cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Computing the Rabinowitz Floer homology of tentacular hyperboloids
Creators: name: Fauck, Alexander
name: Merry, Will J.
name: Wiśniewska, Jagna
Publisher: name: arXiv
Year: 2020
Subjects: subject: Symplectic Geometry (math.SG)
subject: FOS: Mathematics

description: We compute the Rabinowitz Floer homology for a class of non-compact hyperboloids $Σ\simeq S^{n+k-1}\times\mathbb{R}^{n-k}$. Using an embedding of a compact sphere $Σ_0\simeq S^{2k-1}$ into the hypersurface $Σ$, we construct a chain map from the Floer complex of $Σ$ to the Floer complex of $Σ_0$. In contrast to the compact case, the Rabinowitz Floer homology groups of $Σ$ are both non-zero and not equal to its singular homology. As a consequence, we deduce that the Weinstein Conjecture holds for any strongly tentacular deformation of such a hyperboloid.
description: v2: Fixed eleven typos in the title
Constraining Primordial Magnetism
Creators: name: Shaw, J. Richard
name: Lewis, Antony
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Primordial magnetic fields could provide an explanation for the galactic magnetic fields observed today, in which case they may also leave interesting signals in the CMB and the small-scale matter power spectrum. We discuss how to approximately calculate the important non-linear magnetic effects within the guise of linear perturbation theory, and calculate the matter and CMB power spectra including the SZ contribution. We then use various cosmological datasets to constrain the form of the magnetic field power spectrum. Using solely large-scale CMB data (WMAP7, QUaD and ACBAR) we find a 95% CL on the variance of the magnetic field at 1 Mpc of B_λ< 6.4 nG. When we include SPT data to constrain the SZ effect, we find a revised limit of B_λ< 4.1 nG. The addition of SDSS Lyman-alpha data lowers this limit even further, roughly constraining the magnetic field to B_λ< 1.3 nG.
description: 12 pages, 9 figures
Molecular diversity of four-component synthesis of pyrazole-based pyrido[2,3-d]pyrimidine-diones in water: a green synthesis
Creators: name: Mommahed Heravi, Majid
name: Daraie, Mansoureh
Publisher: name: figshare
Year: 2022
Subjects: subject: 30302 Nanochemistry and Supramolecular Chemistry
subject: FOS: Chemical sciences
subject: 30701 Quantum Chemistry
subject: 39904 Organometallic Chemistry
subject: Organic Chemistry
subject: 30502 Natural Products Chemistry
subject: 30599 Organic Chemistry not elsewhere classified
subject: 30205 Non-metal Chemistry
subject: Nuclear Chemistry
subject: 30504 Organic Green Chemistry
subject: 30303 Optical Properties of Materials

description: A novel one pot, four component synthesis of pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidine-diones, involving, hydrazine hydrate, ethyl acetoacetate, 6-amino-1,3-dimethyl uracil and an appropriate aryl aldehyde in the presence of two green catalysts in water, is reported.
Construction of soliton solutions of the matrix modified Korteweg-de Vries equation
Creators: name: Carillo, Sandra
name: Schiebold, Cornelia
Publisher: name: arXiv
Year: 2020
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: An explicit solution formula for the matrix modified KdV equation is presented, which comprises the solutions given in Ref. 7 (S. Carillo, M. Lo Schiavo, and C. Schiebold. Matrix solitons solutions of the modified Korteweg-de Vries equation. In: Nonlinear Dynamics of Structures, Systems and Devices, edited by W. Lacarbonara, B. Balachandran, J. Ma, J. Tenreiro Machado, G. Stepan (Springer, Cham, 2020), pp. 75-83). In fact, the solutions in Ref.7 are part of a subclass studied in detail by the authors in a forthcoming publication. Here several solutions beyond this subclass are constructed and discussed with respect to qualitative properties.
description: 10 pages, 6 figures, Proceedings of the Second International Nonlinear Dynamics Conference (NODYCON 2021), W. Lacarbonara et al, Ed.s
Corrigendum to “Dual lattice representations for O( N ) and CP( N − 1) models with a chemical potential” [Phys. Lett. B 749 (2015) 495–501]
Creators: name: Bruckmann, Falk
name: Gattringer, Christof
name: Kloiber, Thomas
name: Sulejmanpasic, Tin
Publisher: name: Universität Regensburg
Year: 2015
Subjects: subject: 530 Physik

description: SCOAP3
Post-Ehrenfest many-body quantum interferences in ultracold atoms far out of equilibrium
Creators: name: Tomsovic, Steven
name: Schlagheck, Peter
name: Ullmo, Denis
name: Urbina, Juan Diego
name: Richter, Klaus
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: 530 Physik

