cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Energy-Efficient Resource Allocation in Multiuser OFDM Systems with Wireless Information and Power Transfer
Creators: name: Ng, Derrick Wing Kwan
name: Lo, Ernest S.
name: Schober, Robert
Publisher: name: arXiv
Year: 2012
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: In this paper, we study the resource allocation algorithm design for multiuser orthogonal frequency division multiplexing (OFDM) downlink systems with simultaneous wireless information and power transfer. The algorithm design is formulated as a non-convex optimization problem for maximizing the energy efficiency of data transmission (bit/Joule delivered to the users). In particular, the problem formulation takes into account the minimum required system data rate, heterogeneous minimum required power transfers to the users, and the circuit power consumption. Subsequently, by exploiting the method of time-sharing and the properties of nonlinear fractional programming, the considered non-convex optimization problem is solved using an efficient iterative resource allocation algorithm. For each iteration, the optimal power allocation and user selection solution are derived based on Lagrange dual decomposition. Simulation results illustrate that the proposed iterative resource allocation algorithm achieves the maximum energy efficiency of the system and reveal how energy efficiency, system capacity, and wireless power transfer benefit from the presence of multiple users in the system.
description: 6 pages. The paper has been accepted for publication at the IEEE Wireless Communications and Networking Conference (WCNC) 2013, Shanghai, China, Apr. 2013
Comparing Equivalent Gravities: common features and differences
Creators: name: Capozziello, Salvatore
name: De Falco, Vittorio
name: Ferrara, Carmen
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss equivalent representations of gravity in the framework of metric-affine geometries pointing out basic concepts from where these theories stem out. In particular, we take into account tetrads and spin connection to describe the so called {\it Geometric Trinity of Gravity}. Specifically, we consider General Relativity, constructed upon the metric tensor and based on the curvature $R$; Teleparallel Equivalent of General Relativity, formulated in terms of torsion $T$ and relying on tetrads and spin connection; Symmetric Teleparallel Equivalent of General Relativity, built up on non-metricity $Q$, constructed from metric tensor and affine connection. General Relativity is formulated as a geometric theory of gravity based on metric, whereas teleparallel approaches configure as gauge theories, where gauge choices permit not only to simplify calculations, but also to give deep insight into the basic concepts of gravitational field. In particular, we point out how foundation principles of General Relativity (i.e the Equivalence Principle and the General Covariance) can be seen from the teleparallel point of view. These theories are dynamically equivalent and this feature can be demonstrated under three different standards: (1) the variational method; (2) the field equations; (3) the solutions.
description: 30 pages, 6 figures
Radio ads; recorder tests; Mutual Black Network News radio - music interspersed with news reports
Creators: name: (:Unav)
Publisher: name: Columbia University
Year: 2021
Subjects: Political campaigns
Women--Political activity
Advertising, Political

description: Tape 01 - Side 1 is sound tests for Abzug radio ads, side 2 is Abzug radio ads in English and Spanish. Tape 02 - Short recorder test. Tape 03 - Recording from "Mutual Black Network News" radio - music interspersed with news reports. Tape 04 - Recorder tests. May include someone showing Bella Abzug how to use the recorder (not sure, but sounds like her)
The Weak Neutral Current
Creators: name: Erler, Jens
name: Su, Shufang
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: This is a review of electroweak precision physics with particular emphasis on low-energy precision measurements in the neutral current sector of the electroweak theory and includes future experimental prospects and the theoretical challenges one faces to interpret these observables. Within the minimal Standard Model they serve as determinations of the weak mixing angle which are competitive with and complementary to those obtained near the Z-resonance. In the context of new physics beyond the Standard Model these measurements are crucial to discriminate between models and to reduce the allowed parameter space within a given model. We illustrate this for the minimal supersymmetric Standard Model with or without R-parity.
description: 43 pages, 10 figures
Additional file 1 of Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird
Creators: name: Mentesana, Lucia
name: Andersson, Martin N.
name: Casagrande, Stefania
name: Goymann, Wolfgang
name: Isaksson, Caroline
name: Hau, Michaela
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Ecology

