cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
From correlation functions to scattering amplitudes
Creators: name: Eden, Burkhard
name: Korchemsky, Gregory P.
name: Sokatchev, Emery
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the correlators of half-BPS protected operators in N=4 super-Yang-Mills theory, in the limit where the positions of the adjacent operators become light-like separated. We compute the loop corrections by means of Lagrangian insertions. The divergences resulting from the light-cone limit are regularized by changing the dimension of the integration measure over the insertion points. Switching from coordinates to dual momenta, we show that the logarithm of the correlator is identical with twice the logarithm of the matching MHV gluon scattering amplitude. We present a number of examples of this new relation, at one and two loops.
description: typos corrected, references added
Defining the role of partially covalent weak interactions in chemical reactions
Creators: name: Tong, Xing
Publisher: name: University of British Columbia
Year: 2023

description: Weak interactions, commonly known as secondary bond interactions (SBIs), have received far less attention than their stronger counterparts (i.e., primary bonds, e.g., ionic, metallic, and covalent bonds). The most mainstream perspective is that those interactions are induced by the attraction between partially positive and partially negative areas on molecular surfaces. This electrostatics-driven model has been widely accepted as it is straightforward, intuitive, and widely applicable; however, more and more computational and experimental discoveries have thrown this “simple and practical” theory into question. Other quantum chemical effects like charge transfer cannot be ignored if a generalized picture of weak interactions is required. Due to the relatively weak bond strengths, it is often difficult to study weak interactions exclusively and accurately. With synchrotron X-ray absorption spectroscopy (XAS) in combination with different computational methods, the nature of two common weak interactions (i.e., halogen bonding XB and chalcogen bonding ChB) has been comprehensively investigated. To begin with, two types of model systems (i.e., hypervalent halogen salts and bis-triazole-pyridinium series) were chosen to study the degree of charge transfer in XB and ChB. These studies have given evidence for a substantial degree of covalent contribution in both XB and ChB interactions. The relevance of such interactions in modulating chemical processes has also been explored. For example, the significance of the charge transfer component in XB was confirmed in a catalyzed Ritter-like process (carbon-halogen bond cleavage). We have further demonstrated the important role of ChB in processes ranging from petroleum-coke modification to pharmaceutical drug synthesis. The obtained data has shown that both XBs and ChBs should be considered as partially covalent interactions and the covalent contributions can be tuned by the properties of involved electron donor/acceptor pairs. Those results are intended for a more rational design of the weak-interaction-assisted systems in many fields, such as catalysis, synthesis, anion recognition, and molecular electronics.
Experimental scaling of the scrape-off layer particle flux width by outboard divertor Langmuir probes with favorable Bt configuration on EAST
Creators: name: Liu, X.
name: Meng, L. Y.
name: Xu, J. C.
name: Wang, L.
name: Li, J.
name: Team, the EAST
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The scrape-off layer (SOL) power width (λ_q) is important for predicting the heat load on divertor targets for future magnetically confined devices. Currently, the underlying physics for λ_q scaling is not fully understood. This paper extends the previous inboard SOL particle flux width (λ_{js}) scaling [Liu et al 2019 Plasma Phys. Control. Fusion 61 045001] to the outboard side in EAST, which can provide more experimental evidence for λ_q study. A systematic method has been developed to correct the less reliable upper outer (UO) divertor Langmuir probe (Div-LP) measurements with their more reliable neighboring measurements to reduce the measurement uncertainty of λ_js. For the discharges with the favorable Bt and upper single null configurations in the 2019 experiment campaign, about 260 discharges have been selected by certain criteria to ensure good λ_js measurements. Three H-mode, L-mode, and Ohmic databases have been constructed and are used for λ_js scalings. It is found that the outboard λ_js for the H-mode and L-mode plasmas scales as, λ_(js,UO)=1.52(W_{MHD}/n_e)^(-0.61) P_{tot}^0.19, where W_{MHD} is the stored energy, n_e is the line-averaged density, and P_{tot} is the total input power. This scaling is similar to the inboard λ_js scaling except for the scaling amplitude that is probably due the triangularity. The repeatable scaling dependence on W_{MHD}/n_e confirms the reliability of this dependence even though the regression quality is relatively poor. It is also discussed that the solely scaling of λ_q/λ_{js} on Bp is not enough to include all the physics of SOL heat transports.
description: 14 pages, 7 figures, 4 tables, Nucl. Fusion (2023)
Asymptotic flatness at null infinity in arbitrary dimensions
Creators: name: Tanabe, Kentaro
name: Kinoshita, Shunichiro
name: Shiromizu, Tetsuya
Publisher: name: arXiv
Year: 2011
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We define the asymptotic flatness and discuss asymptotic symmetry at null infinity in arbitrary dimensions using the Bondi coordinates. To define the asymptotic flatness, we solve the Einstein equations and look at the asymptotic behavior of gravitational fields. Then we show the asymptotic symmetry and the Bondi mass loss law with the well-defined definition.
description: 12 pages, published version in PRD
Geometry parameter estimation for sparse X-ray log imaging
Creators: name: Senchukova, Angelina
name: Suuronen, Jarkko
name: Heikkinen, Jere
name: Roininen, Lassi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Image and Video Processing (eess.IV)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: We consider geometry parameter estimation in industrial sawmill fan-beam X-ray tomography. In such industrial settings, scanners do not always allow identification of the location of the source-detector pair, which creates the issue of unknown geometry. This work considers an approach for geometry estimation based on the calibration object. We parametrise the geometry using a set of 5 parameters. To estimate the geometry parameters, we calculate the maximum cross-correlation between a known-sized calibration object image and its filtered backprojection reconstruction and use differential evolution as an optimiser. The approach allows estimating geometry parameters from full-angle measurements as well as from sparse measurements. We show numerically that different sets of parameters can be used for artefact-free reconstruction. We deploy Bayesian inversion with first-order isotropic Cauchy difference priors for reconstruction of synthetic and real sawmill data with a very low number of measurements.
Combustion characteristics of compression ignition engine operating on rapeseed oil-diesel fuel blends
Creators: name: Čedík, J.
name: Pexa, M.
name: Mader, D.
name: Pražan, R.
Publisher: name: Agronomy Research
Year: 2019
Subjects: biofuels
cylinder pressure
heat release rate
engine efficiency
article