description: Far out-of-equilibrium many-body quantum dynamics in isolated systems necessarily generates interferences beyond an Ehrenfest timescale, where quantum and classical expectation values diverge. Of great recent interest is the role these interferences play in the spreading of quantum information across the many degrees of freedom, i.e., scrambling. Ultracold atomic gases provide a promising setting to explore these phenomena. Theoretically speaking, the heavily-relied-upon truncated Wigner approximation leaves out these interferences. We develop a semiclassical theory which bridges classical and quantum concepts in many-body bosonic systems and properly incorporates such missing quantum effects. For mesoscopically populated Bose-Hubbard systems, it is shown that this theory captures post-Ehrenfest quantum interference phenomena very accurately, and contains relevant phase information to perform many-body spectroscopy with high precision.
Preventing rheumatoid arthritis : understanding factors that influence decisions to take preventative treatments for rheumatoid arthritis
Creators: name: Spooner, Luke
Publisher: name: University of British Columbia
Year: 2019

description: Introduction: Currently, there are ongoing clinical trials for preventative treatments that aim to prevent and minimize the progression to RA in high risk individuals. However, preferences that drive people’s decision making in the context of a preventative treatment are unknown. With these clinical trials reporting their results within the next 2 years, this thesis aims to understand preferences of those who are at high risk of RA around preventative treatment and guide how these preferences can be best implemented in preventative treatment programs. Objectives: 1) To identify important attributes for uptake of a preventative treatment program for those who are at high risk of RA, 2) To identify the value that is placed on these attributes through a discrete choice experiment (DCE), and 3) To predict the potential uptake of a preventative treatment options in those who are at high risk of RA Methods To determine the attributes that were important for the uptake of a preventative treatment program for those who are at high risk of RA, individuals with RA, first-degree relatives and rheumatologists were interviewed. These interviews were analyzed through a Framework Method. A DCE provided insight into whether those who are at high risk of RA would be willing to take preventative treatment. Results: The qualitative Framework analysis of patient, first-degree relative, and rheumatologist focus groups yielded five different attributes to be included in a DCE. Including the five treatment related attributes in the DCE demonstrated that first-degree relatives and RA patients preferred preventative treatments that had high risk reduction of RA, were orally administered, minor reversible side effects, moderate certainty in estimates, and were preferred by the health care provider. Predicted uptake of preventative treatments ranged from 51% to 92%, with oral methotrexate having the highest and infusion rituximab having the lowest. Conclusion: This thesis provides understanding around preferences, and subsequent trade-offs that an at risk individual might make when considering preventative treatment for RA. Through these trade-offs, the most important attributes of a preventative treatment program have been identified, and the likely uptake of potential preventative treatments have been estimated.
‘Crying for home: Who really cares?’ A critical analysis of care giving in the context of Victorian residential care
Creators: name: Chalkley, Paul
Publisher: name: Australian Catholic University
Year: 2018

description: Residential care provides for approximately 500 children and young people in Victoria each year, yet the dynamics of providing care within this system have received little scholarly attention, at least in part because it forms a much smaller part of the system than home-based care – in 2014 there were 5,900 children and young people in foster care and kinship care in Victoria. It has long been recognised that, despite being highly traumatised and vulnerable, young people placed in the care of the state are often exposed to further distress, instability and torment because of the nature of the out-of-home care system, and the available literature confirms that this is certainly true in residential care. Central to the care these young people receive, and their experience of being ‘in care’, are the agents through which the care is delivered: residential care workers. This thesis fills a gap in knowledge by examining the perspectives and practice of residential care workers, asking how they understand their ability to support good outcomes for children and young people within the restrictions of residential care settings which are far from perfect. This thesis presents the findings of a qualitative study of interviews with twelve residential care workers that was guided by the principles of grounded theory. Led by the themes which emerged from these interviews, this project examines the pillars of good practice as residential care workers themselves understand them – both those which they can directly articulate, and those which are part of their tacit knowledge. The findings point to three key areas. Using the framework of ‘care’ as provided by Tronto, the three areas that emerged were (i) caring about, (ii) taking care of and (iii) care giving. At the heart of these areas are the concepts of being rooted in genuine relationships, trauma informed practice and connection to the community. These findings point to guiding principles that residential care workers see as helping them to be effective in not only doing their job, but also in providing authentic and personal care to the young people.
The rise of stochasticity in physics
Creators: name: Weidenmüller, Hans A.
Publisher: name: arXiv
Year: 2025
Subjects: subject: History and Philosophy of Physics (physics.hist-ph)
subject: FOS: Physical sciences

description: In the last 175 years, the physical understanding of
 nature has seen a revolutionary change. Until about 1850, Newton's
 theory and the mechanical world view derived from it provided the
 dominant view of the physical world, later supplemented by Maxwell's
 theory of the electromagnetic field. That approach was entirely
 deterministic and free of probabilistic concepts. In contrast to
 that conceptual edifice, today many fields of physics are governed
 by probabilistic concepts. Statistical mechanics in its classical or
 quantum version and random-matrix theory are obvious
 examples. Quantum mechanics is an intrinsically statistical
 theory. Classical chaos and its quantum manifestations also require
 a stochastic approach. The paper describes how a combination of
 discoveries and conceptual problems undermined the mechanical world
 view, led to novel concepts, and shaped the modern understanding of
 physics.
Growth of Crop and Livestock Output in Selected Developing Nations, 1948 to 1965
Creators: name: Schaub, John R.
name: Krause, Stanley F.
name: Schaub, John R.
name: Krause, Stanley F.
Publisher: name: Unknown
Year: 1968
Subjects: Crop Production/Industries
Livestock Production/Industries
Productivity Analysis
Research and Development/Tech Change/Emerging Technologies