description: Additional file 1. Principal component analysis of 31 yolk components measured in the fourth egg of 69 wild great tit clutches.
Qubit Vitrification and Entanglement Criticality on a Quantum Simulator
Creators: name: Côté, Jeremy
name: Kourtis, Stefanos
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Many elusive quantum phenomena emerge from the interaction of a quantum system with its classical environment. Quantum simulators enable us to program this interaction by using measurement operations. Measurements generally remove part of the quantum entanglement built between the qubits inside a simulator. While in simple cases entanglement may disappear at a constant rate as we measure qubits one by one, the evolution of entanglement under measurements for a given class of quantum states is generally unknown. Here, we show that consecutive measurements of the qubits in a quantum simulator can lead to criticality, separating two phases of entanglement. We prepare an entangled superposition of ground states to a classical spin model and show that progressively measuring the qubits drives the simulator into a spin glass phase of entanglement. By entangling and measuring up to 48 qubits in this fashion, we determine the vitrification point and its critical exponent, which obey spin glass theory exactly. Our findings show that measurements alone can trigger entanglement criticality and suggest that coupling to a classical environment can drive critical phenomena in more general quantum states.
description: Updated to reflect published version
Modeling the Atomic-to-Molecular Transition and Chemical Distributions of Turbulent Star-Forming Clouds
Creators: name: Offner, Stella S. R.
name: Bisbas, Thomas G.
name: Viti, Serena
name: Bell, Thomas A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We use 3D-PDR, a three-dimensional astrochemistry code for modeling photodissociation regions (PDRs), to post-process hydrodynamic simulations of turbulent, star-forming clouds. We focus on the transition from atomic to molecular gas, with specific attention to the formation and distribution of H, C+, C, H2 and CO. First, we demonstrate that the details of the cloud chemistry and our conclusions are insensitive to the simulation spatial resolution, to the resolution at the cloud edge, and to the ray angular resolution. We then investigate the effect of geometry and simulation parameters on chemical abundances and find weak dependence on cloud morphology as dictated by gravity and turbulent Mach number. For a uniform external radiation field, we find similar distributions to those derived using a one-dimensional PDR code. However, we demonstrate that a three-dimensional treatment is necessary for a spatially varying external field, and we caution against using one-dimensional treatments for non-symmetric problems. We compare our results with the work of Glover et al. (2010), who self-consistently followed the time evolution of molecule formation in hydrodynamic simulations using a reduced chemical network. In general, we find good agreement with this in situ approach for C and CO abundances. However, the temperature and H2 abundances are discrepant in the boundary regions (Av < 5), which is due to the different number of rays used by the two approaches.
description: 18 pages, 18 Figures, accepted to ApJ
Dissecting kinetically coupled quintessence: phenomenology and observational tests
Creators: name: Teixeira, Elsa M.
name: Barros, Bruno J.
name: Ferreira, Vasco M. C.
name: Frusciante, Noemi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate an interacting dark energy model which allows for the kinetic term of the scalar field to couple to dark matter via a power-law interaction. The model is characterised by scaling solutions at early times, which are of high interest to alleviate the coincidence problem, followed by a period of accelerated expansion. We discuss the phenomenology of the background evolution and of the linear scalar perturbations and we identify measurable signatures of the coupling in the dark sector on the cosmic microwave background, the lensing potential auto-correlation and the matter power spectra. We also perform a parameter estimation analysis using data of cosmic microwave background temperature, polarisation and lensing, baryonic acoustic oscillations and supernovae. We find that the strength of the coupling between the dark sectors, regulated by the parameter $α$, is constrained to be of order $10^{-4}$. A model selection analysis does not reveal a statistical preference between $Λ$CDM and the Kinetic model.
description: V2: minor corrections, 24 pages, 12 figures, 4 tables, matches published version
Additional file 2 of Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird
Creators: name: Mentesana, Lucia
name: Andersson, Martin N.
name: Casagrande, Stefania
name: Goymann, Wolfgang
name: Isaksson, Caroline
name: Hau, Michaela
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Ecology

