cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
What helps the development of new vaccine products : an economic analysis of R&D spending in the vaccine industry, the productivity of biotechnological research and related issues in science and technology policy
Creators: name: Kramer, Stefan
Publisher: name: University of Westminster
Year: 2002

description: This thesis was motivated by concern regarding an alleged lack of investment in research and development of vaccine products which could offer considerable net benefit to societies, particularly in the developing world. The aim of this thesis is to provide decision support for science and technology policy which aims to promote private research and development in new vaccine products. The literature suggests that markets fail to allocate sufficient resources to the development of new vaccines. Science policy can attempt to influence the direction of research through government subsidies, targeted fiscal support, regulatory measures or policies designed to influence human capital formation. In order to assess the effectiveness of these measures in the context of the vaccine industry a R&D resource allocation model is empirically tested in Chapter Six. In a partial adjustment specification and error correction form, a relationship between the cost of funds and the allocation of R&D resources could be established for the US vaccine industry over a twenty five year period. It was also found that public sector research effort does not appear to 'crowd out' private sector R&D spending. Other factors emphasised in the literature, such as the relative market size and improvements in patent protection, were not significantly related to research intensity. In the Second Part of this thesis the scope has been extended to include firms in the biotechnology industry which play an important role in vaccine innovation. The focus of research in Chapters Seven and Eight is on collaborative research which is believed to be a particularly productive way to bring new vaccines to the market. In an empirical investigation of established US biotech firms it was suggested that companies which undertake more science or co-operate more closely with universities than their competitors are likely to show a higher level of research productivity. What could not be established is whether scientific activity results in superior research outcomes or whether successful companies attract star scientists who are more likely to publish the results of their work. This emphasises the importance of the promotion of scientific talent and the movement of scientists between the public and private sectors and internationally. It is suggested in Chapter Nine that the institutional structure of higher education has an important effect on the mobility of scientists: a country which imports highly-skilled personnel may maintain or improve its technological capabilities by this means. Using data from the British Higher Education Statistics Agency (HESA) it is suggested that contrary to belief, disciplines such as biological sciences experience a moderate net inflow of scientists from the private sector and abroad.
Evolution of Weyl orbit and quantum Hall effect in Dirac semimetal Cd3As2
Creators: name: Zhang, Cheng
name: Narayan, Awadhesh
name: Lu, Shiheng
name: Zhang, Jinglei
name: Zhang, Huiqin
name: Ni, Zhuoliang
name: Yuan, Xiang
name: Liu, Yanwen
name: Park, Ju-Hyun
name: Zhang, Enze
name: Wang, Weiyi
name: Liu, Shanshan
name: Cheng, Long
name: Pi, Li
name: Sheng, Zhigao
name: Sanvito, Stefano
name: Xiu, Faxian
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Owing to the coupling between open Fermi arcs on opposite surfaces, topological Dirac semimetals exhibit a new type of cyclotron orbit in the surface states known as Weyl orbit. Here, by lowering the carrier density in Cd3As2 nanoplates, we observe a crossover from multiple- to single-frequency Shubnikov-de Haas (SdH) oscillations when subjected to out-of-plane magnetic field, indicating the dominant role of surface transport. With the increase of magnetic field, the SdH oscillations further develop into quantum Hall state with non-vanishing longitudinal resistance. By tracking the oscillation frequency and Hall plateau, we observe a Zeeman-related splitting and extract the Landau level index as well as sub-band number. Different from conventional two-dimensional systems, this unique quantum Hall effect may be related to the quantized version of Weyl orbits. Our results call for further investigations into the exotic quantum Hall states in the low-dimensional structure of topological semimetals.
description: Accepted by Nature Communications
Connection probabilities for conformal loop ensembles
Creators: name: Miller, Jason
name: Werner, Wendelin
Publisher: name: arXiv
Year: 2017
Subjects: subject: Probability (math.PR)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: The goal of the present paper is to explain, based on properties of the conformal loop ensembles CLE$_κ$ (both with simple and non-simple loops, i.e., for the whole range $κ\in (8/3, 8)$) how to derive the connection probabilities in conformal rectangles for a conditioned version of CLE$_κ$ which can be interpreted as a CLE$_κ$ with wired/free/wired/free boundary conditions on four boundary arcs (the wired parts being viewed as portions of to-be-completed loops). In particular, in the case of a conformal square, we prove that the probability that the two wired sides hook up so that they create one single loop is equal to $1/(1 - 2 \cos (4 π/ κ))$. Comparing this with the corresponding connection probabilities for discrete O(N) models for instance indicates that if a dilute O(N) model (respectively a critical FK(q)-percolation model on the square lattice) has a non-trivial conformally invariant scaling limit, then necessarily this scaling limit is CLE$_κ$ where $κ$ is the value in $(8/3, 4]$ such that $-2 \cos (4 π/ κ)$ is equal to $N$ (resp. the value in $[4,8)$ such that $-2 \cos (4π/ κ)$ is equal to $\sqrt {q}$). Our arguments and computations build on the one hand on Dubédat's SLE commutation relations (as developed and used by Dubédat, Zhan or Bauer-Bernard-Kytölä) and on the other hand, on the construction and properties of the conformal loop ensembles and their relation to Brownian loop-soups, restriction measures, and the Gaussian free field, as recently derived in works with Sheffield and with Qian.
description: 37 pages, to appear in Comm. in Math. Phys
Resilient Distributed Estimation Through Adversary Detection
Creators: name: Chen, Yuan
name: Kar, Soummya
name: Moura, José M. F.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: This paper studies resilient multi-agent distributed estimation of an unknown vector parameter when a subset of the agents is adversarial. We present and analyze a Flag Raising Distributed Estimator ($\mathcal{FRDE}$) that allows the agents under attack to perform accurate parameter estimation and detect the adversarial agents. The $\mathcal{FRDE}$ algorithm is a consensus+innovations estimator in which agents combine estimates of neighboring agents (consensus) with local sensing information (innovations). We establish that, under $\mathcal{FRDE}$, either the uncompromised agents' estimates are almost surely consistent or the uncompromised agents detect compromised agents if and only if the network of uncompromised agents is connected and globally observable. Numerical examples illustrate the performance of $\mathcal{FRDE}$.
MPEC 2023-F107 : 2020 RH147
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2020 RH147