description: Report Introduction: The overall development of a nation's agriculture is contingent not only on increasing crop and livestock output but on increasing per capita output as well. This report measures crop output for 17 developing countries: Bolivia, Dominican Republic, Ecuador, Guatemala, Guyana, Honduras, Jamaica, Nicaragua, Paraguay, Peru, and Uruguay in Latin America; Malagasy Republic, Mauritius, Morocco, and Senegal in Africa; Syria in the Near East; and Ceylon in the Far East. Data are also presented on livestock output and total agricultural output for 12 countries analyzed in a 1965 study by the U.S. Department of Agriculture. The 12 study countries are Argentina, Brazil, Chile, and Colombia in Latin America; Greece and Turkey in the Near East; Spain and Poland in Europe; the United Arab Republic (Egypt) in North Africa; Japan and Taiwan in the Far East. The objectives of this report are (1) to present a compilation of basic index numbers of agricultural output; (2) to measure levels, changes, sources of change, and compositional changes in crop output; and (3) to provide basic data relating to changes in livestock production in selected countries. The results should prove helpful in future research involving agricultural output, both in the formulation and the testing of hypotheses.
The role of an alpha animal in changing environmental conditions
Creators: name: Wolter, Riccarda
name: Pantel, Norbert
name: Stefanski, Volker
name: Krueger, Konstanze
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: alpha male, horse, Equus ferus przewalskii, bachelor group, group structure
subject: 590 Tiere (Zoologie)

description: The maintenance and development of conservation areas by grazing of large herbivores, such as Przewalski’s horses is common practice. Several nature conservation areas house male bachelor groups. When males are needed for breeding they are removed from the groups, often without considering group compositions and individual social positions. However, alpha animals are needed for ensuring group stability and decision making in potentially dangerous situations in several species. To investigate the importance of the alpha male in a bachelor group, we observed the behaviour of five Przewalski’s horse males during the enlargement of their enclosure. We analyzed the group’s social structure and movement orders, as well as the animals’ connectedness, activity budgets, and whether they moved with preferred group members and how factors such as social rank influenced the horses’ behaviour. We also investigated the excretion of glucocorticoid metabolites (CM) via faeces of the horses while exploring a new area as a parameter of glucocorticoid production. Our results show that the alpha male is important for a bachelor group in changing environmental conditions. The alpha male had the highest level of connectedness within the group. When exploring the new environment, its position in the group changed from previously being the last to being the first. Furthermore the whole group behaviour changed when exploring the new area. The stallions showed reduced resting behavior, increased feeding and did not stay close to each other. We found that the excretion of glucocorticoid metabolites of most horses rose only marginally during the first days on the new area while only the alpha male showed a significant increased amount of glucocorticoid production during the first day of the enclosure enlargement.
Integrability of the evolution equations for heavy–light baryon distribution amplitudes
Creators: name: Braun, V. M.
name: Derkachov, S. E.
name: Manashov, A. N.
Publisher: name: Universität Regensburg
Year: 2014
Subjects: subject: 530 Physik

description: We consider evolution equations describing the scale dependence of the wave function of a baryon containing an infinitely heavy quark and a pair of light quarks at small transverse separations, which is the QCD analogue of the helium atom. The evolution equations depend on the relative helicity of the light quarks. For the aligned helicities, we find that the equation is completely integrable, that is, it has a nontrivial integral of motion, and obtain exact analytic expressions for the eigenfunctions and the anomalous dimensions. The evolution equation for anti-aligned helicities contains an extra term that breaks integrability and creates a “bound state” with the anomalous dimension separated from the rest of the spectrum by a finite gap. The corresponding eigenfunction is found using numerical methods. It describes the momentum fraction distribution of the light quarks in, e.g., Λb-baryon at large scales.
description: SCOAP3
The Many Faces of Part-List Cuing—Evidence for the Interplay Between Detrimental and Beneficial Mechanisms
Creators: name: Lehmer, Eva-Maria
name: Bäuml, Karl-Heinz T.
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: episodic memory, retrieval cues, forgetting, context reactivation, collaborative inhibition
subject: 150 Psychologie