description: Additional file 2. Results of linear models and linear mixed-effects models to test for relationships between yolk composition and fitness traits.
Quantum Coherence Tomography of Lightwave Controlled Superconductivity
Creators: name: Luo, L.
name: Mootz, M.
name: Kang, J. H.
name: Huang, C.
name: Eom, K.
name: Lee, J. W.
name: Vaswani, C.
name: Collantes, Y. G.
name: Hellstrom, E. E.
name: Perakis, I. E.
name: Eom, C. B.
name: Wang, J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Lightwave periodic driving of nearly dissipation-less currents has recently emerged as a universal control concept for both superconducting (SC) and topological electronics applications. While exciting progress has been made towards THz-driven superconductivity, our understanding of the interactions able to drive non-equilibrium pairing is still limited, partially due to the lack of direct measurements of high-order correlation functions. Such measurements would exceed conventional single-particle spectroscopies and perturbative responses to fully characterize quantum states far-from-equilibrium. Particularly, sensing of the exotic collective modes that would uniquely characterize lightwave-driven SC coherence, in a way analogous to the Meissner effect, is very challenging but much needed. Here we report the discovery of lightwave-controlled superconductivity via parametric time-periodic driving of the strongly-coupled bands in iron-based superconductors by a unique phase-amplitude collective mode assisted by broken-symmetry THz supercurrents. We are able to measure non-perturbative, high-order correlations in this strongly-driven superconductivity by separating the THz multi-dimensional coherent spectra into conventional pump-probe, Higgs collective mode, and pronounced bi--Higgs frequency sideband peaks with highly nonlinear field dependence. We attribute the drastic transition in the coherent spectra to parametric excitation of time-dependent pseudo--spin canting states modulated by a phase-amplitude collective mode that manifests as a strongly nonlinear shift from $ω_\mathrm{Higgs}$ to 2$ω_\mathrm{Higgs}$. Remarkably, the latter higher--order sidebands dominate over the lower-order pump-probe and Higgs mode peaks above critical field, which indicates the breakdown of the susceptibility perturbative expansion in the parametrically-driven SC state.
Ultra-Deep Hubble Space Telescope Imaging of the Small Magellanic Cloud: The Initial Mass Function of Stars with M
Creators: name: Kalirai, Jason S.
name: Anderson, Jay
name: Dotter, Aaron
name: Richer, Harvey B.
name: Fahlman, Gregory G.
name: Hansen, Brad M. S.
name: Hurley, Jarrod
name: Reid, I. Neill
name: Rich, R. Michael
name: Shara, Michael M.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a new measurement of the stellar initial mass function (IMF) based on ultra-deep, high-resolution photometry of >5,000 stars in the outskirts of the Small Magellanic Cloud (SMC) galaxy. The Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) observations reveal this rich, co-spatial population behind the foreground globular cluster 47 Tuc, which we targeted for 121 HST orbits. The stellar main sequence of the SMC is measured in the F606W, F814W color-magnitude diagram (CMD) down to ~30th magnitude, and is cleanly separated from the foreground star cluster population using proper motions. We simulate the SMC population by extracting stellar masses (single and unresolved binaries) from specific IMFs, and converting those masses to luminosities in our bandpasses. The corresponding photometry for these simulated stars is drawn directly from a rich cloud of 4 million artificial stars, thereby accounting for the real photometric scatter and completeness of the data. Over a continuous and well populated mass range of M = 0.37 - 0.93 Msun (i.e., down to a ~75% completeness limit at F606W = 28.7), we demonstrate that the IMF is well represented by a single power-law form with slope α= -1.90 (^{+0.15}_{-0.10}) (3 sigma error) (i.e., dN/dM \propto M^α). This is shallower than the Salpeter slope of α= -2.35, which agrees with the observed stellar luminosity function at higher masses. Our results indicate that the IMF does {\it not} turn over to a more shallow power-law form within this mass range. We discuss implications of this result for the theory of star formation, the inferred masses of galaxies, and the (lack of a) variation of the IMF with metallicity.
description: 9 pages, 5 figures, 1 table. Accepted for publication in ApJ. Minor revisions to second version based on ApJ proofs. Error bar on IMF slope clarified as 3-sigma interval
title: Comparativ, Vol. 33 No. 3 (2023): Between Trade and Aid: Theories, Practices, and Results of Attempts at Exporting State-Socialist Development Models to the Third World
title: Between Trade and Aid: Theories, Practices, and Results of Attempts at Exporting State-Socialist Development Models to the Third World
titleType: AlternativeTitle
Creators: name: Comparativ
Publisher: name: Comparativ
Year: 2023

description: Self-help Architecture in the Global Cold War: East German Panel Technology for the ANC, 1982–1992...421-439 Long-term Investment or Shortterm Profit? The Divergence of Views on Technical Assistance to Algeria Between the Yugoslav Authorities and Self-managing Enterprises...400-420 Opening Up to the “Third World” or Taking a Detour to the “West”? The Hungarian Presence in Algeria from the 1960s to the 1980s ...377-399 Between Second and Third World: North Korean Use of “Imagined Affinity” in the Socialist Globalization Project with Regard to Tanzania (1965–1970)...359-376 Tabqa: The Sister of the Aswan High Dam in Syria. How the Soviet Union Tried to Gain a Monopoly in Hydraulic Infrastructures in the Middle East...339-358 Risks and Opportunities: How East German Economists Reflected on Decolonization in the 1950s and 1960s...301-316 City of Red Tractors: Soviet Models and the Transfer of Agricultural Technology in Luoyang...317-338 Introduction...289-300 Inhaltsverzeichnis | Contents...285-286 Editorial...287-288
Engineering Yang-Lee anyons via Majorana bound states
Creators: name: Sanno, Takumi
name: Yamada, Masahiko G.
name: Mizushima, Takeshi
name: Fujimoto, Satoshi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We propose the platform of a Yang-Lee anyon system which is constructed from Majorana bound states in topological superconductors. Yang-Lee anyons, described by the non-unitary conformal field theory with the central charge $c=-22/5$, are non-unitary counterparts of Fibonacci anyons, obeying the same fusion rule, but exhibiting non-unitary non-Abelian braiding statistics. We consider a topological superconductor junction system coupled with dissipative electron baths, which realizes a non-Hermitian interacting Majorana system. Numerically estimating the central charge, we examine the condition that the non-Hermitian Majorana system can simulate the Ising spin model of the Yang-Lee edge singularity, and confirm that, by controlling model parameters in a feasible way, the Yang-Lee edge criticality is realized. On the basis of this scenario, we present the scheme for the fusion, measurement and braiding of Yang-Lee anyons in our proposed setup.
description: 12 pages, 11 figures
Additional file 3 of Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird
Creators: name: Mentesana, Lucia
name: Andersson, Martin N.
name: Casagrande, Stefania
name: Goymann, Wolfgang
name: Isaksson, Caroline
name: Hau, Michaela
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Ecology