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
The (1+$λ$) Evolutionary Algorithm with Self-Adjusting Mutation Rate
Creators: name: Doerr, Benjamin
name: Gießen, Christian
name: Witt, Carsten
name: Yang, Jing
Publisher: name: arXiv
Year: 2017
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Computer and information sciences

description: We propose a new way to self-adjust the mutation rate in population-based evolutionary algorithms in discrete search spaces. Roughly speaking, it consists of creating half the offspring with a mutation rate that is twice the current mutation rate and the other half with half the current rate. The mutation rate is then updated to the rate used in that subpopulation which contains the best offspring. We analyze how the $(1+λ)$ evolutionary algorithm with this self-adjusting mutation rate optimizes the OneMax test function. We prove that this dynamic version of the $(1+λ)$ EA finds the optimum in an expected optimization time (number of fitness evaluations) of $O(nλ/\logλ+n\log n)$. This time is asymptotically smaller than the optimization time of the classic $(1+λ)$ EA. Previous work shows that this performance is best-possible among all $λ$-parallel mutation-based unbiased black-box algorithms. This result shows that the new way of adjusting the mutation rate can find optimal dynamic parameter values on the fly. Since our adjustment mechanism is simpler than the ones previously used for adjusting the mutation rate and does not have parameters itself, we are optimistic that it will find other applications.
description: An extended abstract of this report appeared in the proceedings of the 2017 Genetic and Evolutionary Computation Conference (GECCO 2017), https://doi.org/10.1145/3071178.3071279. Version 2: several extensions, most notably regarding experimental results; Version 3: revised presentation and added more experiments
Revealing the stability and efficiency enhancement in mixed halide perovskites MAPb(I$_{1-x}$Cl$_x$)$_3$ with ab initio calculations
Creators: name: Jong, Un-Gi
name: Yu, Chol-Jun
name: Jang, Yong-Man
name: Ri, Gum-Chol
name: Hong, Song-Nam
name: Pae, Yong-Hyon
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A little addition of Cl to \ce{MAPbI3} has been reported to improve the material stability as well as light harvesting and carrier conducting properties of organometal trihalide perovskites, the key component of perovskite solar cell (PSC). However, the mechanism of performance enhancement of PSC by Cl addition is still unclear. Here, we apply the efficient virtual crystal approximation method to revealing the effects of Cl addition on the structural, electronic, optical properties and material stability of \ce{MAPb(I_{1-x}Cl_x)3}. Our {\it ab initio} calculations present that as the increase of Cl content cubic lattice constants and static dielectric constants decrease linearly, while band gaps and exciton binding energies increase quadratically. Moreover, we find the minimum of exciton binding energy at the Cl content of 7\%, at which the chemical decomposition reaction changes coincidentally to be from exothermic to endothermic. Interactions among constituents of compound and electronic charge transferring during formation are carefully discussed. This reveals new prospects for understanding and designing of stable, high efficiency PSCs.
Convexity of level sets and a two-point function
Creators: name: Weinkove, Ben
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We establish a maximum principle for a two-point function in order to analyze the convexity of level sets of harmonic functions. We show that this can be used to prove a strict convexity result involving the smallest principal curvature of the level sets.
description: 10 pages, v2 minor corrections, to appear in Pacific J. Math
Necessary conditions for linear convergence of iterated expansive, set-valued mappings with application to alternating projections
Creators: name: Luke, D. Russell
name: Teboulle, Marc
name: Thao, Nguyen H.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 49J53, 65K10

