cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Old main-sequence turnoff photometry in the SMC: Star Formation History and Chemical Enrichment Law
Creators: name: Noel, Noelia E. D.
name: Aparicio, Antonio
name: Gallart, Carme
name: Hidalgo, Sebastian L.
name: Carrera, Ricardo
name: Costa, Edgardo
name: Mendez, Rene A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present deep ground-based {\it B} and {\it R} observations of 12 fields in the Small Magellanic Cloud (SMC). The resulting color-magnitude diagrams (CMDs) reach the oldest main-sequence (MS) turnoff at M$_{R}$$\thicksim$3.5 and reveal the stellar population differences between the part of the galaxy facing the Large Magellanic Cloud (LMC) and an area on the opposite side. In the Southern part of the galaxy, we found that there are still intermediate-age stars as far as 4 kpc from the SMC center. The Chemical Enrichment History (CEH) in one of our SMC fields is also presented.
description: Contributed talk presented at: Stellar Populations as Building Blocks of Galaxies, Proceedings IAU Symposium No. 241, 2007
Multimodal Attention Fusion for Target Speaker Extraction
Creators: name: Sato, Hiroshi
name: Ochiai, Tsubasa
name: Kinoshita, Keisuke
name: Delcroix, Marc
name: Nakatani, Tomohiro
name: Araki, Shoko
Publisher: name: arXiv
Year: 2021
Subjects: subject: Audio and Speech Processing (eess.AS)
subject: Machine Learning (cs.LG)
subject: Sound (cs.SD)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Target speaker extraction, which aims at extracting a target speaker's voice from a mixture of voices using audio, visual or locational clues, has received much interest. Recently an audio-visual target speaker extraction has been proposed that extracts target speech by using complementary audio and visual clues. Although audio-visual target speaker extraction offers a more stable performance than single modality methods for simulated data, its adaptation towards realistic situations has not been fully explored as well as evaluations on real recorded mixtures. One of the major issues to handle realistic situations is how to make the system robust to clue corruption because in real recordings both clues may not be equally reliable, e.g. visual clues may be affected by occlusions. In this work, we propose a novel attention mechanism for multi-modal fusion and its training methods that enable to effectively capture the reliability of the clues and weight the more reliable ones. Our proposals improve signal to distortion ratio (SDR) by 1.0 dB over conventional fusion mechanisms on simulated data. Moreover, we also record an audio-visual dataset of simultaneous speech with realistic visual clue corruption and show that audio-visual target speaker extraction with our proposals successfully work on real data.
description: 7 pages, 5 figures
Bayesian Pairwise Comparison of High-Dimensional Images
Creators: name: Guha, Subharup
name: Qiu, Peihua
Publisher: name: Taylor & Francis
Year: 2025
Subjects: subject: Space Science
subject: Medicine
subject: Cell Biology
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Information Systems not elsewhere classified
subject: Mathematical Sciences not elsewhere classified

description: A fundamental task in the automated analysis of images is the development of effective image pair comparison techniques. For two high-dimensional images, a statistical method must automatically label them as “similar” or “different” depending on whether random error and spatial dependencies could account for the pixel-wise differences. We develop a Bayesian strategy by constructing a novel extension of Dirichlet processes called the spatial random partition model (sRPM). The process groups spatially proximal image pixels with similar intensities into clusters, thereby achieving dimension reduction in the large number of pixels. Next, we apply the sRPM-based analytical procedure to compare two images. The image comparison problem is formulated as a hypothesis test involving a univariate metric adaptive to spatial correlations and robust to random variability in the pixel intensities. To handle the computational burden, we foster a two-stage technique for MCMC analysis and hypothesis testing of image pairs. A simulation study analyzes artificial datasets and finds compelling evidence for the high accuracy of sRPM in image comparison. We demonstrate the effectiveness of the technique by statistically analyzing satellite image data. Supplementary materials for this article are available online.