description: Additional file 3. Results of linear mixed-effects models to test for relationships between yolk composition and phenotypic traits on nestling day 6.
Accelerating gravitational-wave parameterized tests of General Relativity using a multiband decomposition of likelihood
Creators: name: Adhikari, Naresh
name: Morisaki, Soichiro
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The detection of gravitational waves from compact binary coalescence (CBC) has allowed us to probe the strong-field dynamics of General Relativity (GR). Among various tests performed by the LIGO-Virgo-KAGRA collaboration are parameterized tests, where parameterized modifications to GR waveforms are introduced and constrained. This analysis typically requires the generation of more than millions of computationally expensive waveforms. The computational cost is higher for a longer signal, and current analyses take weeks-years to complete for a binary neutron star (BNS) signal. In this work, we present a technique to accelerate the parameterized tests using a multiband decomposition of likelihood, which was originally proposed to accelerate parameter estimation analyses of CBC signals assuming GR by one of the authors. We show that our technique speeds up the parameterized tests of a 1.4 Msun-1.4 Msun BNS signal by a factor of O(10) for a low-frequency cutoff of 20 Hz. We also verify the accuracy of our method using simulated signals and real data.
description: 12 pages, 8 figures
On the internal pollution mechanisms in the globular cluster NGC 6121 (M4): heavy-element abundances and AGB models
Creators: name: D'Orazi, Valentina
name: Campbell, Simon W.
name: Lugaro, Maria
name: Lattanzio, John C.
name: Pignatari, Marco
name: Carretta, Eugenio
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Globular clusters display significant variations in their light-element content, pointing to the existence of a second stellar generation formed from the ejecta of an earlier generation. The nature of these internal polluters is still a matter of debate: the two most popular scenarios indicate intermediate-mass AGB stars and fast rotating massive stars. Abundances determination for some key elements can help distinguish between these competitor candidates. We present in this paper Y abundances for a sample of 103 red giant branch stars in NGC 6121. Within measurement errors, we find that the [Y/Fe] is constant in this cluster contrary to a recent suggestion. For a subsample of six stars we also find [Rb/Fe] to be constant, consistent with previous studies showing no variation in other s-process elements. We also present a new set of stellar yields for intermediate-mass AGB stellar models of 5 and 6 solar masses, including heavy element s-process abundances. The uncertainties on the mass-loss rate, the mixing-length parameter, and the nuclear reaction rates have a major impact on the stellar abundances. Within the IM-AGB pollution scenario, the constant abundance of heavy elements inside the cluster requires a marginal s-process efficiency in IM-AGB stars. Such a constrain could still be satisfied by the present models assuming a stronger mass-loss rate. The uncertainties mentioned above are limiting the predictive power of intermediate-mass AGB models. For these reasons, at the moment we are not able to clearly rule out their role as main polluters of the second population stars in globular clusters.
description: Accepted for publication in MNRAS, 18 pages, 21 figures
Unusual Spin Polarization in the Chirality Induced Spin Selectivity
Creators: name: Wolf, Yotam
name: Liu, Yizhou
name: Xiao, Jiewen
name: Park, Noejung
name: Yan, Binghai
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Chirality-induced spin selectivity (CISS) refers to the fact that electrons get spin polarized after passing through organic chiral molecules in a nanoscale device. In CISS, chiral molecules are commonly believed to be a spin filter through which one favored spin transmits and the opposite spin gets reflected, i.e., transmitted and reflected electrons exhibit opposite spin polarization. In this work, we point out that such a spin filter scenario contradicts the principle that equilibrium spin current must vanish. Instead, we find that both transmitted and reflected electrons present the same type spin polarization, which is actually ubiquitous for a two-terminal device. More accurately, chiral molecules play the role of a spin polarizer rather than a spin filter. The direction of spin polarization is determined by the molecule chirality and the electron incident direction. And the magnitude of spin polarization replies on local spin-orbit coupling in the device. Our work brings a deeper understanding on CISS and interprets recent experiments, for example, the CISS-driven anomalous Hall effect.
description: 5 figures and supplementary information included
Additional file 4 of Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird
Creators: name: Mentesana, Lucia
name: Andersson, Martin N.
name: Casagrande, Stefania
name: Goymann, Wolfgang
name: Isaksson, Caroline
name: Hau, Michaela
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Ecology