description: We present necessary conditions for monotonicity, in one form or another, of fixed point iterations of mappings that violate the usual nonexpansive property. We show that most reasonable notions of linear-type monotonicity of fixed point sequences imply {\em metric subregularity}. This is specialized to the alternating projections iteration where the metric subregularity property takes on a distinct geometric characterization of sets at points of intersection called {\em subtransversality}. Our more general results for fixed point iterations are specialized to establish the necessity of subtransversality for consistent feasibility with a number of reasonable types of sequential monotonicity, under varying degrees of assumptions on the regularity of the sets.
description: 22 pages, 35 references
Supplementary document for Dynamic dual-functional optical waveplate based on phase-change meta-molecules - 6433697.pdf
Creators: name: Cai, Ziru
name: Ding, Yingtao
name: Chen, Zhiming
name: Zheng, Zi-Wei
name: Ding, Fei
Publisher: name: Optica Publishing Group
Year: 2023
Subjects: Uncategorized

description: Supplement 1
On the Apparent Ambiguities in the Post-Newtonian Expansion for Binary Systems
Creators: name: Porto, Rafael A.
name: Rothstein, Ira Z.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discuss the source of the apparent ambiguities arising in the calculation of the dynamics of binary black holes within the Post-Newtonian framework. Divergences appear in both the near and far zone calculations, and may be of either ultraviolet (UV) or infrared (IR) nature. The effective field theory (EFT) formalism elucidates the origin of the singularities which may introduce apparent ambiguities. In particular, the only (physical) 'ambiguity parameters' that necessitate a matching calculation correspond to unknown finite size effects, which first appear at fifth Post-Newtonian (5PN) order for non-spinning bodies. We demonstrate that the ambiguities linked to IR divergences in the near zone, that plague the recent derivations of the binding energy at 4PN order, both in the ADM and 'Fokker-action' approach, can be resolved by implementing the so-called 'zero-bin' subtraction in the EFT framework. The procedure yields ambiguity-free results without the need of additional information beyond the PN expansion.
description: 12 pages. 1 figure. To appear in Phys. Rev. D
Subnanosecond Time-to-Digital Converter Implemented in a Kintex-7 FPGA
Creators: name: Sano, Yuta
name: Horii, Yasuyuki
name: Ikeno, Masahiro
name: Sasaki, Osamu
name: Tomoto, Makoto
name: Uchida, Tomohisa
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Time-to-digital converters (TDCs) are used in various fields, including high-energy physics. One advantage of implementing TDCs in field-programmable gate arrays (FPGAs) is the flexibility on the modification of the logics, which is useful to cope with the changes in the experimental conditions. Recent FPGAs make it possible to implement TDCs with a time resolution less than 10 ps. On the other hand, various drift chambers require a time resolution of O(0.1) ns, and a simple and easy-to-implement TDC is useful for a robust operation. Herein an eight-channel TDC with a variable bin size down to 0.28 ns is implemented in a Xilinx Kintex-7 FPGA and tested. The TDC is based on a multisampling scheme with quad phase clocks synchronised with an external reference clock. Calibration of the bin size is unnecessary if a stable reference clock is available, which is common in high-energy physics experiments. Depending on the channel, the standard deviation of the differential nonlinearity for a 0.28 ns bin size is 0.13-0.31. The performance has a negligible dependence on the temperature. The power consumption and the potential to extend the number of channels are also discussed.
description: 8 pages, 13 figures
Diffraction of electromagnetic waves in the gravitational field of the Sun
Creators: name: Turyshev, Slava G.
name: Toth, Viktor T.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We consider the propagation of electromagnetic (EM) waves in the gravitational field of the Sun within the first post-Newtonian approximation of the general theory of relativity. We solve Maxwell's equations for the EM field propagating on the background of a static mass monopole and find an exact closed form solution for the Debye potentials, which, in turn, yield a solution to the problem of diffraction of EM waves in the gravitational field of the Sun. The solution is given in terms of the confluent hypergeometric function and, as such, it is valid for all distances and angles. Using this solution, we develop a wave-theoretical description of the solar gravitational lens (SGL) and derive expressions for the EM field and energy flux in the immediate vicinity of the focal line of the SGL. Aiming at the potential practical applications of the SGL, we study its optical properties and discuss its suitability for direct high-resolution imaging of a distant exoplanet.
description: 43 pages, 9 figures, updated to match published version
Revisiting Clonostachys
Creators: name: Zhao, Lin
name: Groenewald, Johannes Z.
name: Crous, Pedro W.
Publisher: name: Zenodo
Year: 2022

