of spin correlations, giving rise to pinch-line singularities--- line-like analogues of the pinch-points observed in spin ice. Remarkably, these features may already have been observed in the pyrochlore material Tb$_2$Ti$_2$O$_7$.
description: 4 pages of main text, 3 figures
title: Kritik und Reform des Jurastudiums
Creators: name: Paskowski, Christopher
name: Früchtenicht, Sophie
name: Hanschmann, Felix
name: Fischer-Lescano, Andreas
Publisher: name: Fachinformationsdienst für internationale und interdisziplinäre Rechtsforschung
Year: 2024
Subjects: subject: 342

description: Verfassungsblog: On Matters Constitutional
Cystatin C and Cardiovascular Disease: A Mendelian Randomization Study
Creators: name: Zabaneh, Delilah
name: Eriksen, Bjørn Odvar
name: Isgum, Ivana
name: Peters, Annette
name: O'Donnell, Christopher
name: Meisinger, Christa
name: Schunkert, Heribert
name: Koenig, Wolfgang
name: Morrison, Alanna C.
name: Hofman, Albert
name: Erdmann, Jeanette
name: Kiemeney, Lambertus A.L.M.
name: Pasterkamp, Gerard
name: Toft, Ingrid
name: Pedersen, Nancy L.
name: Franceschini, Nora
name: Kumari, Meena
name: Wilsgaard, Tom
name: Samani, Nilesh J.
name: Baumert, Jens
name: Onland-Moret, N. Charlotte
name: Felix, Janine F.
name: Holmes, Michael V.
name: Debette, Stéphanie
name: Larsson, Anders
name: Ingelsson, Erik
name: Sedaghat, Sanaz
name: de Graaf, Jacqueline
name: Amouyel, Philippe
name: Nelson, Christopher P.
name: Tragante, Vinicius
name: Kavousi, Maryam
name: Magnusson, Patrik K.
name: Morris, Andrew P.
name: Uitterlinden, André G.
name: Keating, Brendan J.
name: Worrall, Bradford B.
name: Kivimaki, Mika
name: Lind, Lars
name: Giedraitis, Vilmantas
name: Trompet, Stella
name: Svensson, Per
name: Waldenberger, Melanie
name: de Bakker, Paul I.W.
name: Reiner, Alex P.
name: van Setten, Jessica
name: Ärnlöv, Johan
name: den Ruijter, Hester M.
name: van der Harst, Pim
name: Thorand, Barbara
name: van der Schouw, Yvonne T.
name: Marchini, Jonathan
name: Galesloot, Tessel E.
name: Drenos, Fotios
name: Dichgans, Martin
name: van der Laan, Sander W.
name: Baumeister, Sebastian E.
name: Munroe, Patricia B.
name: Soumaré, Aicha
name: Malik, Rainer
name: Jukema, J. Wouter
name: Fall, Tove
name: Patel, Riyaz S.
name: Asselbergs, Folkert W.
name: Franco, Oscar H.
name: Dörr, Marcus
name: Bis, Joshua C.
name: Sattar, Naveed
name: Teumer, Alexander
name: Dehghan, Abbas
name: Hingorani, Aroon D.
name: Arpegård, Johannes
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Epidemiological studies show that high circulating cystatin C is associated with risk of cardiovascular disease (CVD), independent of creatinine-based renal function measurements. It is unclear whether this relationship is causal, arises from residual confounding, and/or is a consequence of reverse causation.
Biases and systematics in the observational derivation of galaxy properties: comparing different techniques on synthetic observations of simulated galaxies
Creators: name: Guidi, Giovanni
name: Scannapieco, Cecilia
name: Walcher, C. Jakob
Publisher: name: arXiv
Year: 2015
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We study the sources of biases and systematics in the derivation of galaxy properties of observational studies, focusing on stellar masses, star formation rates, gas/stellar metallicities, stellar ages and magnitudes/colors. We use hydrodynamical cosmological simulations of galaxy formation, for which the real quantities are known, and apply observational techniques to derive the observables. We also make an analysis of biases that are relevant for a proper comparison between simulations and observations. For our study, we post-process the simulation outputs to calculate the galaxies' spectral energy distributions (SEDs) using Stellar Population Synthesis models and also generating the fully-consistent far UV-submillimeter wavelength SEDs with the radiative transfer code SUNRISE. We compared the direct results of simulations with the observationally-derived quantities obtained in various ways, and found that systematic differences in all studied galaxy properties appear, which are caused by: (1) purely observational biases, (2) the use of mass-weighted/luminosity-weighted quantities, with preferential sampling of more massive/luminous regions, (3) the different ways to construct the template of models when a fit to the spectra is performed, and (4) variations due to the use of different calibrations, most notably in the cases of the gas metallicities and star formation rates. Our results show that large differences can appear depending on the technique used to derive galaxy properties. Understanding these differences is of primary importance both for simulators, to allow a better judgement on similarities/differences with observations, and for observers, to allow a proper interpretation of the data.