description: If participants study a list of items and, at test, receive a random selection of the studied items as retrieval cues, then such cuing often impairs recall of the remaining items. This effect, referred to as part-list cuing impairment, is a well-established finding in memory research that, over the years, has been attributed to quite different cognitive mechanisms. Here, we provide a review of more recent developments in research on part-list cuing. These developments (i) suggest a new view on part-list cuing impairment and a critical role of encoding for the effect, (ii) identify conditions in which part-list cuing impairment can turn into part-list cuing facilitation, and (iii) relate research on part-list cuing to a phenomenon from social memory, known as collaborative inhibition. The recent developments also include a new multi-mechanisms account, which attributes the effects of cuing to the interplay between detrimental mechanisms—like blocking, inhibition, or strategy disruption—and beneficial mechanisms—like context reactivation. The account provides a useful theoretical framework to describe both older and newer findings. It may guide future work on part-list cuing and may also motivate new research on collaborative inhibition.
Gromov K-area and jumping curves in CP^n
Creators: name: Savelyev, Yasha
Publisher: name: arXiv
Year: 2010
Subjects: subject: Symplectic Geometry (math.SG)
subject: Algebraic Geometry (math.AG)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: We give here some extensions of Gromov's and Polterovich's theorems on $\karea$ of $ \mathbb{CP} ^{n}$, particularly in the symplectic and Hamiltonian context. Our main methods involve Gromov-Witten theory, and some connections with Bott periodicity, and loop groups. The argument is closely connected with study of jumping curves in $ \mathbb{CP} ^{n}$, and as an upshot we prove a new symplectic geometric theorem on these jumping curves.
description: Version accepted by Alg. and Geom. Top
Linearly scaling direct method for accurately inverting sparse banded matrices
Creators: name: García-Risueño, Pablo
name: Echenique, Pablo
Publisher: name: arXiv
Year: 2010
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Numerical Analysis (math.NA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In many problems in Computational Physics and Chemistry, one finds a special kind of sparse matrices, termed "banded matrices". These matrices, which are defined as having non-zero entries only within a given distance from the main diagonal, need often to be inverted in order to solve the associated linear system of equations. In this work, we introduce a new O(n) algorithm for solving such a system, being n X n the size of the matrix. We produce the analytical recursive expressions that allow to directly obtain the solution, as well as the pseudocode for its computer implementation. Moreover, we review the different options for possibly parallelizing the method, we describe the extension to deal with matrices that are banded plus a small number of non-zero entries outside the band, and we use the same ideas to produce a method for obtaining the full inverse matrix. Finally, we show that the New Algorithm is competitive, both in accuracy and in numerical efficiency, when compared to a standard method based in Gaussian elimination. We do this using sets of large random banded matrices, as well as the ones that appear when one tries to solve the 1D Poisson equation by finite differences.
description: 24 pages, 5 figures, submitted to J. Comp. Phys
Parton distribution functions from reduced Ioffe-time distributions
Creators: name: Zhang, Jian-Hui
name: Chen, Jiunn-Wei
name: Monahan, Christopher
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: 530 Physik