description: Poster presented at the 52nd Congress of the Southern African Society for Plant Pathologists (SASSP), Future Africa campus, Pretoria, South Africa, 1-3 August 2022
On Consistency of Compressive Spectral Clustering
Creators: name: Pydi, Muni Sreenivas
name: Dukkipati, Ambedkar
Publisher: name: arXiv
Year: 2017
Subjects: subject: Machine Learning (stat.ML)
subject: Information Theory (cs.IT)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Spectral clustering is one of the most popular methods for community detection in graphs. A key step in spectral clustering algorithms is the eigen decomposition of the $n{\times}n$ graph Laplacian matrix to extract its $k$ leading eigenvectors, where $k$ is the desired number of clusters among $n$ objects. This is prohibitively complex to implement for very large datasets. However, it has recently been shown that it is possible to bypass the eigen decomposition by computing an approximate spectral embedding through graph filtering of random signals. In this paper, we analyze the working of spectral clustering performed via graph filtering on the stochastic block model. Specifically, we characterize the effects of sparsity, dimensionality and filter approximation error on the consistency of the algorithm in recovering planted clusters.
description: Accepted for publication at the 2018 IEEE International Symposium on Information Theory (ISIT), Vail, Colorado, USA
MPEC 2023-P69 : 2023 PZ
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 PZ

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Nucleon axial form factors using lattice QCD simulations with a physical value of the pion mass
Creators: name: Alexandrou, Constantia
name: Constantinou, Martha
name: Hadjiyiannakou, Kyriakos
name: Jansen, Karl
name: Kallidonis, Christos
name: Koutsou, Giannis
name: Aviles-Casco, Alejandro Vaquero
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We present results on the nucleon axial and induced pseudo-scalar form factors using an ensemble of two degenerate twisted mass clover-improved fermions generated at the physical value of the pion mass. We evaluate the isovector and the isoscalar, as well as, the strange and the charm axial form factors. The disconnected contributions are evaluated using recently developed methods that include deflation of the lower eigenstates, allowing us to extract the isoscalar, strange and charm axial form factors. We find that the disconnected quark loop contributions are non-zero and particularly large for the induced pseudo-scalar form factor.
description: Replaced with the published version
Pain and social context: social, contextual and environmental factors in the perception of acute pain
Creators: name: Williams, David
Publisher: name: University of Westminster
Year: 2003