description: 22 pages, 14 figures, 2 tables, MNRAS accepted
Do Brain Networks Evolve by Maximizing their Information Flow Capacity?
Creators: name: Antonopoulos, Chris G.
name: Srivastava, Shambhavi
name: Pinto, Sandro E. de S.
name: Baptista, Murilo S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Molecular Networks (q-bio.MN)
subject: FOS: Biological sciences

description: We propose a working hypothesis supported by numerical simulations that brain networks evolve based on the principle of the maximization of their internal information flow capacity. We find that synchronous behavior and capacity of information flow of the evolved networks reproduce well the same behaviors observed in the brain dynamical networks of Caenorhabditis elegans and humans, networks of Hindmarsh-Rose neurons with graphs given by these brain networks. We make a strong case to verify our hypothesis by showing that the neural networks with the closest graph distance to the brain networks of Caenorhabditis elegans and humans are the Hindmarsh-Rose neural networks evolved with coupling strengths that maximize information flow capacity. Surprisingly, we find that global neural synchronization levels decrease during brain evolution, reflecting on an underlying global no Hebbian-like evolution process, which is driven by no Hebbian-like learning behaviors for some of the clusters during evolution, and Hebbian-like learning rules for clusters where neurons increase their synchronization.
description: 27 pages, 8 figures, 2 tables, supporting_information included, published in PLOS Computational Biology
Potential Impact of Time Trend of Life-Style Factors on Cardiovascular Disease Burden in China
Creators: name: Ley, Sylvia H.
name: He, Yuna
name: Hu, Frank B.
name: Howard, Annie Green
name: Li, Yanping
name: Wang, Dong D.
name: Danaei, Goodarz
name: Lu, Yuan
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Cardiovascular disease (CVD) is a leading cause of death in China. Evaluation of risk factors and their impacts on disease burden is important for future public health initiatives and policy making.
Information-theoretical analysis of the statistical dependencies among three variables: Applications to written language
Creators: name: Hernández, Damián G.
name: Zanette, Damián H.
name: Samengo, Inés
Publisher: name: arXiv
Year: 2015
Subjects: subject: Computation and Language (cs.CL)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: We develop the information-theoretical concepts required to study the statistical dependencies among three variables. Some of such dependencies are pure triple interactions, in the sense that they cannot be explained in terms of a combination of pairwise correlations. We derive bounds for triple dependencies, and characterize the shape of the joint probability distribution of three binary variables with high triple interaction. The analysis also allows us to quantify the amount of redundancy in the mutual information between pairs of variables, and to assess whether the information between two variables is or is not mediated by a third variable. These concepts are applied to the analysis of written texts. We find that the probability that a given word is found in a particular location within the text is not only modulated by the presence or absence of other nearby words, but also, on the presence or absence of nearby pairs of words. We identify the words enclosing the key semantic concepts of the text, the triplets of words with high pairwise and triple interactions, and the words that mediate the pairwise interactions between other words.