An alternative preparation of organofunctionalized silica gels and their characterization by solid-state NMR spectroscopy
Creators: name: Zhang, Yugao
Publisher: name: University of British Columbia
Year: 2010

description: The theoretical consideration and experimental techniques required to obtain high -resolution solid-state NMR spectra of silica gels and their organofunctionalized derivatives are presented. A series of organofunctionalized silica gels has been prepared by the copolymerization of the two components, tetraethoxysilane (TEOS), (EtO)₄Si, and methyltriethoxysilane (MTES) (EtO)₃SiCH₃, which is an alternative to the conventional anchoring method. CP/MAS solid-state NMR techniques have been used to elucidate the structures of the organofunctionalized silica gels. The copolymerization method is superior to the anchoring method in that more functional groups can be incorporated into a silica gel matrix. CP/MAS solid-state NMR has been successfully applied in the investigation of the thermal stabilities of the functionalized silica gels as a complementary technique to the more traditional DSC technique and it has been concluded that in an inert gas (N₂) environment, the methyl groups on the methylsilica gel made by copolymerization method are more thermally stable to decomposition than that made by the anchoring method and both are much more stable than in a normal atmospheric environment. Two-dimensional heteronuclear ¹H-²⁹Si correlation NMR spectroscopy has been used to characterize three different types of modified silica gels; methylsilica gel prepared by the anchoring method; methylsilica gel prepared by the copolymerization method; and a mechanical mixture of silica gel and polymethylsiloxane. This technique successfully demonstrated the structural differences among the three materials which cannot be easily distinguished by other analytical techniques. It is shown that methylsilica gel prepared by the anchoring method consists of two distinct phases when the functional group loading is high (i.e., polymethylsiloxane built up "horizontally" on the surface of silica gel), and it is very like the mechanical mixture of silica gel and polymethylsiloxane. On the other hand, the methylsilica gel prepared by the copolymerization method consists of a distribution of the two components, i.e., there is no domain structure between silica gel and polymethylsiloxane. The methyl protons and hydroxyl protons in the functionalized silica gels were found to be sources of cross-polarization transfer to the Si(0-)₄ framework silicons, but the physically absorbed water does not contribute to this transfer.
A search for the third lensed image in JVAS B1030+074
Creators: name: Zhang, M.
name: Jackson, N.
name: Porcas, R. W.
name: Browne, I. W. A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Central gravitational image detection is very important for the study of the mass distribution of the inner parts ($\sim 100$ pc) of lens galaxies. However, the detection of such images is extremely rare and difficult. We present a 1.7-GHz High Sensitivity Array (HSA) observation of the double-image radio lens system B1030+074. The data are combined with archive VLBA and global-VLBI observations, and careful consideration is given to the effects of noise, {\sc clean}ing and self-calibration. An upper limit is derived for the strength of the central image of 180 $μ$Jy (90% confidence level), considerably greater than would have been expected on the basis of a simple analysis. This gives a lower limit of $\sim 10^3$ for the ratio of the brightest image to the central image. For cusped models of lens mass distributions, we have made use of this non-detection to constrain the relation between inner power-law slope $β$ of the lensing galaxy mass profile, and its break radius $r_b$. For $r_b>130$ pc the power-law slope is required to be close to isothermal ($β>1.8$). A flatter inner slope is allowed if a massive black hole is present at the centre of the lensing galaxy, but the effect of the black hole is small unless it is $\sim 10$ times more massive than that implied by the relation between black hole mass and stellar velocity dispersion. By comparing four epochs of VLBI observations, we also detected possible superluminal motion in the jet in the brighter A image. The B jet remains unresolved, as expected from a simple lens model of the system.
description: Accepted by MNRAS; 13 pages, 11 figures, 2 tables; some figures bitmapped
Likelihood Corrections for Two-way Models
Creators: name: Jochmans, Koen
name: Otsu, T
Publisher: name: Apollo - University of Cambridge Repository
Year: 2018
Subjects: asymptotic bias
bias correction
fixed effects
information bias
modified profile likelihood
panel data
MCMC
penalization
rectangular-array asymptotics

description: The use of panel data models with two-way fixed effects is widespread. Incidental-parameter bias, however, invalidates inference based on the (profile) likelihood. We consider modifications to the likelihood that yield asymptotically-unbiased estimators as well as test statistics that are size correct under rectangular-array asymptotics. The modifications are widely applicable and easy to implement. Through several examples we illustrate that the modifications can lead to dramatic improvements relative to maximum likelihood, both in terms of point estimation and inference.