description: The effect of biofuels on the operational parameters of the combustion engines, such as performance parameters or emission production, are monitored often. These changes are, however, based on the effect of biofuels on the course of combustion pressure inside the combustion chamber. The contribution deals with the effect of rapeseed oil-diesel fuel blends on the combustion characteristics of turbocharged compression ignition engine. The course of cylinder pressure was monitored and analysed and heat release rate was calculated. The brake specific fuel consumption, indicated and brake thermal efficiency were calculated and evaluated, in-cylinder temperature and ignition delay were also evaluated. As a test fuels a 5% and 20% concentrations of rapeseed oil in diesel fuel were selected while 100% diesel fuel was used as a reference. Turbocharged CI engine Zetor 1204 located in the tractor Zetor Forterra 8642 was used for measurement. During measurement the rotation speed of the engine was kept constant at approx. 1950 min-1 and the load of the engine was selected at approx. 20, 60, 80 and 100%. The results showed decreased cylinder peak pressure, decreased intensity of heat release rate and earlier end of combustion in all tested loads for both tested fuel blends in comparison with diesel fuel, while the lowest peak cylinder pressure was reached using fuel with 5% rapeseed oil. Fuel with 5% rapeseed oil also showed highest indicated efficiency. Ignition delay was found shorter with both of the blended fuels in comparison with diesel fuel.
Autonomous photovoltaic system for night-time lighting in the stable
Creators: name: Dang, M-Q.
name: Šafránková, J.
name: Libra, M.
name: Poulek, V.
name: Kouřím, P.
name: Sedláček, J.
Publisher: name: Agronomy Research
Year: 2019
Subjects: photovoltaics
off-grid PV system
LED
article

description: Autonomous photovoltaic (PV) systems are suitable, for example, for powering various appliances or scientific instruments in the field, for automatic data collection, for signaling, etc. At the Czech University of Life Sciences Prague, we have designed an experimental autonomous PV system designed for night-time lighting for orientating in a stable for horses. The article describes the construction of a PV system with a PV panel rated at 170 Wp, with a lead-acid accumulator and a 1,5 W LED light source. The data collection was automated. The data evaluation shows that during the whole year, the PV system has been recharged and there was no lighting failure. The paper also presents important measured characteristics.
Stochastic maximal $L^p$-regularity
Creators: name: van Neerven, Jan
name: Veraar, Mark
name: Weis, Lutz
Publisher: name: arXiv
Year: 2010
Subjects: subject: Probability (math.PR)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics

description: In this article we prove a maximal $L^p$-regularity result for stochastic convolutions, which extends Krylov's basic mixed $L^p(L^q)$-inequality for the Laplace operator on ${\mathbb{R}}^d$ to large classes of elliptic operators, both on ${\mathbb{R}}^d$ and on bounded domains in ${\mathbb{R}}^d$ with various boundary conditions. Our method of proof is based on McIntosh's $H^{\infty}$-functional calculus, $R$-boundedness techniques and sharp $L^p(L^q)$-square function estimates for stochastic integrals in $L^q$-spaces. Under an additional invertibility assumption on $A$, a maximal space--time $L^p$-regularity result is obtained as well.
description: Published in at http://dx.doi.org/10.1214/10-AOP626 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Bugs as Features (Part I): Concepts and Foundations for the Compositional Data Analysis of the Microbiome-Gut-Brain Axis
Creators: name: Bastiaanssen, Thomaz F. S.
name: Quinn, Thomas P.
name: Loughman, Amy
Publisher: name: arXiv
Year: 2022
Subjects: subject: Genomics (q-bio.GN)
subject: Applications (stat.AP)
subject: FOS: Biological sciences
subject: FOS: Computer and information sciences