Testosterone and Cardiovascular Disease
Creators: name: Kloner, Robert A.
name: Mohler, Emile R.
name: Kopecky, Stephen
name: Carson, Culley
name: Dobs, Adrian
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Abstract Testosterone (T) is the principal male sex hormone. As men age, T levels typically fall. Symptoms of low T include decreased libido, vasomotor instability, and decreased bone mineral density. Other symptoms may include depression, fatigue, erectile dysfunction, and reduced muscle strength/mass. Epidemiology studies show that low levels of T are associated with more atherosclerosis, coronary artery disease, and cardiovascular events. However, treating hypogonadism in the aging male has resulted in discrepant results in regard to its effect on cardiovascular events. Emerging studies suggest that T may have a future role in treating heart failure, angina, and myocardial ischemia. A large, prospective, long-term study of T replacement, with a primary endpoint of a composite of adverse cardiovascular events including myocardial infarction, stroke, and/or cardiovascular death, is needed. The Food and Drug Administration recently put additional restrictions on T replacement therapy labeling and called for additional studies to determine its cardiac safety.
Correlation between Galaxy Mergers and Luminous AGN
Creators: name: Hong, Jueun
name: Im, Myungshin
name: Kim, Minjin
name: Ho, Luis C.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: It is not yet clear what triggers the activity of active galactic nuclei (AGNs), but galaxy merging has been suspected to be one of the main mechanisms fuelling the activity. Using deep optical images taken at various ground-based telescopes, we investigate the fraction of galaxy mergers in 39 luminous AGNs (M$_{R}\, \lesssim$ -22.6 mag) at $z \leq$ 0.3 (a median redshift of 0.155), of which the host galaxies are generally considered as early-type galaxies. Through visual inspection of the images, we find that 17 of 39 AGN host galaxies (43.6%) show the evidence for current or past mergers like tidal tails, shells, and disturbed morphology. In order to see if this fraction is abnormally high, we also examined the merging fraction of normal early-type galaxies in the Sloan Digital Sky Survey (SDSS) Strip 82 data (a median redshift of 0.04), of which the surface-brightness limit is comparable to our imaging data. To correct for the effects related to the redshift difference of the two samples, we performed an image simulation by putting a bright point source as an artificial AGN in the images of SDSS early-type galaxies and placing them onto the redshifts of AGNs. The merging fraction in this realistic sample of simulated AGNs is only $\sim 5 - 15\%$ ($1/4$ to $1/8$ of that of real AGNs). Our result strongly suggests that luminous AGN activity is associated with galaxy merging.
description: 57 pages, 19 figures, published in Astrophysical Journal
Adherence Tradeoff to Multiple Preventive Therapies and All-Cause Mortality After Acute Myocardial Infarction
Creators: name: Fang, Gang
name: Korhonen, Maarit J.
name: Hartikainen, Juha
name: Robinson, Jennifer G.
name: Hickson, Ryan P.
name: Annis, Izabela E.
name: Bell, J. Simon
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Angiotensin-converting enzyme (ACE) inhibitors/angiotensin II receptor blockers (ARB), beta-blockers and statins are recommended after acute myocardial infarction (AMI). Patients may adhere to some, but not all, therapies.The authors investigated the effect of tradeoffs in adherence to ACE inhibitors/ARBs, beta-blockers, and statins on survival among older people after AMI.The authors identified 90,869 Medicare beneficiaries ≥65 years of age who had prescriptions for ACE inhibitors/ARBs, beta-blockers, and statins, and survived ≥180 days after AMI hospitalization in 2008 to 2010. Adherence was measured by proportion of days covered (PDC) during 180 days following hospital discharge. Mortality follow-up extended up to 18 months after this period. The authors used Cox proportional hazards models to estimate hazard ratios of mortality for groups adherent to 2, 1, or none of the therapies versus group adherent to all 3 therapies.Only 49% of the patients adhered (PDC ≥80%) to all 3 therapies. Compared with being adherent to all 3 therapies, multivariable-adjusted hazard ratios (95% confidence intervals [CIs]) for mortality were 1.12 (95% CI: 1.04 to 1.21) for being adherent to ACE inhibitors/ARBs and beta-blockers only, 0.98 (95% CI: 0.91 to 1.07) for ACEI/ARBs and statins only, 1.17 (95% CI: 1.10 to 1.25) beta-blockers and statins only, 1.19 (95% CI: 1.07 to 1.32) for ACE inhibitors/ARBs only, 1.32 (95% CI: 1.21 to 1.44) for beta-blockers only, 1.26 (95% CI: 1.15 to 1.38) statins only, and 1.65 (95% CI: 1.54 to 1.76) for being nonadherent (PDC <80%) to all 3 therapies.Patients adherent to ACE inhibitors/ARBs and statins only had similar mortality rates as those adherent to all 3 therapies, suggesting limited additional benefit for beta-blockers in patients who were adherent to statins and ACE inhibitors/ARBs. Nonadherence to ACE inhibitors/ARBs and/or statins was associated with higher mortality.