description: A number of factors have been identified as generally reliable predictors of individual differences in responses to acute pain (e. g. sex, personality traits and cultural affiliation). These factors constitute relatively stable, long-term characteristics of an individual. However, there is also significant within-individual variation in response to acute pain, suggesting that factors other than individual characteristics also influence pain response. It is known that affective-motivational state is a significant component of pain, and it has been argued also that the process of automatic evaluation effects changes in affectivemotivational state through the activity of limbic structures associated with the detection and processing of emotionally valenced environmental information. This thesis proposes that through this mechanism, qualities of the immediate environment can act as modifiers of pain response. A series of experiments were conducted to test for the effects of manipulation of social, contextual and environmental features on responses to a mechanical pain stimulus. The results show that manipulation of preparatory information and locus of perceived control within the experimental dyad resulted in significant changes in response to the second of two pain stimuli of identical intensity. Also, both the sex of the assessor and the presence of a negatively valenced feature in the test environment were shown to influence pain response significantly. These results are in line with evidence from research into automaticity and automatic evaluation, and recent evidence concerning the roles of limbic areas in emotional processing and pain. The results provide further insight into the nature of acute pain, and suggest that individual variation in pain response may be explained in terms of an integrated biopsychosocial model, which includes what is known of the neural bases underlying the sensory and affective-motivational components of pain (the pain matrix), but also acknowledges the roles of socially acquired, long-term cognitive structures relating to individual traits, and the influence of automatic evaluation. The results have significant implications for clinical and research practices as they indicate that qualities of the environment may impact upon clinical and experimental pain measurement. Moreover, they indicate that individuals can be 'primed' for pain by qualities of their environment and as a result, may suffer unnecessarily during acutely painful clinical procedures. However, awareness of these principles may be useful in developing methods of reducing suffering in those situations.
The Lamb shift and the gravitational binding energy for binary black holes
Creators: name: Porto, Rafael A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We show that the correction to the gravitational binding energy for binary black holes due to the tail effect resembles the Lamb shift in the Hydrogen atom. In both cases a 'conservative' effect arises from interactions with 'radiation' modes, and moreover an explicit cancelation between near and far zone divergences is at work. In addition, regularization scheme-dependence may introduce ambiguity parameters. This is remediated, within an effective field theory approach, by the implementation of the zero-bin subtraction. We illustrate the procedure explicitly for the Lamb shift, by performing an ambiguity-free derivation within the framework of non-relativistic electrodynamics. We also derive the renormalization group equations from which we reproduce Bethe logarithm (at order $α_e^5 \log α_e$), and likewise the contribution to the gravitational potential from the tail effect (proportional to $v^8 \log v$).
description: 18 pages. 6 figures. To appear in Phys. Rev. D
Relationships Between Characteristics of the Line-of-Sight Magnetic Field and Solar Flare Forecasts
Creators: name: Sadykov, Viacheslav M
name: Kosovichev, Alexander G
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We analyze the relationship between the flare X-ray peak flux, and characteristics of the Polarity Inversion Line (PIL) and Active Regions (AR), derived from line-of-sight (LOS) magnetograms. The PIL detection algorithm based on a magnetogram segmentation procedure is applied for each AR with 1 hour cadence. The PIL and AR characteristics are associated with the AR flare history and divided into flaring and non-flaring cases. Effectiveness of the derived characteristics for flare forecasting is determined by the number of non-flaring cases separated from flaring cases by a certain threshold, and by their Fisher ranking score. The Support Vector Machine (SVM) classifier trained only on the PIL characteristics is used for the flare prediction. We have obtained the following results: (1) the PIL characteristics are more effective than global characteristics of ARs, (2) the highest True Skill Statistics (TSS) values of 0.76$\pm$0.03 for $\geq$M1.0 flares and 0.84$\pm$0.07 for $\geq$X1.0 flares are obtained using the "Sigmoid" SVM kernel, (3) the TSS scores obtained using only the LOS magnetograms are slightly lower than the scores obtained using vector magnetograms, but significantly better than current expert-based predictions, (4) for prediction of $\geq$M1.0 class flares 74.4 % of all cases, and 91.2 % for $\geq$X1.0 class, can be pre-classified as negative with no significant effect on the results, (5) the inclusion of global AR characteristics does not improve the forecast. The study confirms the unique role of the PIL region characteristics in the flare initiation process, and demonstrate possibilities of flare forecasting using only the line-of-sight magnetograms.
description: 25 pages, 2 figures, 4 tables
Well-posedness of the Two-dimensional Nonlinear Schrödinger Equation with Concentrated Nonlinearity
Creators: name: Carlone, Raffaele
name: Correggi, Michele
name: Tentarelli, Lorenzo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mathematical Physics (math-ph)
subject: Analysis of PDEs (math.AP)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We consider a two-dimensional nonlinear Schrödinger equation with concentrated nonlinearity. In both the focusing and defocusing case we prove local well-posedness, i.e., existence and uniqueness of the solution for short times, as well as energy and mass conservation. In addition, we prove that this implies global existence in the defocusing case, irrespective of the power of the nonlinearity, while in the focusing case blowing-up solutions may arise.
description: 39 pages, pdfLaTex. Final version to appear in Ann. I. H. Poincar\'e - AN
MPEC 2023-P70 : 2023 PA1
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 PA1