ผลของธาตุผสมต่อความแข็งขณะทำกรรมวิธีทางความร้อนของเหล็กหล่อขาวที่เติมธาตุผสมหลายชนิด
Creators: name: รุจิภาส สีลาดเลา
Publisher: name: มหาวิทยาลัยมหาสารคาม
Year: 2557
Subjects: กรรมวิธีทางความร้อน, เหล็กหล่อขาวที่เติมธาตุผสมหลายชนิด, ความแข็ง, ธาตุผสม

description: ฉบับพิเศษ, วารสารวิทยาศาสตร์และเทคโนโลยี มหาวิทยาลัยมหาสารคาม
การใช้ข้อมูลภาพถ่ายดาวเทียมและเทคนิคการประมวลผลภาพสำหรับ การวิเคราะห์เมฆทางอุตุนิยมวิทยา
Creators: name: ธีรวงศ์ เหล่าสุวรรณ
Publisher: name: มหาวิทยาลัยมหาสารคาม
Year: 2557
Subjects: ภาพถ่ายดาวเทียม, เทคนิคการประมวลผลภาพ, การวิเคราะห์เมฆ

description: ฉบับพิเศษ, วารสารวิทยาศาสตร์และเทคโนโลยี มหาวิทยาลัยมหาสารคาม
ปัจจัยที่ส่งผลกระทบต่อประสิทธิภาพเชิงความร้อนและการปลดปล่อยแก๊สคาร์บอนมอนนอกไซด์ของเตาสนาม
Creators: name: จิระศักดิ์ ดงแสง
Publisher: name: มหาวิทยาลัยมหาสารคาม
Year: 2557
Subjects: เตาสนาม, คาร์บอนมอนอกไซด์, การทดสอบภาคสนาม, อินฟราเรด

description: ฉบับพิเศษ, วารสารวิทยาศาสตร์และเทคโนโลยี มหาวิทยาลัยมหาสารคาม
Conditions of Low Dimensionality for Strongly Interacting Atoms Under a Transverse Trap
Creators: name: Kestner, J. P.
name: Duan, L. -M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: For a dilute atomic gas in a strong transverse trapping potential, one normally expects that, in the ground state, the gas will populate only the lowest transverse level. We show, however, that for the strongly interacting gas under a Feshbach resonance, the ground state includes a large fraction of atoms in excited levels of the trap, even if the gas is very dilute and the trap is very strong. This is because the effective atom-molecule coupling is typically enhanced to many times the trap mode spacing by an induced confinement along the untrapped dimension(s). Thus one cannot ''freeze out'' the transverse degrees of freedom except under certain conditions.