Comment on "Universal decoherence due to gravitational time dilation"
Creators: name: Bonder, Yuri
name: Okon, Elias
name: Sudarsky, Daniel
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We present a series of arguments against the results of the paper "Universal decoherence due to gravitational time dilation" by Pikovski et al. (arXiv:1311.1095).
description: Replaced to match the accepted comment (Nature Physics)
On the Exact and Approximate Eigenvalue Distribution for Sum of Wishart Matrices
Creators: name: Kumar, S.
name: Pivaro, G. F.
name: Fraidenraich, G.
name: Dias, C. F.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences
subject: 94A15, 94A17, 15A18, 15B52

description: The sum of Wishart matrices has an important role in multiuser communication employing multiantenna elements, such as multiple-input multiple-output (MIMO) multiple access channel (MAC), MIMO Relay channel, and other multiuser channels where the mathematical model is best described using random matrices. In this paper, the distribution of linear combination of complex Wishart distributed matrices has been studied. We present a new closed form expression for the marginal distribution of the eigenvalues of a weighted sum of K complex central Wishart matrices having covariance matrices proportional to the identity matrix. The expression is general and allows for any set of linear coefficients. As an application example, we have used the marginal distribution expression to obtain the ergodic sum-rate capacity for the MIMO-MAC network, and the cut-set upper bound for the MIMO-Relay case, both as closed form expressions. We also present a very simple expression to approximate the sum of Wishart matrices by one equivalent Wishart matrix. All of our results are validated by means of Monte Carlo simulations. As expected, the agreement between the exact eigenvalue distribution and simulations is perfect, whereas for the approximate solution the difference is indistinguishable.
description: 18 pages, 8 figures, 1 table
A stochastic density matrix approach to approximation of probability distributions and its application to nonlinear systems
Creators: name: Vladimirov, Igor G.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Probability (math.PR)
subject: Systems and Control (eess.SY)
subject: Analysis of PDEs (math.AP)
subject: Numerical Analysis (math.NA)
subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: 62E17, 93E03, 60J60, 35Q84, 42B37, 42C05, 65K10, 93B40

description: This paper outlines an approach to the approximation of probability density functions by quadratic forms of weighted orthonormal basis functions with positive semi-definite Hermitian matrices of unit trace. Such matrices are called stochastic density matrices in order to reflect an analogy with the quantum mechanical density matrices. The SDM approximation of a PDF satisfies the normalization condition and is nonnegative everywhere in contrast to the truncated Gram-Charlier and Edgeworth expansions. For bases with an algebraic structure, such as the Hermite polynomial and Fourier bases, the SDM approximation can be chosen so as to satisfy given moment specifications and can be optimized using a quadratic proximity criterion. We apply the SDM approach to the Fokker-Planck-Kolmogorov PDF dynamics of Markov diffusion processes governed by nonlinear stochastic differential equations. This leads to an ordinary differential equation for the SDM dynamics of the approximating PDF. As an example, we consider the Smoluchowski SDE on a multidimensional torus.
description: 12 pages, 3 figures. A brief version of this paper will appear in the proceedings of the IEEE Multi-Conference on Systems and Control, 21-23 September 2015, Sydney, Australia
Cardiac Autonomic Dysfunction and Incidence of Atrial Fibrillation
Creators: name: Alonso, Alvaro
name: Whitsel, Eric A.
name: Norby, Faye L.
name: Loehr, Laura R.
name: Fuster, Valentin
name: Chen, Lin Y.
name: Coresh, Josef
name: Heiss, Gerardo
name: Agarwal, Sunil K.
name: Soliman, Elsayed Z.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Cardiac autonomic perturbations frequently antecede onset of paroxysmal atrial fibrillation (AF). Interventions that influence autonomic inputs to myocardium may prevent AF. However, whether low heart rate or heart rate variability (HRV), which are noninvasive measures of cardiac autonomic dysfunction, are associated with AF incidence is unclear.