description: Additional file 4. Results of linear mixed-effects models to test for relationships between yolk composition and phenotypic traits on day 12.
Neutron star deformation due to multipolar magnetic fields
Creators: name: Mastrano, Alpha
name: Lasky, Paul D.
name: Melatos, Andrew
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Certain multi-wavelength observations of neutron stars, such as intermittent radio emissions from rotation-powered pulsars beyond the pair-cascade death line, the pulse profile of the magnetar SGR 1900+14 after its 1998 August 27 giant flare, and X-ray spectral features of PSR J0821-4300 and SGR 0418+5729, suggest that the magnetic fields of non-accreting neutron stars are not purely dipolar and may contain higher-order multipoles. Here, we calculate the ellipticity of a non-barotropic neutron star with (i) a quadrupole poloidal-toroidal field, and (ii) a purely poloidal field containing arbitrary multipoles, deriving the relation between the ellipticity and the multipole amplitudes. We present, as a worked example, a purely poloidal field comprising dipole, quadrupole, and octupole components. We show the correlation between field energy and ellipticity for each multipole, that the l=4 multipole has the lowest energy, and that l=5 has the lowest ellipticity. We show how a mixed multipolar field creates an observationally testable mismatch between the principal axes of inertia (to be inferred from gravitational wave data) and the magnetic inclination angle. Strong quadrupole and octupole components (with amplitudes ~ 10^2 times higher than the dipole) in SGR 0418+5729 still yield ellipticity ~ 10^{-8}, consistent with current gravitational wave upper limits. The existence of higher multipoles in fast-rotating objects (e.g., newborn magnetars) has interesting implications for the braking law and hence phase tracking during coherent gravitational wave searches.
description: 13 pages, 5 figures. Monthly Notices of the Royal Astronomical Society 2013
title: Bayes-Statistik
Creators: name: Molenaar, Ivo W.
name: Lewis, Charles
Publisher: name: Universitätsbibliothek Mannheim
Year: 1996

description: Digitalisierte Ausgabe 2019. Gedruckt erschienen im Handbuch Quantitative Methoden (1996), hrsg. von Edgar Erdfelder, Rainer Mausfeld, Thorsten Meiser und Georg Rudinger, beim Beltz-Verlag (Weinheim), ISBN 3-621-27280-1.
An Agent-Based Fleet Management Model for First- and Last-Mile Services
Creators: name: Bhatnagar, Saumya
name: Rambha, Tarun
name: Ramadurai, Gitakrishnan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Multiagent Systems (cs.MA)
subject: FOS: Computer and information sciences

description: With the growth of cars and car-sharing applications, commuters in many cities, particularly developing countries, are shifting away from public transport. These shifts have affected two key stakeholders: transit operators and first- and last-mile (FLM) services. Although most cities continue to invest heavily in bus and metro projects to make public transit attractive, ridership in these systems has often failed to reach targeted levels. FLM service providers also experience lower demand and revenues in the wake of shifts to other means of transport. Effective FLM options are required to prevent this phenomenon and make public transport attractive for commuters. One possible solution is to forge partnerships between public transport and FLM providers that offer competitive joint mobility options. Such solutions require prudent allocation of supply and optimised strategies for FLM operations and ride-sharing. To this end, we build an agent- and event-based simulation model which captures interactions between passengers and FLM services using statecharts, vehicle routing models, and other trip matching rules. An optimisation model for allocating FLM vehicles at different transit stations is proposed to reduce unserved requests. Using real-world metro transit demand data from Bengaluru, India, the effectiveness of our approach in improving FLM connectivity and quantifying the benefits of sharing trips is demonstrated.
Bidirectional controlled teleportation by using 5-qubit states: A generalized view
Creators: name: Shukla, Chitra
name: Banerjee, Anindita
name: Pathak, Anirban
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Recently bidirectional controlled perfect teleportation using 5-qubit states are reported in (Int. J. Theor. Phys. (2013) DOI 10.1007/s10773-013-1484-8 and ibid, (2013) DOI 10.1007/s10773-012-1208-5). In this paper we have shown that there exists a class of 5-qubit quantum states that can be used for bidirectional controlled teleportation. Two out of the three reported cases are the special cases of the proposed class of 5-qubit quantum states and one of them is not strictly a case of controlled bidirectional quantum teleportation. Further, we have shown that one can in principle, construct infinitely many 5-qubit quantum states for this purpose. We have also shown that the idea can be extended to bidirectional controlled probabilistic teleportation. Some potential applications of the proposed scheme and its modified versions are also discussed in relation with the implementation of quantum remote control and quantum cryptography.
description: 4 tables and 5 pages
Additional file 5 of Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird
Creators: name: Mentesana, Lucia
name: Andersson, Martin N.
name: Casagrande, Stefania
name: Goymann, Wolfgang
name: Isaksson, Caroline
name: Hau, Michaela
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Ecology