description: 9 pages, 7 figures
การประมาณค่าดัชนีฤดูกาลในวิธีแยกส่วนประกอบด้วย GRG2
Creators: name: วฐา มินเสน
Publisher: name: มหาวิทยาลัยมหาสารคาม
Year: 2557
Subjects: การพยากรณ์, วีธีแยกส่วนประกอบ, เจเนอรัลรีดิวซ์เกรเดียน, โซลเวอร์

description: ฉบับพิเศษ, วารสารวิทยาศาสตร์และเทคโนโลยี มหาวิทยาลัยมหาสารคาม
Converged Colored Noise Path Integral Molecular Dynamics Study of the Zundel Cation down to Ultra-low Temperatures at Coupled Cluster Accuracy
Creators: name: Schran, Christoph
name: Brieuc, Fabien
name: Marx, Dominik
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: For a long time, performing converged path integral simulations at ultra-low, but finite temperatures of a few Kelvin has been a nearly impossible task. However, recent developments in advanced colored noise thermostatting schemes for path integral simulations, namely the Path Integral Generalized Langevin Equation Thermostat (PIGLET) and the Path Integral Quantum Thermal Bath (PIQTB), have been able to greatly reduce the computational cost of these simulations, thus making the ultra-low temperature regime accessible in practice. In this work, we investigate the influence of these two thermostatting schemes on the description of hydrogen-bonded systems at temperatures down to a few Kelvin as encountered, for example, in helium nanodroplet isolation or tagging photodissociation spectroscopy experiments. For this purpose, we analyze the prototypical hydrogen bond in the Zundel cation (H$_5$O$_{2}^{+}$) as a function of both, oxygen-oxygen distance and temperature in order to elucidate how the anisotropic quantum delocalization and, thus, the shape of the shared proton adapts depending on the donor-acceptor distance. The underlying electronic structure of the Zundel cation is described in terms of Behler's Neural Network Potentials of essentially converged Coupled Cluster accuracy, CCSD(T*)-F12a/AVTZ. In addition, the performances of the PIQTB and PIGLET methods for energetic, structural, and quantum delocalization properties are assessed and directly compared. Overall, our results emphasize the validity and practical usefulness of these two modern thermostatting approaches for path integral simulations of hydrogen-bonded systems even at ultra-low temperatures.
A Temporal Type-2 Fuzzy System for Time-dependent Explainable Artificial Intelligence
Creators: name: Kiani, Mehrin
name: Andreu-Perez, Javier
name: Hagras, Hani
Publisher: name: arXiv
Year: 2022
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences
subject: I.2; I.2.4
subject: 68T37, 68T01, 68T30

description: Explainable Artificial Intelligence (XAI) is a paradigm that delivers transparent models and decisions, which are easy to understand, analyze, and augment by a non-technical audience. Fuzzy Logic Systems (FLS) based XAI can provide an explainable framework, while also modeling uncertainties present in real-world environments, which renders it suitable for applications where explainability is a requirement. However, most real-life processes are not characterized by high levels of uncertainties alone; they are inherently time-dependent as well, i.e., the processes change with time. In this work, we present novel Temporal Type-2 FLS Based Approach for time-dependent XAI (TXAI) systems, which can account for the likelihood of a measurement's occurrence in the time domain using (the measurement's) frequency of occurrence. In Temporal Type-2 Fuzzy Sets (TT2FSs), a four-dimensional (4D) time-dependent membership function is developed where relations are used to construct the inter-relations between the elements of the universe of discourse and its frequency of occurrence. The TXAI system manifested better classification prowess, with 10-fold test datasets, with a mean recall of 95.40\% than a standard XAI system (based on non-temporal general type-2 (GT2) fuzzy sets) that had a mean recall of 87.04\%. TXAI also performed significantly better than most non-explainable AI systems between 3.95\%, to 19.04\% improvement gain in mean recall. In addition, TXAI can also outline the most likely time-dependent trajectories using the frequency of occurrence values embedded in the TXAI model; viz. given a rule at a determined time interval, what will be the next most likely rule at a subsequent time interval. In this regard, the proposed TXAI system can have profound implications for delineating the evolution of real-life time-dependent processes, such as behavioural or biological processes.
On Six Dimensional Fundamental Superstrings as Holograms
Creators: name: Alishahiha, Mohsen
name: Mukhopadhyay, Subir
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this note we discuss a possible holographic dual of the two dimensional conformal field theory associated with the world-sheet of a macroscopic superstring in a compactification on four-torus. We assume the near horizon geometry of the black string has symmetries of $AdS_3\times S^3\times T^4$ and construct a sigma model in the bulk. Analyzing the symmetries of the bulk theory and comparing them with those of the CFT in a special light-cone gauge we find agreement between global symmetries. Due to non-standard gauge realization it is not clear how affine symmetries can be realized.