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Quantum noise reduction in intensity-sensitive surface plasmon resonance sensors
Creators: name: Lee, Joong-Sung
name: Huynh, Trung
name: Lee, Su-Yong
name: Lee, Kwang-Geol
name: Lee, Jinhyoung
name: Tame, Mark
name: Rockstuhl, Carsten
name: Lee, Changhyoup
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We investigate the use of twin-mode quantum states of light with symmetric statistical features in their photon number for improving intensity-sensitive surface plasmon resonance (SPR) sensors. For this purpose, one of the modes is sent into a prism setup where the Kretschmann configuration is employed as a sensing platform and the analyte to be measured influences the SPR excitation conditions. This influence modifies the output state of light that is subsequently analyzed by an intensity-difference measurement scheme. We show that quantum noise reduction is achieved not only as a result of the sub-Poissonian statistical nature of a single mode, but also as a result of the non-classical correlation of the photon number between the two modes. When combined with the high sensitivity of the SPR sensor, we show that the use of twin-mode quantum states of light notably enhances the estimation precision of the refractive index of an analyte. With this we are able to identify a clear strategy to further boost the performance of SPR sensors, which are already a mature technology in biochemical and medical sensing applications.
description: 8 pages, 3 figures
Negative (and Positive) Circles in Signed Graphs: A Problem Collection
Creators: name: Zaslavsky, Thomas
Publisher: name: arXiv
Year: 2017
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C22 (Primary), 05C20, 05C38, 05C50, 05C70, 05C75 (Secondary)

description: A signed graph is a graph whose edges are labelled positive or negative. The sign of a circle (cycle, circuit) is the product of the signs of its edges. Most of the essential properties of a signed graph depend on the signs of its circles. Here I describe several questions regarding negative circles and their cousins the positive circles. Topics include incidence between signed circles and edges or vertices, characterizing signed graphs with special circle properties, counting negative circles, signed-circle packing and covering, signed circles and eigenvalues, and directed cycles in signed digraphs. A few of the questions come with answers.
description: 21 pp (V1); 23 pp (V2), updated and slightly expanded
Spin-charge separation in an Aharonov-Bohm interferometer
Creators: name: Dmitriev, A. P.
name: Gornyi, I. V.
name: Kachorovskii, V. Yu.
name: Polyakov, D. G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study manifestations of spin-charge separation (SCS) in transport through a tunnel-coupled interacting single-channel quantum ring. We focus on the high-temperature case (temperature $T$ larger than the level spacing $Δ$) and discuss both the classical (flux-independent) and interference contributions to the tunneling conductance of the ring in the presence of magnetic flux. We demonstrate that the SCS effects, which arise solely from the electron-electron interaction, lead to the appearance of a peculiar fine structure of the electron spectrum in the ring. Specifically, each level splits into a series of sublevels, with their spacing governed by the interaction strength. In the high-$T$ limit, the envelope of the series contains of the order of $T/Δ$ sublevels. At the same time, SCS suppresses the tunneling width of the sublevels by a factor of $Δ/T$. As a consequence, the classical transmission through the ring remains unchanged compared to the noninteracting case: the suppression of tunneling is compensated by the increase of the number of tunneling channels. On the other hand, the flux-dependent contribution to the conductance depends on the interaction-induced dephasing rate which is known to be parametrically increased by SCS in an infinite system. We show, however, that SCS is not effective for dephasing in the limit of weak tunneling. Moreover, generically, in the almost closed ring, the dephasing rate does not depend on the interaction strength and is determined by the tunneling coupling to the leads. In certain special symmetric cases, dephasing is further suppressed. Similar to the spinless case, the high-$T$ conductance shows, as a function of magnetic flux, a sequence of interaction-induced sharp negative peaks on top of the classical contribution.
description: 23 pages, 9 figures (Fig. 2 and new references added, introduction extended)
MPEC 2023-P71 : 2023 PB1
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 PB1

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
The $H_0$ tension in light of vacuum dynamics in the Universe
Creators: name: Sola, Joan
name: Gomez-Valent, Adria
name: Perez, Javier de Cruz
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Despite the outstanding achievements of modern cosmology, the classical dispute on the precise value of $H_0$, which is the first ever parameter of modern cosmology and one of the prime parameters in the field, still goes on and on after over half a century of measurements. Recently the dispute came to the spotlight with renewed strength owing to the significant tension (at $>3σ$ c.l.) between the latest Planck determination obtained from the CMB anisotropies and the local (distance ladder) measurement from the Hubble Space Telescope (HST), based on Cepheids. In this work, we investigate the impact of the running vacuum model (RVM) and related models on such a controversy. For the RVM, the vacuum energy density $ρ_Λ$ carries a mild dependence on the cosmic expansion rate, i.e. $ρ_Λ(H)$, which allows to ameliorate the fit quality to the overall $SNIa+BAO+H(z)+LSS+CMB$ cosmological observations as compared to the concordance $Λ$CDM model. By letting the RVM to deviate from the vacuum option, the equation of state $w=-1$ continues to be favored by the overall fit. Vacuum dynamics also predicts the following: i) the CMB range of values for $H_0$ is more favored than the local ones, and ii) smaller values for $σ_8(0)$. As a result, a better account for the LSS structure formation data is achieved as compared to the $Λ$CDM, which is based on a rigid (i.e. non-dynamical) $Λ$ term.
description: Accepted for publication in Phys. Lett. B. Significantly extended discussion, two figures and references added
European Nuclear Disarmament: a study of transnational social movement strategy
Creators: name: Burke, Patrick
Publisher: name: University of Westminster
Year: 2004