description: Additional file 5. Results of linear mixed-effects models used to test for relationships between nestling tarsus length on days 6 and 12 and survival in the nest.
title: Outstanding chiroptical features in thin films of chiral π-conjugated oligomers: from synthesis to applications
Creators: name: Albano, Gianluigi
Publisher: name: Università di Pisa
Year: 2019

description: Chirality is gaining large interest in organic optoelectronics: first, it is a valid tool for controlling the supramolecular order of π-conjugated systems constituting the active layer of devices; secondly, it opens the way to innovative technological applications, like detecting or producing circularly polarized (CP) light. A current research goal is to obtain thin films of organic semiconductors with high discrimination of CP-light in absorption (electronic circular dichroism, ECD) or emission (circularly polarized luminescence, CPL). Chiral supramolecular architectures of π-conjugated systems could be the key to achieve this goal.In the present doctoral work, we developed a family of novel chiral π-conjugated oligomers functionalized with inexpensive alkyl chiral groups from natural sources, studying their ECD and CPL features in thin films. Since special care should be taken, in order to avoid the occurrence of false signals, here we provided practical tools for recognizing, quantifying and possible separating the main contributions of experimental ECD and CPL spectra. Although in general we observed a manifold of situations, thus revealing the central role of different local supramolecular structures (whose formation is strictly related to chemical structure, deposition technique and post-deposition operations), in some cases we discovered outstanding chiroptical features. Encouraged by promising results, for some of them we finally explored the application as active layers in circularly polarized organic light-emitting diode (CP-OLED) devices.
Heat pump driven entirely by quantum correlation
Creators: name: Holdsworth, Tharon
name: Kawai, Ryoichi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The second law of thermodynamics prohibits spontaneous heat from a cold to a hot body. However, it has been theoretically and experimentally shown that energy can flow from a cold to a hot body if the bodies are initially correlated. We investigated the \emph{anomalous energy exchange} between dissipation-less quantum systems that are initially entangled. Then, we extended this model to include dissipation demonstrating \emph{anomalous heat} from a cold to a hot body. Based on these models, we constructed a heat pump driven entirely by quantum correlation as fuel and investigated its performance with numerical simulations. Using the recently proposed definition of efficiency based on mutual information, the performance of the pump is found to be consistent with the second law of thermodynamics.
description: 9 pages, 7 figures
Coherent control of quantum topological states of light in Fock-state lattices
Creators: name: Deng, Jinfeng
name: Dong, Hang
name: Zhang, Chuanyu
name: Wu, Yaozu
name: Yuan, Jiale
name: Zhu, Xuhao
name: Jin, Feitong
name: Li, Hekang
name: Wang, Zhen
name: Cai, Han
name: Song, Chao
name: Wang, H.
name: You, J. Q.
name: Wang, Da-Wei
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Topological photonics provides a novel platform to explore topological physics beyond traditional electronic materials and stimulates promising applications in topologically protected light transport and lasers. Classical degrees of freedom such as polarizations and wavevectors are routinely used to synthesize topological light modes. Beyond the classical regime, inherent quantum nature of light gives birth to a wealth of fundamentally distinct topological states, which offer topological protection in quantum information processing. Here we implement such experiments on topological states of quantized light in a superconducting circuit, on which three resonators are tunably coupled to a gmon qubit. We construct one and two-dimensional Fock-state lattices where topological transport of zero-energy states, strain induced pseudo-Landau levels, valley Hall effect and Haldane chiral edge currents are demonstrated. Our study extends the topological states of light to the quantum regime, bridges topological phases of condensed matter physics with circuit quantum electrodynamics, and offers a new freedom in controlling the quantum states of multiple resonators.
description: 9 pages, 6 figures
title:  Study and optimization of the IXPE polarization-sensitive detectors
Creators: name: Di Lalla, Niccolò
Publisher: name: Università di Pisa
Year: 2019

description: Recently selected by NASA as the next SMall EXplorer (SMEX) mission for a launch in mid 2021, the Imaging X-ray Polarimetry Explorer (IXPE) will be the first mission entirely dedicated to X-ray polarimetry in the 2-10 keV energy band. At the heart of each of its three telescope systems is a Gas Pixel Detector (GPD), a polarization-sensitive imaging detector invented and developed in Italy. Thanks to its capabilities, IXPE will expand the X-ray view of the Universe, simultaneously adding polarization measurements (degree and angle) to the set of source properties currently measured in the X-ray band (spectrum, variability, and morphology).The main theme of this thesis is the study and the optimization of polarization-sensitive detectors that will be on-board IXPE. After a brief review of the X-ray polarimetry and a detailed presentation of the IXPE mission and its scientific goals, I focus on my research activity on the development of the Monte Carlo simulation of the GPD and the realization of a new simulation framework designed to produce fast and realistic IXPE observations.
Additional file 6 of Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird
Creators: name: Mentesana, Lucia
name: Andersson, Martin N.
name: Casagrande, Stefania
name: Goymann, Wolfgang
name: Isaksson, Caroline
name: Hau, Michaela
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Ecology