description: 19 pages, LaTeX, minor corrections, typos corrected, version to appear in IJMPA
Experimental characterisation of a non-Markovian quantum process
Creators: name: Goswami, K.
name: Giarmatzi, C.
name: Monterola, C.
name: Shrapnel, S.
name: Romero, J.
name: Costa, F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Every quantum system is coupled to an environment. Such system-environment interaction leads to temporal correlation between quantum operations at different times, resulting in non-Markovian noise. In principle, a full characterisation of non-Markovian noise requires tomography of a multi-time processes matrix, which is both computationally and experimentally demanding. In this paper, we propose a more efficient solution. We employ machine learning models to estimate the amount of non-Markovianity, as quantified by an information-theoretic measure, with tomographically incomplete measurement. We test our model on a quantum optical experiment, and we are able to predict the non-Markovianity measure with $90\%$ accuracy. Our experiment paves the way for efficient detection of non-Markovian noise appearing in large scale quantum computers.
Heavy Calcium in CP Stars
Creators: name: Cowley, C. R.
name: Hubrig, S.
name: Castelli, F.
name: Gonzalez, J. F.
name: Wolff, B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Large wavelength shifts of infrared triplet lines of Ca II have been observed in the spectra of HgMn and magnetic Ap stars. They have been attributed to the heavy calcium isotopes, including Ca-48. One member of the triplet, $λ$8542, had been either unavailable, or of poor quality in earlier spectra. The present material shows conclusively that the stellar $λ$8542 shifts are consistent with an interpretation in terms of Ca-48. We find no relation between isotopic shifts of the Ca II triplet lines, and those of Hg II $λ$3984. There is a marginal indication that the shifts are {\it anticorrelated} with the surface field strengths of the magnetic stars. We see sparse evidence for Ca-48 in other chemically peculiar stars, e.g. Am's, metal-poor stars, or chemically peculiar red giants. However, the sample is still very small, and the wavelengths of all three triplet lines, including those in the Sun, show slight positive shifts with respect to terrestrial positions. Some profiles of the Ca II infrared triplet in the magnetic stars show extensive wings beyond a well-defined core. We can obtain reasonable fits to these profiles using a stratified calcium abundance similar to that used by previous workers. There is no indication that either the stratification or the Zeeman effect significantly disturbs the measurement of isotope shifts.
description: 10 Pages, 11 Figures. Accepted for publication in MNRAS
[Northern Pomo texts]
Creators: name: Guerrero, Edna
name: Vihman, Eero
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2015
Subjects: subject: pej
subject: Northern Pomo language

description: Northern Pomo notebook labeled "EG 19": previously elicited texts, with interlinear glosses and free translations. Titles "Indian villages in Potter Valley", "On food", "On customs", "Dances and rituals", "Kinship terms", "Dinner ritual", "On her relatives", "Coyote vomits a lake", "Coyote and Woodrat", "Coyote and the girls", "On son's death", "On basket making", "Flood story", "Anglos & Indians", "Anglos & Indian women", "Taboos", "On fishing", "Preparing sunflower seeds", "Visiting Monos I".
Dual character of the electronic structure in YBa2Cu4O8: conduction bands of CuO2 planes and CuO chains
Creators: name: Kondo, T.
name: Khasanov, R.
name: Karpinski, J.
name: Kazakov, S. M.
name: Zhigadlo, N. D.
name: Ohta, T.
name: Fretwell, H. M.
name: Palczewski, A. D.
name: Koll, J. D.
name: Mesot, J.
name: Rotenberg, E.
name: Keller, H.
name: Kaminski, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We use microprobe Angle-Resolved Photoemission Spectroscopy (muARPES) to separately investigate the electronic properties of CuO2 planes and CuO chains in the high temperature superconductor, YBa2Cu4O8. In the CuO2 planes, a two dimensional (2D) electronic structure with nearly momentum independent bilayer splitting is observed. The splitting energy is 150 meV at (pi,0), almost 50% larger than in Bi2Sr2CaCu2O(8+d) and the electron scattering at the Fermi level in the bonding band is about 1.5 times stronger than in the antibonding band. The CuO chains have a quasi one dimensional (1D) electronic structure. We observe two 1D bands separated by ~ 550meV: a conducting band and an insulating band with an energy gap of ~ 240meV. We find that the conduction electrons are well confined within the planes and chains with a non-trivial hybridization.
description: 4 pages, 4 figures
Mechanisms and consequences of flight polyphenisms in an outbreaking bark beetle species
Creators: Jones, Kelsey L.