description: This thesis is a study of an attempt to help create a transnational movement against the nuclear arms race and the Cold War in the 1980s. The attempt began with the drafting and launch of the Appeal for European Nuclear Disarmament in early 1980. The thesis describes and analyses the work of the British group, European Nuclear Disarmament, or END, which was founded in order to further the aims outlined in the Appeal. The thesis examines END's work in three, overlapping, geographical areas: Britain, where END acted mainly as a pressure group on and/or ginger group within CND in an attempt to internationalize - END-ize - its work; in Western Europe (including Britain), where END (with other Western peace groups) was trying to create and sustain enduring ties amongst Western peace groups; and across the East-West divide, where END was one of a number of groups that engaged in dialogue with independent forces in the Soviet bloc - while maintaining relations with the regimes - with the aim of creating some kind of pan-European alliance that would bring together above all these forces and Western peace groups. The study is conducted in terms of an explanatory framework that emphasizes the pre-existing networks out of which END emerged; the distinctive END worldview or 'frame' and the ways in which END supporters campaigned in its terms, tried to persuade others to adopt it, and/or adapted it - above all in dialogue with independent groups in the Soviet bloc; the resources and structure that helped determine the work END activists could do; the way in which this campaigning was shaped by END's relationship with other peace groups, in Britain above all CND; and the political opportunities and constraints that END activists faced. To date there has been no full-length study of END nor one that analyses the various dimensions of its campaign and how they shaped each other. This thesis thus aims to be a contribution to our knowledge of the West European peace movements of the 1980s; it also hopes to add to our understanding of transnational social-movement campaigning.
The pressure field beneath intense surface water wave groups
Creators: name: Slunyaev, A.
name: Pelinovsky, E.
name: Hsu, H. -C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A weakly-nonlinear potential theory is developed for the description of deep penetrating pressure fields caused by single and colliding wave groups of collinear waves due to the second-order nonlinear interactions. The result is applied to the representative case of groups with the sech-shape of envelope solitons in deep water. When solitary groups experience a head-on collision, the induced due to nonlinearity dynamic pressure may have magnitude comparable with the magnitude of the linear solution. It attenuates with depth with characteristic length of the group, which may greatly exceed the individual wave length. In general the picture of the dynamic pressure beneath intense wave groups looks complicated. The qualitative difference in the structure of the induced pressure field for unidirectional and opposite wave trains is emphasized.
MPEC 2023-P72 : 2023 PC1
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 PC1

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Generalization of Faddeev--Popov Rules in Yang--Mills Theories: N=3,4 BRST Symmetries
Creators: name: Reshetnyak, Alexander
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Representation Theory (math.RT)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 70G60, 70G65, 70G75, 70H45, 70H03, 81T30, 81T70