description: Additional file 6. Methods.
Self-sustained Clusters and Ergodicity Breaking in Spin Models
Creators: name: Yeung, Chi Ho
name: Saad, David
Publisher: name: arXiv
Year: 2013
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The emergence of self-sustained clusters and their role in ergodicity breaking is investigated in fully connected Ising and Sherrington-Kirkpatick (SK) models. The analysis reveals a clustering behavior at various parameter regimes, as well as yet unobserved phenomena such as the absence of non-trivial clusters in the Ising ferromagnetic and paramagnetic regimes, the formation of restricted spin clusters in SK spin glass and a first order phase transition in cluster sizes in the SK ferromagnet. The method could be adapted to investigate other spin models.
description: 4 pages, 4 figures + 21 pages of supplementary information
title: On Gromov's theory of multicomplexes: the original approach to bounded cohomology and simplicial volume
Creators: name: Moraschini, Marco
Publisher: name: Università di Pisa
Year: 2018

description: The simplicial volume is a homotopy invariant of manifolds introduced by Gromov in his pioneering paper "Volume and bounded cohomology". In order to study the main properties of simplicial volume, Gromov himself initiated the dual theory of bounded cohomology, which then developed into a very active and independent research field. Gromov's theory of bounded cohomology of topological spaces was based on the use of multicomplexes, which are simplicial structures that generalize simplicial complexes without allowing all the degeneracies appearing in simplicial sets. The first aim of this thesis is to lay the foundation of the theory of multicomplexes. After setting the main definitions, we construct the singular multicomplex K(X) associated to a topological space X, and we prove that the geometric realization of K(X) is homotopy equivalent to X for every CW complex X. Following Gromov, we introduce the notion of completeness, which, roughly speaking, translates into the context of multicomplexes the Kan condition for simplicial sets. We then develop the homotopy theory of complete multicomplexes, and we show that K(X) is complete for every CW complex X.In the second part of this thesis we apply the theory of multicomplexes to the study of the bounded cohomology of topological spaces. Our constructions and arguments culminate in the complete proofs of Gromov's Mapping Theorem (which implies in particular that the bounded cohomology of a space only depends on its fundamental group) and of Gromov's Vanishing Theorem, which ensures the vanishing of the simplicial volume of closed manifolds admitting an amenable cover of small multiplicity. The third and last part of the thesis is devoted to the study of locally finite chains on non-compact spaces, hence to the simplicial volume of open manifolds. We expand some ideas of Gromov to provide complete proofs of a criterion for the vanishing and a criterion for the finiteness of the simplicial volume of open manifolds. As a by-product of theseresults, we prove a criterion for the l1-invisibility of closed manifolds in terms of amenable covers. As an application, we give the first complete proof of the vanishing of the simplicial volume of the product of three open manifolds.
A spectroscopic and proper motion search of Sloan digital Sky Survey: red subdwarfs in binary systems
Creators: name: Zhang, Z. H.
name: Pinfield, D. J.
name: Burningham, B.
name: Jones, H. R. A.
name: Galvez-Ortiz, M. C.
name: Catalan, S.
name: Smart, R. L.
name: Lepine, S.
name: Clarke, J. R. A.
name: Pavlenko, Ya. V.
name: Murray, D. N.
name: Kuznetsov, M. K.
name: Day-Jones, A. C.
name: Gomes, J.
name: Marocco, F.
name: Sipocz, B.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Red subdwarfs in binary systems are crucial for both model calibration and spectral classification. We search for red subdwarfs in binary systems from a sample of high proper motion objects with Sloan digital Sky Survey spectroscopy. We present here discoveries from this search, as well as highlight several additional objects of interest. We find 30 red subdwarfs in wide binary systems including: two with spectral type of esdM5.5, 6 companions to white dwarfs and 3 carbon enhanced red subdwarfs with normal red subdwarf companions. 15 red subdwarfs in our sample are partially resolved close binary systems. With this binary sample, we estimate the low limit of the red subdwarf binary fraction of ~ 10%. We find that the binary fraction goes down with decreasing masses and metallicities of red subdwarfs. A spectroscopic esdK7 subdwarf + white dwarf binary candidate is also reported. 30 new M subdwarfs have spectral type of >= M6 in our sample. We also derive relationships between spectral types and absolute magnitudes in the optical and near-infrared for M and L subdwarfs, and we present an M subdwarf sample with measured U, V, W space velocities.
description: 26 pages, 19 figures
Additional file 7 of Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird
Creators: name: Mentesana, Lucia
name: Andersson, Martin N.
name: Casagrande, Stefania
name: Goymann, Wolfgang
name: Isaksson, Caroline
name: Hau, Michaela
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Ecology