description: There has been a growing acknowledgement of the involvement of the gut microbiome - the collection of microbes that reside in our gut - in regulating our mood and behaviour. This phenomenon is referred to as the microbiome-gut-brain axis. While our techniques to measure the presence and abundance of these microbes have been steadily improving, the analysis of microbiome data is non-trivial.
 Here, we present a perspective on the concepts and foundations of data analysis and interpretation of microbiome experiments with a focus on the microbiome-gut-brain axis domain. We give an overview of foundational considerations prior to commencing analysis alongside the core microbiome analysis approaches of alpha diversity, beta diversity, differential feature abundance and functional inference. We emphasize the compositional data analysis (CoDA) paradigm.
 Further, this perspective features an extensive and heavily annotated microbiome analysis in R in the supplementary materials, as a resource for new and experienced bioinformaticians alike.
description: For main text: 23 pages, 3 figures; for supplementary demonstration analysis: 31 pages and 12 figures. Supplementary demonstration analysis generated using Rmarkdown by Thomaz F. S. Bastiaanssen. Part I of a two-part piece
Winter rye grain quality of hybrid and population cultivars
Creators: name: Linina, A.
name: Kunkulberga, D.
name: Kronberga, A.
name: Locmele, I.
Publisher: name: Agronomy Research
Year: 2019
Subjects: winter rye
protein content
starch content
Hagberg falling number
article

description: Rye (Secale cereale L.) is an important European crop used for food that is grown primarily in Eastern, Central and Northern Europe. Consuming rye grain products provides a rich source of dietary fibre as well as several bioactive compounds with potentially positive health implications. The goal of the research was to compare the rye grain quality of hybrid and population cultivars. A field trial was carried out in Priekuli Research Centre, Institute of Agricultural Resourses and Economic (in Latvia) during a three-year period: 2014/2015, 2015/2016, and 2016/2017. The trial included population winter rye cultivars ‘Kaupo’, ‘Amilo’, ‘Dankowskie Amber’ and hybrid rye cultivars ‘Brasetto’, ‘Su Drive’, ‘Su Mephisto’. Rye grain quality indices were analysed at Latvia University of Life Sciences and Technologies, in Grain and Seed Research laboratory. Average data in our investigation (three years) show that cultivar, crop-year (weather conditions) and cultivar×crop-year interaction significantly (P < 0.05) affected rye grain protein content, starch content and Hagberg falling number. A significant negative correlation was found between protein content and starch content r = -0.937 (population cultivars grain), r = -0.944 (hybrid cultivars grain), medium strong negative correlation was found between protein content and falling number, respective r = -0.549 and r = -0.573. Differences between hybrid cultivar grain protein content, falling number and starch content comparing with population cultivar grains were not observed. The results of the current research show that the quality of all the studied cultivars meets the requirements for high-grade rye grains for food consumption.
Near-critical fluctuations and cytoskeleton-assisted phase separation lead to subdiffusion in cell membranes
Creators: name: Ehrig, Jens
name: Petrov, Eugene P.
name: Schwille, Petra
Publisher: name: arXiv
Year: 2010
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We address the relationship between membrane microheterogeneity and anomalous subdiffusion in cell membranes by carrying out Monte Carlo simulations of two-component lipid membranes. We find that near-critical fluctuations in the membrane lead to transient subdiffusion, while membrane-cytoskeleton interaction strongly affects phase separation, enhances subdiffusion, and eventually leads to hop diffusion of lipids. Thus, we present a minimum realistic model for membrane rafts showing the features of both microscopic phase separation and subdiffusion.
description: 21 pages, 5 figures; Supporting Material 5 pages, 1 figure, 1 table
Accelerated technology of rye bread with improved quality and increased nutritional value
Creators: name: Dubrovskaya, N.
name: Savkina, O.
name: Kuznetsova, L.
name: Parakhina, O.
name: Usova, L.
Publisher: name: Agronomy Research
Year: 2019
Subjects: bread
rye
rowan powder
article

description: Accelerated bakery technologies do not always ensure high bread quality. The taste and smell of bread is less pronounced when compared with the traditionally prepared bread and it is quickly subjected to microbial spoilage. The aim of the research was to develop an improved composite mixture for the accelerated technology of rye bread, which would improve its quality, nutritional value, extend shelf life and microbiological stability. Rowan powder (botanical species Sorbus aucuparia) as unconventional raw ingredients of high nutritional and biological value was used. Rowan powder has high acidity (40 degrees or 5.7% in terms of malic acid) and contains a wide range of organic acids, including volatile acids (2–3%) and preservative acids (such as sorbic acid), as well as other micro- and macronutrients. New acidifying additive with rowan powder was created. The optimal dosage of rowan powder in the new acidifying additive by 13% per 100 kg of flour allows bread making with higher specific volume, acidity and porosity of the crumb compared with the control sample. The research proves that rowan powder usage in the accelerated bread technology improves its organoleptic and physico-chemical indicators and also increases the content of dietary fiber, vitamins and minerals. The content of fibers in custard bread with rowan powder was 1.85 times higher than in the control sample. The rowan powder usage has a positive effect on the preservation of bread freshness during its storage. The rowan powder usage slows down the custard bread mould disease.
Selección de personal en la era digital: criterio , predictores y métodos
Creators: name: Ramos-Villagrasa, Pedro J.
Publisher: name: Zenodo
Year: 2023
Subjects: selección de personal