description: We show that the correct way to extract parton distribution functions from the reduced Ioffe-time distribution, a ratio of the Ioffe-time distribution for a moving hadron and a hadron at rest, is through a factorization formula. This factorization exists because, at small distances, forming the ratio does not change the infrared behavior of the numerator, which is factorizable. We illustrate the effect of such a factorization by applying it to results in the literature.
description: SCOAP3
Fracturing ranked surfaces
Creators: name: Schrenk, K. J.
name: Araujo, N. A. M.
name: Andrade, J. S.
name: Herrmann, H. J.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Discretized landscapes can be mapped onto ranked surfaces, where every element (site or bond) has a unique rank associated with its corresponding relative height. By sequentially allocating these elements according to their ranks and systematically preventing the occupation of bridges, namely elements that, if occupied, would provide global connectivity, we disclose that bridges hide a new tricritical point at an occupation fraction $p=p_{c}$, where $p_{c}$ is the percolation threshold of random percolation. For any value of $p$ in the interval $p_{c}< p \leq 1$, our results show that the set of bridges has a fractal dimension $d_{BB} \approx 1.22$ in two dimensions. In the limit $p \rightarrow 1$, a self-similar fracture is revealed as a singly connected line that divides the system in two domains. We then unveil how several seemingly unrelated physical models tumble into the same universality class and also present results for higher dimensions.
Trade-offs in Decentralized Multi-Antenna Architectures: The WAX Decomposition
Creators: name: Alegría, Juan Vidal
name: Rusek, Fredrik
name: Edfors, Ove
Publisher: name: arXiv
Year: 2020
Subjects: subject: Signal Processing (eess.SP)
subject: Information Theory (cs.IT)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Current research on multi-antenna architectures is trending towards increasing the amount of antennas in the base stations (BSs) so as to increase the spectral efficiency. As a result, the interconnection bandwidth and computational complexity required to process the data using centralized architectures is becoming prohibitively high. Decentralized architectures can reduce these requirements by pre-processing the data before it arrives at a central processing unit (CPU). However, performing decentralized processing introduces also cost in complexity/interconnection bandwidth at the antenna end which is in general being ignored. This paper aims at studying the interplay between level of decentralization and the associated complexity/interconnection bandwidth requirement at the antenna end. To do so, we propose a general framework for centralized/decentralized architectures that can explore said interplay by adjusting some system parameters, namely the number of connections to the CPU (level of decentralization), and the number of multiplications/outputs per antenna (complexity/interconnection bandwidth). We define a novel matrix decomposition, the WAX decomposition, that allows information-lossless processing within our proposed framework, and we use it to obtain the operational limits of the interplay under study. We also look into some of the limitations of the WAX decomposition.
description: 14 pages, 9 figures, submitted to IEEE Transactions on Signal Processing. arXiv admin note: text overlap with arXiv:2003.01961
Square-Root Lasso: Pivotal Recovery of Sparse Signals via Conic Programming
Creators: name: Belloni, Alexandre
name: Chernozhukov, Victor
name: Wang, Lie
Publisher: name: arXiv
Year: 2010
Subjects: subject: Methodology (stat.ME)
subject: Statistics Theory (math.ST)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: We propose a pivotal method for estimating high-dimensional sparse linear regression models, where the overall number of regressors $p$ is large, possibly much larger than $n$, but only $s$ regressors are significant. The method is a modification of the lasso, called the square-root lasso. The method is pivotal in that it neither relies on the knowledge of the standard deviation $σ$ or nor does it need to pre-estimate $σ$. Moreover, the method does not rely on normality or sub-Gaussianity of noise. It achieves near-oracle performance, attaining the convergence rate $σ\{(s/n)\log p\}^{1/2}$ in the prediction norm, and thus matching the performance of the lasso with known $σ$. These performance results are valid for both Gaussian and non-Gaussian errors, under some mild moment restrictions. We formulate the square-root lasso as a solution to a convex conic programming problem, which allows us to implement the estimator using efficient algorithmic methods, such as interior-point and first-order methods.
Introducing DINGfest: An architecture for next generation SIEM systems
Creators: name: Menges, Florian
name: Böhm, Fabian
name: Vielberth, Manfred
name: Puchta, Alexander
name: Taubmann, Benjamin
name: Rakotondravony, Noëlle
name: Latzo, Tobias
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: Forensics, Virtual Machine Introspection, Visual Analytics, Security Information and Event Management, Identity and Access Management
subject: 004 Informatik

description: Isolated and easily protectable IT systems have developed into fragile and complex structures over the past years. These systems host manifold, flexible and highly connected applications, mainly in virtual environments. To ensure protection of those infrastructures, Security Incident and Event Management (SIEM) systems have been deployed. Such systems, however, suffer from many shortcomings such as lack of mechanisms for forensic readiness. In this extended abstract, we identify these shortcomings and propose an architecture which addresses them. It is developed within the DINGfest project, on which we report and for which we seek initial feedback from the community.
Non rectification of heat in graded Si-Ge alloys
Creators: name: Carillo, Sandra
name: Naso, Maria Grazia
name: Vuk, Elena
name: Zullo, Federico
Publisher: name: arXiv
Year: 2020
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We investigate the possibility to obtain a thermal diode with functionally graded Si-Ge alloys. A wire with variable section is considered. After the introduction of a formula giving the thermal conductivity of the wire as a function of the species content and of the diameter of the wire, numerical and analytical results are presented supporting the impracticability to get a thermal diode with the characteristics here considered. However, the present study opens the way to further generalisations amenable to give applicative promising results.
description: 9 pages, 3 figures, conference paper
Approximate oblique dual frames
Creators: name: Díaz, Jorge P.
name: Heineken, Sigrid B.
name: Morillas, Patricia M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Functional Analysis (math.FA)
subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: Primary 42C15, Secondary 42C40, 46C05, 41A30

description: In representations using frames, oblique duality appears in situations where the analysis and the synthesis has to be done in different subspaces. In some cases, we cannot obtain an explicit expression for the oblique duals and in others there exists only one oblique dual frame which has not the properties we need. Also, in practice the computations are not exact. To give a solution to these problems, in this work we introduce and investigate the notion of approximate oblique dual frames first in the setting of separable Hilbert spaces. We present several properties and provide different characterizations of approximate oblique dual frames. We focus then on approximate oblique dual frames in shift-invariant subspaces of L^2(R)and g ive different conditions on the generators that assure their existence. The importance of approximate oblique dual frames from a numerical and computational point of view is illustrated with an example of frame sequences generated by B-splines, where the previous results are used to construct approximate oblique dual frames which have better attributes than the exact ones. We provide an expression for the approximation error and study its behaviour.
Cognitive Loads in a Distance Training for Trainee Teachers
Creators: name: Stiller, Klaus D.
name: Bachmaier, Regine
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: Distance training, self-regulated learning, teacher training, higher education, computer anxiety, Computer attitude, intrinsic motivation, Cognitive Load Theory
subject: 150 Psychologie