description: Additional file 7. Linear models testing for differences in yolk composition between years.
A Brownian cyclic engine operating in a viscoelastic active suspension
Creators: name: Guevara-Valadez, Carlos Antonio
name: Marathe, Rahul
name: Gomez-Solano, Juan Ruben
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate a model for a Stirling-like engine consisting of a passive Brownian particle confined by a harmonic potential and interacting with a suspension of active Brownian particles that self-propel in a viscous solvent, which cyclically operates under isothermal conditions by means of temporal variations of the trap stiffness and the self-propulsion speed of the active particles. We derive an effective stochastic equation of motion of the trapped Brownian particle, which includes a friction memory kernel as well as thermal and active fluctuating forces due to its coupling with the active suspension, from which we analytically compute the efficiency of the engine in the quasi-static limit. We find that, on average, the engine is capable to produce mechanical work with an efficiency that depends on the interplay between the different time-scales of the system, where the general effect of the ensuing viscoelasticity of the active suspension is to reduce the quasi-static efficiency of the Brownian engine, as compared to the case of a system with instantaneous friction. Nevertheless, there are regions in the parameters space of the system where such memory effects are negligible in the performance of the engine, thus effectively behaving as in contact with an inert viscous bath working at two different temperatures related to the propulsion speed of the active particles.
description: 17 pages, 6 figures, submitted
title: Retrogade approach to dissect the mouse connectome and generation of new Rabies Virus tools for functionale analysis of synaptically connected neurons
Creators: name: Barsotti, Noemi
Publisher: name: Università di Pisa
Year: 2018

description: Connectomics research is putting in action a comprehensive analysis to dissect the anatomy of brain circuits and axonal architecture to better understand the neural functioning. Since the dawn of neuroanatomy research, viral tracers have been useful tools to investigate the neural connections. An excellent viral tracer is Rabies Virus (RV), that, thanks to its properties to specifically infect at pre-synaptic terminal can univocally link a target brain area to the relative synaptically connected neurons. However, to take a step forward in understanding neural functions, directly manipulation of the neural genome is required.Here, I describe different projects I worked on during my PhD course that took advantage of RV.First, I joined a project that resulted in drawing a map of serotonergic innervation to the rostral brain. We identified a serotonergic subpopulation characterized by the wiring transmission modality.Second, in collaboration with the Italian Institute of Technology of Rovereto, we analysed the cortical connectivity in the Cntnap2 autism spectrum disorder mouse model. The rsfMRI analysis highlighted an asynchronous activity in the cingulate cortex (CG) that could be ascribed to a reduced PFC-projecting subpopulation in CG identified by means of RV-based retrograde tracing. Third, in order to allow the direct manipulation of the genome of retrograded neurons I developed RV variants expressing iCre and Flpe recombinase enzymes which mediate somatic DNA recombination in presence of specific sites.Fourth, I generated a new non-cytotoxic recombinase-expressing RV tools that allow to manipulate the genome of infected subpopulation and to overcome the time limits of RV allowing long-term experiments.
Padé Approximation and Hypergeometric Functions: A Missing Link with the Spectrum of Delay-Differential Equations
Creators: name: Boussaada, Islam
name: Mazanti, Guilherme
name: Niculescu, Silviu-Iulian
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optimization and Control (math.OC)
subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics

description: It is well known that rational approximation theory involves degenerate hypergeometric functions and, in particular, the Padé approximation of the exponential function is closely related to Kummer hypergeometric functions. Recently, in the context of the study of the exponential stability of the trivial solution of delay-differential equations, a new link between the degenerate hypergeometric function and the zeros distribution of the characteristic function associated with linear delay-differential equations was emphasized. Such a link allowed the characterization of a property of time-delay systems known as multiplicity-induced-dominancy (MID), which opened a new direction in designing low-complexity controllers for time-delay systems by using a partial pole placement idea. Thanks to their relations to hypergeometric functions, we explore in this paper links between the spectrum of delay-differential equations and Padé approximations of the exponential function. This note exploits and further comments recent results from [I. Boussaada, G. Mazanti and S-I. Niculescu. 2022, Comptes Rendus. Mathématique, arXiv:2107.11363] and [I. Boussaada, G. Mazanti and S-I. Niculescu. 2022, Bulletin des Sciences Mathématiques, arXiv:2106.03378].