Rajabzadeh, Rahmatollah
Ishangulyyeva, Guncha
Erbilgin, Nadir
Evenden, Maya L.
Publisher: name: University of Alberta Library
Year: 2020

Flight polyphenisms naturally occur as discrete or continuous traits in insects. Discrete flight polyphenisms include winged and wingless morphs, whereas continuous flight polyphenisms can take the form of short- or long-distance fliers. The mountain pine beetle (Dendroctonus ponderosae) exhibits polyphenic variation in flight distance but the consequences of this flight variation on life history strategies of beetles is unknown. This study assessed the effect of flight on two particular aspects of beetle biology: (1) an energetic trade-off between flight distance and host colonisation capacity; and (2) the relationship between flight distance and pheromone production. A 23 h flight treatment was applied to a subset of beetles using computer-linked flight mills. After flight treatment, both flown and unflown (control) beetles were given the opportunity to colonise bolts of host trees, and beetles that entered hosts were aerated to collect pheromone. A trade-off occurred between initiation of host colonisation and percentage body mass lost during flight, which indicates energy use during flight affects host acceptance in female mountain pine beetles. Furthermore, production of the aggregation pheromone trans-verbenol by female beetles was influenced by both percentage body mass lost during flight and flight distance. Male production of exo-brevicomin was affected by beetle condition following flight but not by the energy used during flight. These novel results give new insight into the polyphenic flight behaviour of mountain pine beetles. Flight variation is adaptive by acting to maintain population levels through safe and risky host colonisation strategies. These findings suggest mechanisms that facilitate the extremities of the continuous flight polyphenism spectrum. These opposing mechanisms appear to maintain the high variation in flight exhibited by this species.
Froehlich Polarons From 3D to 0D. Concepts and Recent Developments
Creators: name: Devreese, J. T.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: An overview is presented of the fundamentals of continuum-polaron physics, which provide the basis of the analysis of polaron effects in ionic crystals and polar semiconductors. The present paper deals with "large", or "continuum", polarons, as described by the Froehlich Hamiltonian. The emphasis is on the polaron optical absorption.
description: 26 pages, 14 figures, 2 tables
Colliding Particles in Highly Turbulent Flows
Creators: name: Mehlig, Bernhard
name: Uski, Ville
name: Wilkinson, Michael
Publisher: name: arXiv
Year: 2006
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We discuss relative velocities and the collision rate of small particles suspended in a highly turbulent fluid. In the limit where the viscous damping is very weak, we estimate the relative velocities using the Kolmogorov cascade principle.
description: 5 pages, no figures, v2 contains additional results
Two new chemically peculiar stars with resolved magnetically split lines
Creators: name: Hubrig, S.
name: Nesvacil, N.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report the discovery of resolved magnetically split lines in two chemically peculiar stars, the SrEuCr star HD 92499 and the Bp SiCr star HD 157751. From FEROS spectra, we have measured a mean magnetic field modulus of 8.5 kG for HD 92499 and a mean magnetic field modulus of 6.6 kG for HD 157751. Both stars have small projected rotational velocities: v sin i = 3.0 km/s and 8.5 km/s, respectively. Our preliminary abundance analysis reveals ionisation imbalance of rare earths in HD 92499 indicating the abundance pattern typical of rapidly oscillating Ap stars. Cr and Fe are found strongly overabundant in HD 157751.