description: The Faddeev-Popov rules for quantization of theory with gauge group are generalized for case of nvariance of quantum actions, $S_N$, on N-parametric Abelian SUSY transformations with odd parameters $λ_p$, p=1,..,N and anticommuting generators $s_p$, for N=3,4 implying substitution of ghost fields N-plet, $C^p$ multipled on $λ_p$, instead of the parameter, $ξ$, of gauge transformations. Total configuration spaces for quantum theory of the same classical model coincide for N=3 ,4 cases. For N=3 transformations the superspace of irrep includes in addition 3 ghost $C^p$, 3 even $B^{pq}$ and odd $\hat{B}$ fields for p,q=1-3. It is shown for quantum action $S_{3}$ the gauge-fixing by adding to classical action of N=3-exact term requires 1 antighost $\bar{C}$, 3 even $B^{p}$ 3 odd $\hat{B}{}^p$ and Nakanishi--Lautrup fields. Action of N=3 transformations on the latter fields is found. The transformations appear by N=3 BRST ones for the vacuum functional, $Z_3(0) $. It is shown, the configuration space appears by irrep superspace for fields $Φ_4$ for N=4- transformations containing in addition to $A^μ$: (4+6+4+1) ghost-antighost $C^r$, even $B^{rs}$, odd $\hat{B}{}^r $ fields and B. Action $S_4$ is constructed by adding to classical action of N=4-exact with gauge boson $F_4$ as compared to gauge fermion $Ψ_3$ for N=3 case. Procedure is valid for any admissible gauge. The equivalence with $N=1$ BRST-invariant quantization method is explicitly found. Finite N=3,4 BRST transformations are derived from algebraic transformations. Respective Jacobians for field-dependent parameters are calculated. They imply the presence of corresponding modified Ward identity to be reduced to new (usual) Ward identities for constant parameters and describe the problem of gauge-dependence. Introduction into diagrammatic Feynman techniques for N=3,4 cases is suggested.
description: 51 pages, corrected typos, published version
Superposing pure quantum states with partial prior information
Creators: name: Dogra, Shruti
name: Thomas, George
name: Ghosh, Sibasish
name: Suter, Dieter
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The principle of superposition is an intriguing feature of Quantum Mechanics, which is regularly exploited at various instances. A recent work [PRL \textbf{116}, 110403 (2016)] shows that the fundamentals of Quantum Mechanics restrict the superposition of two arbitrary pure states of a quantum system, even though it is possible to superpose two quantum states with partial prior knowledge. The prior knowledge imposes geometrical constraints on the choice of input pure states. We discuss an experimentally feasible protocol to superpose multiple pure states of a $d$ dimensional quantum system and carry out an explicit experimental realization to superpose two single-qubit pure states on a two-qubit NMR quantum information processor.
description: 9 pages, 4 figures
MPEC 2023-P73 : 2023 PD1
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 PD1

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Scalar perturbations of nonsingular nonrotating black holes in conformal gravity
Creators: name: Toshmatov, Bobir
name: Bambi, Cosimo
name: Ahmedov, Bobomurat
name: Stuchlík, Zdeněk
name: Schee, Jan
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study scalar and electromagnetic perturbations of a family of nonsingular nonrotating black hole spacetimes that are solutions in a large class of conformally invariant theories of gravity. The effective potential for scalar perturbations depends on the exact form of the scaling factor. Electromagnetic perturbations do not feel the scaling factor, and the corresponding quasinormal mode spectrum is the same as in the Schwarzschild metric. We find that these black hole metrics are stable under scalar and electromagnetic perturbations. Assuming that the quasinormal mode spectrum for scalar perturbations is not too different from that for gravitational perturbations, we can expect that the calculation of the quasinormal mode spectrum and the observation with gravitational wave detectors of quasinormal modes from astrophysical black holes can constrain the scaling factor and test these solutions.
description: 10 pages, 5 figures, 3 tables
Technologies and Utopias: the cyberflâneur and the experience of being online
Creators: name: Hartmann, Maren
Publisher: name: University of Westminster
Year: 2004

description: The thesis examines the historical moment of the transition of the Internet from a technology to a cultural form with widespread social use. It is a moment that contains traces of the utopian dreams of the early users of the Internet at the point when it became a widely available, accessible everyday resource. I examine this moment of transition in terms of a vocabulary of use that sought to give expression to the then novel experience of being online. These conceptualisation of use are called user types and usually appear as metaphors. The first two chapters begin with metaphor, presented both in theory and in practice. This is followed by an introduction to cybercultural studies and cyberferninism, approaches which provide both inspiration and counterargument to the here presented approach. This framework is expanded in the fourth chapter, in which existing methodologies are outlined to introduce the virtual archaeology. This approach is inspired by the most important theoretical reference point for the thesis: Benjamin and his Arcades Project (and within that: cyberflAnerie). Benjamin's project emphasises the analysis of fragments, which are juxtaposed to illuminate an otherwise invisible meaning. Similar structures are seen to exist online. These shape the particularity of the creation of meaning. Another important aspect of Benjamin is his emphasis on the city and the radical shift of modernity. Each user type is seen to similarly express a reaction to the shock of the new, expressing particular utopian moments in Internet history. User types tell us something of the formation of discourses that complete the transformation of a technology from the technical into recognisable social and cultural identities. The user types analysed in detail are: the cyberflAneur, cyberfldneuse, webgrrl, cyberpunk, netizen, cybernaut and surfer. Their detailed analysis provides the second part of the thesis. The aspects referred to in the first part are all part of these analyses. Final reflections about the user types' role as specific communication tools, which shape the cultural form of the new medium, conclude the thesis.