description: Conferencia invitada impartida para miembros del Departamento de Psicología Social, del Trabajo y Diferencial el día 28 de marzo de 2023. En ella se repasan algunos temas emergentes dentro de la selección de personal, con especial atención a los avances derivados de la digitalización de los Recursos Humanos.
State sampling dependence of the Hopfield network inference
Creators: name: Huang, Haiping
Publisher: name: arXiv
Year: 2011
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: The fully connected Hopfield network is inferred based on observed magnetizations and pairwise correlations. We present the system in the glassy phase with low temperature and high memory load. We find that the inference error is very sensitive to the form of state sampling. When a single state is sampled to compute magnetizations and correlations, the inference error is almost indistinguishable irrespective of the sampled state. However, the error can be greatly reduced if the data is collected with state transitions. Our result holds for different disorder samples and accounts for the previously observed large fluctuations of inference error at low temperatures.
description: 4 pages, 1 figure, further discussions added and relevant references added
Hydrodynamic simulations of directed flow for light hadrons in Au+Au and isobar collisions $\sqrt{s_{\textrm{NN}}}=$ 200 GeV
Creators: name: Jing, Jing
name: Jiang, Ze-Fang
name: Yang, C. B.
name: Zhang, Ben-Wei
Publisher: name: arXiv
Year: 2022
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Using a (3+1)-D hydrodynamic model CLVisc, we study the directed flow ($v_{1}$) of light hadrons produced in Au+Au, Ru+Ru and Zr+Zr collisions at $\sqrt{s_{\textrm{NN}}}=$ 200 GeV. The evolution of tilted energy density, pressure gradient and radial flow along the $x$-direction are systematically investigated. Counter-clockwise tilt of initial fireball is shown to be a vital source of the directed flow for final light hadrons. A good description of directed flow is provided for light hadrons in central and mid-central Au+Au and isobar collisions at RHIC. Our numerical results show a clear system size dependence for light hadron $v_{1}$ across different collision systems. We further study the effect of nuclear structure on the directed flow and find that the $v_{1}$ for light hadrons is insensitive to the nuclei with quadrupole deformation.
description: 11 pages, 9 figures, 3 tables, published in Chin. Phys. C
Iron(II) coordination compounds with improved octahedral character and photophysical properties for solar energy harvesting
Creators: name: Overney-Ragan, Tobias
Publisher: name: University of British Columbia
Year: 2023

description: A series of novel Fe(II) coordination complexes were synthesized and investigated for enhanced structural and photophysical properties. Spacer sulfur atoms were introduced in a terpyridine ligand motif, and a near-perfect octahedral coordination environment resulted in the stabilization of the spin-crossover transition between LS and HS in the crystallographic state. Two nonequal Fe(II) centers were contained within the unit cell of the homoleptic complex Fe(TPS)₂, with bond lengths unambiguously attributed to different spin-states on the nonequal Fe(II) centers within the same crystal at 100 K, and a gradual increase to LS character at higher temperatures. Two pincer-type ligands were synthesized in an effort to improve the excited-state lifetime decay pathway in Fe(II) complexes. Both ligand motifs incorporated a coordinating amido bridging moiety, which resulted in panchromatic light absorption, with charge-transfer bands in the far-vis and NIR regions. Furthermore, computational calculations confirmed that both complexes’ HOMOs are composed of contributions from both metal and ligand orbitals, as opposed to metal-centered as in most classical complexes. A pincer ligand with flanking NHCs was successful in raising the ⁵MC energy to a noncompetitive height with respect to the ³MLCT state, resulting in deactivation of the excited state via the ³MC state. When the NHCs were substituted for pyridines in the second ligand framework, the decay pathway proceeded through the ³MLCT to the ³MC and ⁵MC states. In both cases, the excited state ³MLCT decays were more than an order of magnitude larger than those in the prototypical comparison complex, Fe(tpy)₂.
Infrared Regularization and Finite Size Dynamics of Entanglement Entropy in Schwarzschild Black Hole
Creators: name: Ageev, D. S.
name: Aref'eva, I. Ya.
name: Belokon, A. I.
name: Ermakov, A. V.
name: Pushkarev, V. V.
name: Rusalev, T. A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper, infrared regularization of semi-infinite entangling regions and island formation for regions of finite size in the eternal Schwarzschild black hole are considered. We analyze whether the complementarity property and pure state condition of entanglement entropy can be preserved in the given approximation. We propose a special regularization that satisfies these two properties. With regard to entangling regions of finite size, we derive two fundamental types of them, which we call "mirror-symmetric" (MS) and "asymmetric" (AS). For MS regions, we discover a discontinuous evolution of the entanglement entropy of Hawking radiation due to finite lifetime of the island. The entanglement entropy of matter for semi-infinite regions in two-sided Schwarzschild black hole does not follow the Page curve. The lifetime of AS regions is bounded from above due to the phenomenon that we call "Cauchy surface breaking". Shortly before this breaking, the island configuration becomes non-symmetric. For both types of finite regions, there is a critical size, below which the island never dominates. For regions smaller than some other critical size, the island does not emerge. Finally, we show that the island prescription does not help to solve the information paradox for certain finite regions.
description: v1: 55 pages, 19 figures; v2: 57 pages, 19 figures, references added, Sec. 5 presentation improved; v3: 22 pages, 24 figures, title changed, presentation improved, details added, references added, typos corrected, style changed; v4: 22 pages, 24 figures, notations clarified; v5: 22 pages, 23 figures, one figure removed, some statements have been slightly corrected, new links have been added
Modelling Travel Demand: A Disaggregate Behavioral Approach Issues and Applications
Creators: name: Stopher, P.R.
name: Lisco, T.E.
name: Stopher, P.R.
name: Lisco, T.E.
Publisher: name: Unknown
Year: 1970
Subjects: Public Economics