description: How to effectively support students’ successful learning outcomes is one of the persistent problems of online and distance learning. One promising approach to this issue is to investigate the extent that learning is determined by learner characteristics and skills. This study explores the effects of domain-specific prior knowledge, intrinsic motivation, computer attitude, computer anxiety and learning management skills on learning in a distance-training course about media pedagogy for teachers. The data were collected from 127 trainee teachers who responded to various questionnaires and completed knowledge tests. We investigated whether the selected characteristics of learners could be used to model five cognitive load assessments that included ratings of content difficulty, learning ease, experienced pressure/tension, effort/importance while learning, and performing on tests. Computer anxiety and computer attitude were significant predictors of content difficulty, learning ease, and experienced pressure/tension. In addition, learning strategy usage reduced ratings of content difficulty. Effort/importance ratings were best modelled by intrinsic motivation and learning strategy usage. Performance was best predicted by prior knowledge, intrinsic motivation, and computer attitude.
Bäcklund transformations: a tool to study Abelian and non-Abelian nonlinear evolution equations
Creators: name: Carillo, Sandra
name: Schiebold, Cornelia
Publisher: name: arXiv
Year: 2021
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 58G37, 35Q53, 58F07

description: The KdV eigenfunction equation is considered: some explicit solutions are constructed. These, to the best of the authors' knowledge, new solutions represent an example of the powerfulness of the method devised. Specifically, Bäcklund transformation are applied to reveal algebraic properties enjoyed by nonlinear evolution equations they connect. Indeed, Bäcklund transformations, well known to represent a key tool in the study of nonlinear evolution equations, are shown to allow the construction of a net of nonlinear links, termed "Bäcklund chart", connecting Abelian as well as non Abelian equations. The present study concerns third order nonlinear evolution equations which are all connected to the KdV equation. In particular, the Abelian wide Bäcklund chart connecting these nonlinear evolution equations is recalled. Then, the links, originally established in the case of Abelian equations, are shown to conserve their validity when non Abelian counterparts are considered. In addition, the non-commutative case reveals a richer structure related to the multiplicity of non-Abelian equations which correspond to the same Abelian one. Reduction from the nc to the commutative case allow to show the connection of the KdV equation with KdV eigenfunction equation, in the "scalar" case. Finally, recently obtained matrix solutions of the mKdV equations are recalled.
description: 14 pages, 6 figures, conference FASNET 2020 (online)
Spectrum from the warped compactifications with the de Sitter universe
Creators: name: Minamitsuji, Masato
name: Uzawa, Kunihito
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We discuss the spectrum of the tensor metric perturbations and the stability of warped compactifications with the de Sitter spacetime in the higher-dimensional gravity. The spacetime structure is given in terms of the warped product of the non-compact direction, the spherical internal dimensions and the four-dimensional de Sitter spacetime. To realize a finite bulk volume, we construct the brane world model, using the cut-copy-paste method. Then, we compactify the spherical directions on the brane. In any case, we show the existence of the massless zero mode and the mass gap of it with massive Kaluza-Klein modes. Although the brane involves the spherical dimensions, no light massive mode is excited. We also investigate the scalar perturbations, and show that the model is unstable due to the existence of a tachyonic bound state, which seems to have the universal negative mass square, irrespective of the number of spacetime dimensions.
description: Journal version (JHEP)
title: "Statua di fanciullo con anatra", arte romana, inv. CVI (ITA/EN)
title: Scheda catalogo digitale Borghese
titleType: AlternativeTitle
Creators: name: Ciccarello, Giulia
name: Galleria Borghese
Publisher: name: Galleria Borghese
Year: 2024

description: Pubblicazione delle schede delle opere conservate nel museo ed estratte dal catalogo digitale di

Galleria Borghese, nelle due versioni esistenti online, in italiano e inglese.

Collegamento al catalogo digitale:

ITA: https://www.collezionegalleriaborghese.it/

EN: https://www.collezionegalleriaborghese.it/en
Towards a quantum time mirror for non-relativistic wave packets
Creators: name: Reck, Phillipp
name: Gorini, Cosimo
name: Goussev, Arseni
name: Krueckl, Viktor
name: Fink, Mathias
name: Richter, Klaus
Publisher: name: Universität Regensburg
Year: 2018
Subjects: subject: matter waves, quantum wave packets, quantum time mirrors, quantum scattering, nonlinear Schrödinger equation
subject: 530 Physik

description: We propose a method—a quantum time mirror (QTM)—for simulating a partial time-reversal of the free-space motion of a non-relativistic quantum wave packet. The method is based on a short-time spatially homogeneous perturbation to the wave packet dynamics, achieved by adding a nonlinear time-dependent term to the underlying Schrödinger equation. Numerical calculations, supporting our analytical considerations, demonstrate the effectiveness of the proposed QTM for generating a time-reversed echo image of initially localized matter-wave packets in one and two spatial dimensions. We also discuss possible experimental realizations of the proposed QTM.
description: This article supersedes the second half of arXiv:1603.07503v1, which we decided to split into two separate papers; one being arXiv1603.07503v2 the other one being the one at hand (arXiv:1801.01818).
The Impact of New Grain Varieties in Asia
Creators: name: Willett, Joseph W.
name: Willett, Joseph W.
Publisher: name: Unknown
Year: 1969
Subjects: Agricultural and Food Policy
Crop Production/Industries
Productivity Analysis
Research and Development/Tech Change/Emerging Technologies

description: Excerpts from the report Preface: This report on the impact of new varieties of grain in Asia was prepared by the Economic Research Service under an agreement with the Agency for International Development. It is part of a larger study on the outlook for demand of agricultural products produced by the less developed countries. This report estimates the contribution of the new varieties of rice and wheat to the production of grain in Asia in 1968-69. Since the estimate is necessarily rough, it is presented as a broad range of possibilities. The paper includes a discussion of various factors which may tend to slow the spread of the new varieties in Asia and also comments on some of the probable economic and social effects associated with these new varieties
Determining the Proximity Effect Induced Magnetic Moment in Graphene by Polarized Neutron Reflectivity and X-ray Magnetic Circular Dichroism
Creators: name: Aboljadayel, R. O. M.
name: Kinane, C. J.
name: Vaz, C. A. F.
name: Love, D. M.
name: Weatherup, R. S.
name: Braeuninger-Weimer, P.
name: Martin, M. -B.
name: Ionescu, A.
name: Caruana, A. J.
name: Charlton, T. R.
name: Llandro, J.
name: Monteiro, P. M. S.
name: Barnes, C. H. W.
name: Hofmann, S.
name: Langridge, S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We report the magnitude of the induced magnetic moment in CVD-grown epitaxial and rotated-domain graphene in proximity with a ferromagnetic Ni film, using polarized neutron reflectivity (PNR) and X-ray magnetic circular dichroism (XMCD). The XMCD spectra at the C K-edge confirms the presence of a magnetic signal in the graphene layer and the sum rules give a magnetic moment of up to $\sim\,0.47\,μ$_B/C atom induced in the graphene layer. For a more precise estimation, we conducted PNR measurements. The PNR results indicate an induced magnetic moment of $\sim$ 0.53 $μ$_B/C atom at 10 K for rotated graphene and $\sim$ 0.38 $μ$_B/C atom at 10 K for epitaxial graphene. Additional PNR measurements on graphene grown on a non-magnetic Ni_9Mo_1 substrate, where no magnetic moment in graphene is measured, suggest that the origin of the induced magnetic moment is due to the opening of the graphene's Dirac cone as a result of the strong C pz-3d hybridization.
description: 21 pages, 7 figures
Consistency of certain constitutive relations with quantum electromagnetism
Creators: name: Horsley, S. A. R.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Recent work by Philbin [1] has provided a Lagrangian theory that establishes a general method for the canonical quantization of the electromagnetic field in any dispersive, lossy, linear dielectric. Working from this theory, we extend the Lagrangian description to reciprocal and non- reciprocal magnetoelectric (bi-anisotropic) media, showing that some versions of the constitutive relations are inconsistent with a real Lagrangian, and hence with quantization. This amounts to a restriction on the magnitude of the magnetoelectric coupling. Moreover from the point of view of quantization, moving media are shown to be fundamentally different from stationary magnetoelectrics, despite the formal similarity in the constitutive relations.
description: 11 pages
Templates for Convex Cone Problems with Applications to Sparse Signal Recovery
Creators: name: Becker, Stephen R.
name: Candès, Emmanuel J.
name: Grant, Michael
Publisher: name: arXiv
Year: 2010
Subjects: subject: Optimization and Control (math.OC)
subject: Numerical Analysis (math.NA)
subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 90C05, 90C06, 90C25, 62J077

description: This paper develops a general framework for solving a variety of convex cone problems that frequently arise in signal processing, machine learning, statistics, and other fields. The approach works as follows: first, determine a conic formulation of the problem; second, determine its dual; third, apply smoothing; and fourth, solve using an optimal first-order method. A merit of this approach is its flexibility: for example, all compressed sensing problems can be solved via this approach. These include models with objective functionals such as the total-variation norm, ||Wx||_1 where W is arbitrary, or a combination thereof. In addition, the paper also introduces a number of technical contributions such as a novel continuation scheme, a novel approach for controlling the step size, and some new results showing that the smooth and unsmoothed problems are sometimes formally equivalent. Combined with our framework, these lead to novel, stable and computationally efficient algorithms. For instance, our general implementation is competitive with state-of-the-art methods for solving intensively studied problems such as the LASSO. Further, numerical experiments show that one can solve the Dantzig selector problem, for which no efficient large-scale solvers exist, in a few hundred iterations. Finally, the paper is accompanied with a software release. This software is not a single, monolithic solver; rather, it is a suite of programs and routines designed to serve as building blocks for constructing complete algorithms.
description: The TFOCS software is available at http://tfocs.stanford.edu This version has updated references
Structural, mineralogical and fluid evolution of the Shahumyan intermediate sulphidation vein deposit, Kapan district, Armenia
Creators: name: Yarra, Dharani Raja
Publisher: name: University of British Columbia
Year: 2018