description: Presented at the 11th Transportation Research Forum meeting, Oct. 22-24, 1970, New Orleans, LA
Dial-A-Bus Revenue Potential
Creators: name: Stafford, Joseph H.
name: Neufville, Richard De
name: Plourde, Rodney
name: Stafford, Joseph H.
name: Neufville, Richard De
name: Plourde, Rodney
Publisher: name: Unknown
Year: 1970
Subjects: Public Economics

description: Presented at the 11th Transportation Research Forum meeting, Oct. 22-24, 1970, New Orleans, LA
Relating quarks and leptons without grand-unification
Creators: name: Morisi, S.
name: Peinado, E.
name: Shimizu, Yusuke
name: Valle, J. W. F.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In combination with supersymmetry, flavor symmetry may relate quarks with leptons, even in the absence of a grand-unification group. We propose an SU(3)xSU(2)xU(1) model where both supersymmetry and the assumed A4 flavor symmetries are softly broken, reproducing well the observed fermion mass hierarchies and predicting: (i) a relation between down-type quarks and charged lepton masses, and (ii) a correlation between the Cabibbo angle in the quark sector, and the reactor angle characterizing CP violation in neutrino oscillations.
description: 4 pages, 2 figures, version published in PRD
Deterministic Free-Propagating Photonic Qubits with Negative Wigner Functions
Creators: name: Magro, Valentin
name: Vaneecloo, Julien
name: Garcia, Sébastien
name: Ourjoumtsev, Alexei
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: Engineering quantum states of free-propagating light is of paramount importance for quantum technologies. Coherent states ubiquitous in classical and quantum communications, squeezed states used in quantum sensing, and even highly-entangled cluster states studied in the context of quantum computing can be produced deterministically, but they obey quasi-classical optical field statistics described by Gaussian, positive Wigner functions. Fully harnessing the potential of many quantum engineering protocols requires using non-Gaussian Wigner-negative states, so far produced using intrinsically probabilistic methods. Here we describe the first fully deterministic preparation of non-Gaussian Wigner-negative free-propagating states of light, obtained by mapping the internal state of an intracavity Rydberg superatom onto an optical qubit encoded as a superposition of 0 and 1 photons. This approach allows us to reach a 60% photon generation efficiency in a well-controlled spatio-temporal mode, while maintaining a strong photon antibunching. By changing the qubit rotation angle, we observe an evolution from quadrature squeezing to Wigner negativity. Our experiment sets this new technique as a viable method to deterministically generate non-Gaussian photonic resources, lifting several major roadblocks in optical quantum engineering.
On belief propagation guided decimation for random k-SAT
Creators: name: Coja-Oghlan, Amin
Publisher: name: arXiv
Year: 2010
Subjects: subject: Combinatorics (math.CO)
subject: Discrete Mathematics (cs.DM)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: F.2.2
subject: 68R01

description: Let F be a uniformly distributed random k-SAT formula with n variables and m clauses. Non-constructive arguments show that F is satisfiable for clause/variable ratios m/n< r(k)~2^k ln 2 with high probability. Yet no efficient algorithm is know to find a satisfying assignment for densities as low as m/n r(k).ln(k)/k with a non-vanishing probability. In fact, the density m/n r(k).ln(k)/k seems to form a barrier for a broad class of local search algorithms. One of the very few algorithms that plausibly seemed capable of breaking this barrier is a message passing algorithm called Belief Propagation Guided Decimation. It was put forward on the basis of deep but non-rigorous statistical mechanics considerations. Experiments conducted for k=3,4,5 suggested that the algorithm might succeed for densities very close to r_k. Furnishing the first rigorous analysis of BP decimation, the present paper shows that the algorithm fails to find a satisfying assignment already for m/n>c.r(k)/k, for a constant c>0 (independent of k).
Dynamical Signatures of Symmetry Broken and Liquid Phases in an $S=1/2$ Heisenberg Antiferromagnet on the Triangular Lattice
Creators: name: Drescher, Markus
name: Vanderstraeten, Laurens
name: Moessner, Roderich
name: Pollmann, Frank
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present the dynamical spin structure factor of the antiferromagnetic spin-$\frac{1}{2}$ $J_1-J_2$ Heisenberg model on a triangular lattice obtained from large-scale matrix-product state simulations. The high frustration due to the combination of antiferromagnetic nearest and next-to-nearest neighbour interactions yields a rich phase diagram. We resolve the low-energy excitations both in the $120^{\circ}$-ordered phase and in the putative spin liquid phase at $J_2/J_1 = 0.125$. In the ordered phase, we observe an avoided decay of the lowest magnon-branch, demonstrating the robustness of this phenomenon in the presence of gapless excitations. Our findings in the spin-liquid phase chime with the field-theoretical predictions for a gapless Dirac spin liquid, in particular the picture of low-lying monopole excitations at the corners of the Brillouin zone. We comment on possible practical difficulties of distinguishing proximate liquid and solid phases based on the dynamical structure factor.
Evaluation of retention stresses of prestressing bars of a concrete ribbed panel from agricultural building after 20 years of service
Creators: name: Kiviste, Mihkel
name: Lille, Harri
name: Linnus, Lauri
name: Halgma, Riho
Publisher: name: Agronomy Research
Year: 2019
Subjects: retention stress
precast
prestressed
concrete
ribbed panel
article

description: In Estonian agricultural buildings there exist a lot of precast concrete load-bearing structures, which were manufactured in the 1970s and 80s. By now, some of these are rather near for reaching their designed service life. 20 years old prestressed concrete ribbed ceiling panels (type PNS-12) with the dimensions of 6 m (length) by 1.5 m (width) from an existing agricultural building (pigsty) are the subject of current study. The objective of current study was to evaluate the retention stress of prestressing bars (PSBs) of a ribbed panel PNS-12. In other words the purpose was to find out how much of the factory-issued initial prestress was left at the PSBs after 20 years of service. As a novel application in civil engineering strain gauges were applied in the evaluation of retention stress of PSBs in current study. The active strain gauges were glued to the opposite sides of PSBs at the middle-span of the ribbed panel, dummy gauges were glued to the unloaded steel slab. Strain gauges were connected to the half-bridge and measured with strain indicator and recorded. Retention stresses were calculated using the Hooke’s law through the measured strains and elastic modulus of steel. Elastic modulus of PSBs was also measured using the universal testing machine Instron 3369 and software Bluehill 2, based on two standards. The results demonstrated about 20.8% and 10.0% of retention stress of PSBs, respectively. The possible errors created by different aspects in experiment are also discussed.
Estimation of circular statistics in the presence of measurement bias
Creators: name: Alsammani, Abdallah
name: Stacey, William C.
name: Gliske, Stephen V.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantitative Methods (q-bio.QM)
subject: Methodology (stat.ME)
subject: FOS: Biological sciences
subject: FOS: Computer and information sciences
subject: 62H11, 62P10, 65M15, 65R32, 92C55

description: Background and objective. Circular statistics and Rayleigh tests are important tools for analyzing the occurrence of cyclic events. However, current methods fail in the presence of measurement bias, such as incomplete or otherwise non-uniform sampling. Consider, for example, studying 24-cyclicity but having data not recorded uniformly over the full 24-hour cycle. The objective of this paper is to present a method to estimate circular statistics and their statistical significance even in this circumstance.
 Methods. We present our objective as a special case of a more general problem: estimating probability distributions in the context of imperfect measurements, a highly studied problem in high energy physics. Our solution combines 1) existing approaches that estimate the measurement process via numeric simulation and 2) innovative use of linear parametrizations of the underlying distributions. We compute the estimation error for several toy examples as well as a real-world example: analyzing the 24-hour cyclicity of an electrographic biomarker of epileptic tissue controlled for state of vigilance.
 Results. Our method shows low estimation error. In a real-world example, we observed the corrected moments had a root mean square residual less than 0.007. We additionally found that, even with unfolding, Rayleigh test statistics still often underestimate the p-values (and thus overestimate statistical significance) in the presence of non-uniform sampling. Numerical estimation of statistical significance, as described herein, is thus preferable.
 Conclusions. The presented methods provide a robust solution to addressing incomplete or otherwise non-uniform sampling. The general method presented is also applicable to a wider set of analyses involving estimation of the true probability distribution adjusted for imperfect measurement processes.
The effect of ageing on chosen quality characteristics of skeletal muscles of Aberdeen Angus bulls
Creators: name: Soidla, Riina
name: Kerner, Kristi
name: Tepper, Marek
name: Tänavots, Alo
name: Kaart, Tanel
name: Jõudu, Ivi
Publisher: name: Agronomy Research
Year: 2019
Subjects: beef cattle
semimembranosus
adductor femoris
longissimus
muscle
colour
shear force
cooking loss
Aberdeen Angus
article