description: The Kapan District located in the Syunik province of SE Armenia is part of the Lesser Caucasus. The district consists of multiple vein type deposits that were emplaced in the Middle-Upper Jurassic. The Shahumyan deposit is the only actively producing deposit within the district. Understanding vein geometry, and hydrothermal fluid evolution is fundamental in establishing the genesis and exploration significance within an epithermal vein district, providing both near mine and district scale targets. Over 120 veins of varying thicknesses (20cm to 3 m) are identified at the Shahumyan deposit. The veins are sub-vertical, south-dipping and trend east to northeast. Veins comprise of small bends, extensional jogs, soft and hard linked step-overs, pinch and swell structures and cymoid loops. These features are observed along both strike and down-dip of individual veins and contain higher metal grades relative to the rest of the vein. Along strike and down-dip connectivity of these structural features define high-grade ore-shoots within mineralized veins. Three main hydrothermal stages associated with mineralization are defined: Stage 1, pyrite, fine grained quartz ±chlorite; Stage 2a & b, pyrite, chalcopyrite, sphalerite, galena, sulfosalts, Au-Ag tellurides, fine and coarse white quartz, ±calcite; Stage 3; calcite, quartz, pyrite. Au-Ag-Pb tellurides are associated with localized brecciation. Tellurides are predominantly present in fractured sphalerite, pyrite, chalcopyrite and galena. Based on textures and fluid inclusion studies, Au-Ag-Pb tellurides are linked to boiling mechanisms. The epithermal event at The Shahumyan deposit is characterised by punctuated periods of hydrothermal brecciation interspersed with more quiescent periods when coarsely banded vein material was precipitated. Localized brecciation provide increased fluid permeability and ideal fluid pathways for mineralizing fluids. Localized brecciation corresponds with continued propagation or re-opening of the fracture-vein system. Localized boiling is interpreted to be the primarily driver for Au-Ag telluride precipitation.
H3PMo12O40 immobilized chitosan/Fe3O4 as a novel efficient, green and recyclable nanocatalyst in the synthesis of pyrano-pyrazole derivatives
Creators: name: Mommahed Heravi, Majid
name: Ayati, Ali
name: Daraie, Mansoureh
name: Tanhaei, Bahareh
name: Bamoharram, Fatemeh F.
name: Sillanpää, Mika
Publisher: name: figshare
Year: 2022
Subjects: subject: 30302 Nanochemistry and Supramolecular Chemistry
subject: FOS: Chemical sciences
subject: 30701 Quantum Chemistry
subject: 39904 Organometallic Chemistry
subject: Organic Chemistry
subject: 30502 Natural Products Chemistry
subject: 30205 Non-metal Chemistry
subject: Nuclear Chemistry
subject: 30504 Organic Green Chemistry
subject: 30303 Optical Properties of Materials
subject: 30599 Organic Chemistry not elsewhere classified

description: A novel nanomagnetic composite heteropolyacid immobilized chitosan/Fe3O4 was prepared via a facile one-pot synthetic approach. This magnetically recoverable nanocatalyst, H3PMo12O40/chitosan/Fe3O4 (PMo/chit/Fe3O4), was fully characterized by XRD, FTIR, SEM and EDX analysis methods. A rapid, efficient and the chemoselective synthesis of different pyrano-pyrazole derivatives was achieved in excellent yields via a one-pot four-component reaction in the presence of catalytic amount of PMo/Chit/Fe3O4.
High accuracy wide field imaging method in radio interferometry
Creators: name: Ye, Haoyang
name: Gull, Steve F.
name: Tan, Sze M.
name: Nikolic, Bojan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: With the development of modern radio interferometers, wide-field continuum surveys have been planned and undertaken, for which accurate wide-field imaging methods are essential. Based on the widely-used W-stacking method, we propose a new wide-field imaging algorithm that can synthesize visibility data from a model of the sky brightness via degridding, able to construct dirty maps from measured visibility data via gridding. Results carry the smallest approximation error yet achieved relative to the exact calculation involving the direct Fourier transform. In contrast to the original W-stacking method, the new algorithm performs least-misfit optimal gridding (and degridding) in all three directions, and is capable of achieving much higher accuracy than is feasible with the original algorithm. In particular, accuracy at the level of single precision arithmetic is readily achieved by choosing a least-misfit convolution function of width W=7 and an image cropping parameter of x0=0.25. If the accuracy required is only that attained by the original W-stacking method, the computational cost for both the gridding and FFT steps can be substantially reduced using the proposed method by making an appropriate choice of the width and image cropping parameters.
description: 12 pages, 11 figures