description: The objective of the trial was to study the qualitative parameters of two muscles of Aberdeen Angus bulls with 250–300 kg carcass weight. After slaughter, longissimus thoracis et lumborum (LD) muscle and unseparated semimembranosus and adductor femoris(SMA) muscles were removed from the chilled carcasses. Muscles were vacuum-packed and wet aged at +2 °C for 10, 14, 18 and 20 days. Meat pH, electrical conductivity, shear force and colour were measured in all ageing times. Two thermal treatment methods (sous-vide (SV) and grilling) were used to determine cooking losses. The effects of muscles, ageing times and muscles by ageing times interaction was found with two-factorial analysis of variance. The effects of muscles, ageing times and muscle groups by ageing time interaction for raw and SV treated meat shear force was significant. Ageing decreased SV treated meat shear force from day 10 (40.8 N) to 18 (29.7 N). Fresh and SV treated LD muscle was tougher compared to the SMA muscle group, but SM showed a better response to the tenderness within 20 days of ageing. Redness and yellowness value was higher in the SM group in comparison to LD. Muscles showed good colour (lightness, redness and yellowness) stability within ageing for 20 days. No interactions were found between muscle groups and ageing times for SV treated and grilled beef cooking losses. However, SV treated meat lost more weight than grilled meat slices. The present study suggests that the optimal ageing time for meat is 18 days when the grilled meat cooking loss is the lowest.
Effect of ultrasonic treatment on the dissolution of milk solids during the reconstitutionof skim milk powder
Creators: name: Popova, N.
name: Potoroko, I.
name: Kretova, Y.
name: Ruskina, A.
name: Tsirulnichenko, L.
name: Kalinina, I.
Publisher: name: Agronomy Research
Year: 2019
Subjects: reconstituted milk products
ultrasonic exposure
skim milk powder
article

description: The producing reconstituted milk products that retain the same sensory properties as those of raw milk products is of high interest to the food industry In the technology of producing reconstituted milk processing products, the most significant factor that determines the component transition degree and the usefulness of the product being produced is the recombination process. It determines the possibility of bringing the organoleptic characteristics of reconstituted milk to the properties of the genuine one. One promising method to improve the process of milk powder recombination is ultrasonic exposure. The aim of the present study is to improve the process of milk powder recombination using ultrasonic exposure. The results of the conducted studies show that the ultrasonic treatment eliminates the agglomerates of dried milk particles in water and provides more accessible interaction between the particles and water, and as a result, improves the recombination process. The application of ultrasonic treatment during the reconstitution of the skim milk powder improved the dissolution of milk solids, as evidenced by around a 75% reduction in the amount of centrifuged insoluble sediment. The mass fractions of protein and lactose have increased by 4.8 and 6.5%, respectively.
Quantum Algorithms for Sampling Log-Concave Distributions and Estimating Normalizing Constants
Creators: name: Childs, Andrew M.
name: Li, Tongyang
name: Liu, Jin-Peng
name: Wang, Chunhao
name: Zhang, Ruizhe
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Machine Learning (cs.LG)
subject: Optimization and Control (math.OC)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Given a convex function $f\colon\mathbb{R}^{d}\to\mathbb{R}$, the problem of sampling from a distribution $\propto e^{-f(x)}$ is called log-concave sampling. This task has wide applications in machine learning, physics, statistics, etc. In this work, we develop quantum algorithms for sampling log-concave distributions and for estimating their normalizing constants $\int_{\mathbb{R}^d}e^{-f(x)}\mathrm{d} x$. First, we use underdamped Langevin diffusion to develop quantum algorithms that match the query complexity (in terms of the condition number $κ$ and dimension $d$) of analogous classical algorithms that use gradient (first-order) queries, even though the quantum algorithms use only evaluation (zeroth-order) queries. For estimating normalizing constants, these algorithms also achieve quadratic speedup in the multiplicative error $ε$. Second, we develop quantum Metropolis-adjusted Langevin algorithms with query complexity $\widetilde{O}(κ^{1/2}d)$ and $\widetilde{O}(κ^{1/2}d^{3/2}/ε)$ for log-concave sampling and normalizing constant estimation, respectively, achieving polynomial speedups in $κ,d,ε$ over the best known classical algorithms by exploiting quantum analogs of the Monte Carlo method and quantum walks. We also prove a $1/ε^{1-o(1)}$ quantum lower bound for estimating normalizing constants, implying near-optimality of our quantum algorithms in $ε$.
description: To appear in the proceedings of NeurIPS 2022
High Galactic latitude Fermi sources of gamma-rays with energies above 100 GeV
Creators: name: Neronov, A.
name: Semikoz, D. V.
name: Vovk, Ie.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present a catalog of sources of very high energy (E>100 GeV) gamma-rays detected by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope at Galactic latitudes |b|>=10 degrees. We cross-correlate the directions of individual photons with energies above 100 GeV detected by Fermi/LAT with the first year Fermi catalog of sources detected at lower energies. We find a significant correlation between the arrival directions of the highest energy photons and positions of Fermi sources, with the possibility of chance coincidences at the level of 1e-45. We present a list of Fermi sources contributing to the correlation signal. A similar analysis is performed to cross-correlate the catalog of BL Lac objects with the highest energy photons detected by Fermi. We produce a catalog of high Galactic latitude Fermi sources visible at 100-300 GeV energies. The catalog is divided into two parts. The first part contains a list of 50 higher significance sources among which there can be three possible false detections. The second part of the catalog contains a list of 25 lower significance sources, among which six are possibly false detections. Finally we identify eight additional sources from the cross-correlation analysis with the BL Lac catalog. The reported sources of E>100 GeV gamma-rays span a broad range of redshifts, up to z~1. Most of the sources are BL Lac type objects. Only 17 out of 83 objects in our list were previously reported as VHE gamma-ray sources.
description: 11 pages, 19 figures
Do Recall Elections Undermine Political Support? Insights from the Recall of the Mayor of Frankfurt in 2022
Creators: name: Springer, Frederik
name: Klein, Markus
name: Kühling, Christoph
Publisher: name: London : Taylor and Francis
Year: 2024
Subjects: subject: Recall
subject: Mayor
subject: Political Support
subject: Satisfaction with Democracy
subject: Abwahlverfahren
subject: Bürgermeister
subject: Politische Unterstützung
subject: Demokratiezufriedenheit
subject: Dewey Decimal Classification::300 | Sozialwissenschaften, Soziologie, Anthropologie

description: Concerns about the impact of recall referendums on political support have not been empirically examined so far. For this purpose, we conducted a postelection survey of around 800 respondents in Frankfurt after the mayoral election in March 2023 which followed a successful recall in November 2022. First, there is overwhelming support for recall elections, with 87% of respondents in favour. Even supporters of the recalled candidate rarely dislike the instrument and see little need for electoral reform. Second, only a few respondents are concerned about the impact of recalls on political support, but when they are, it often leads them to disapprove of recalls. Third, political support by the recall electoral losers – as measured by satisfaction with democracy and turnout in the successor election – is at worst only slightly reduced. Taken together, these findings do not suggest that recalls damage people’s views of the political system.
Optimal protocols for quantum metrology with noisy measurements
Creators: name: Zhou, Sisi
name: Michalakis, Spyridon
name: Gefen, Tuvia
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Measurement noise is a major source of noise in quantum metrology. Here, we explore preprocessing protocols that apply quantum controls to the quantum sensor state prior to the final noisy measurement (but after the unknown parameter has been imparted), aiming to maximize the estimation precision. We define the quantum preprocessing-optimized Fisher information, which determines the ultimate precision limit for quantum sensors under measurement noise, and conduct a thorough investigation into optimal preprocessing protocols. First, we formulate the preprocessing optimization problem as a biconvex optimization using the error observable formalism, based on which we prove that unitary controls are optimal for pure states and derive analytical solutions of the optimal controls in several practically relevant cases. Then we prove that for classically mixed states (whose eigenvalues encode the unknown parameter) under commuting-operator measurements, coarse-graining controls are optimal, while unitary controls are suboptimal in certain cases. Finally, we demonstrate that in multi-probe systems where noisy measurements act independently on each probe, the noiseless precision limit can be asymptotically recovered using global controls for a wide range of quantum states and measurements. Applications to noisy Ramsey interferometry and thermometry are presented, as well as explicit circuit constructions of optimal controls.
description: 41 pages, 3 figures, published version
Algebraic damping in the one-dimensional Vlasov equation
Creators: name: Barré, Julien
name: Olivetti, Alain
name: Yamaguchi, Yoshiyuki Y.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate the asymptotic behavior of a perturbation around a spatially non homogeneous stable stationary state of a one-dimensional Vlasov equation. Under general hypotheses, after transient exponential Landau damping, a perturbation evolving according to the linearized Vlasov equation decays algebraically with the exponent -2 and a well defined frequency. The theoretical results are successfully tested against numerical $N$-body simulations, corresponding to the full Vlasov dynamics in the large $N$ limit, in the case of the Hamiltonian mean-field model. For this purpose, we use a weighted particles code, which allows us to reduce finite size fluctuations and to observe the asymptotic decay in the $N$-body simulations.
description: 26 pages, 8 figures; text slightly modified, references added, typos corrected
Diversity enables the jump towards cooperation for the Traveler's Dilemma
Creators: name: Ramirez, Maria Alejandra
name: Smerlak, Matteo
name: Traulsen, Arne
name: Jost, Jürgen
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Science and Game Theory (cs.GT)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: Social dilemmas are situations in which collective welfare is at odds with individual gain. One widely studied example, due to the conflict it poses between human behaviour and game theoretic reasoning, is the Traveler's Dilemma. The dilemma relies on the players' incentive to undercut their opponent at the expense of losing a collective high payoff. Such individual incentive leads players to a systematic mutual undercutting until the lowest possible payoff is reached, which is the game's unique Nash equilibrium. However, if players were satisfied with a high payoff -- that is not necessarily higher than their opponent's -- they would both be better off individually and collectively. Here, we explain how it is possible to converge to this cooperative high payoff equilibrium. Our analysis focuses on decomposing the dilemma into a local and a global game. We show that players need to escape the local maximisation and jump to the global game, in order to reach the cooperative equilibrium. Using a dynamic approach, based on evolutionary game theory and learning theory models, we find that diversity, understood as the presence of suboptimal strategies, is the general mechanism that enables the jump towards cooperation.
description: 10 pages, 4 figures