description: 4 pages, 6 figures, 1 table, accepted for publication as a letter to MNRAS
Detection of variable Si II, Mn II and Fe II emission lines in the magnetic Bp star a Centauri
Creators: name: Hubrig, S.
name: Gonzalez, J. F.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The nature of non-variable high-excitation emission lines detected in the optical spectra of normal late-B type and chemically peculiar HgMn and PGa stars is still poorly understood. To better understand the origin of the weak emission lines in B type stars it is especially important to investigate the spectra of a variety of stars to search for correlations between the emergence of these lines and fundamental stellar parameters. We have acquired high resolution UVES spectra for the sharp-lined magnetic helium-variable star a Cen over the rotation period of 8.82 d to search for the presence of weak emission lines. For the first time we present observational evidence for the appearance of variable high-excitation Si II, Mn II and Fe II emission lines in a magnetic Bp star. Si II emissions are the strongest at the phase corresponding to the maximum strength of He I lines. Mn II and Fe II emissions vary in antiphase to the He I lines. A correlation is found between the probable location of Mn and Fe surface spots and the strength of the emission lines. On the basis of the currently available data it seems possible that the same kind of selective excitation process is working in the atmospheres of objects within a broad parameter space which could be defined by age, effective temperature, chemical composition, rotational velocity, and magnetic field. Neutral iron lines previously reported to appear broad and shallow at certain phases are not detected in our spectra, although two of them are identified as He I forbidden lines, showing maximum strength at the phase of the passage of the He rich region across the visible disk.
description: 5 pages, 6 figures, 1 table, accepted for publication in A&A
Exotic hadrons in s-wave chiral dynamics
Creators: name: Hyodo, Tetsuo
name: Jido, Daisuke
name: Hosaka, Atsushi
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study s-wave scattering of a hadron and a Nambu-Goldstone boson induced by the model-independent low energy interaction in the flavor SU(3) symmetric limit. Establishing the general structure of the low energy interaction based on group theoretical arguments, we find that the interaction in the exotic channels are in most cases repulsive, and that for possible attractive channels the interaction strengths are weak and uniquely given independent of channel. Solving the scattering problem with this interaction, we show that the attraction in the exotic channels is not strong enough to generate a bound state from the physically known target hadrons. We also find that there are no attractive interaction in the exotic channels in large Nc limit.
description: RevTeX4, 4 pages, 1 figure, 2 tables, typos corrected
Transition from a one-dimensional to a quasi-one-dimensional state in interacting quantum wires
Creators: name: Meyer, Julia S.
name: Matveev, K. A.
name: Larkin, A. I.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Upon increasing the electron density in a quantum wire, the one-dimensional electron system undergoes a transition to a quasi-one-dimensional state. In the absence of interactions between electrons, this corresponds to filling up the second subband of transverse quantization, and there are two gapless excitation modes above the transition. On the other hand, strongly interacting one-dimensional electrons form a Wigner crystal, and the transition corresponds to it splitting into two chains (zigzag crystal). The two chains are locked, so their relative motion is gapped, and only one gapless mode remains. We study the evolution of the system as the interaction strength changes, and show that only one gapless mode exists near the transition at any interaction strength.
description: 4 pages, 2 figures
Phonons in honeycomb and auxetic two-dimensional lattices
Creators: name: Sparavigna, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The modes of vibrations in honeycomb and auxetic structures are studied, with models in which the lattice is represented by a planar network where sites are connected by strings and rigid rods. The auxetic network is obtained modifying a model proposed by Evans et al. in 1991, and used to explain the negative Poisson's ratio of auxetic materials. This relevant property means that the materials have a lateral extension, instead to shrink, when they are stretched. For what concerns the acoustic properties of these structures, they absorb noise and vibrations more efficiently than non-auxetic equivalents. The acoustic and optical dispersions obtained in the case of the auxetic model are compared with the dispersions displayed by a conventional honeycomb network. It is possible to see that the phonon dispersions of the auxetic model possess a complete bandgap and that the Goldstone mode group velocity is strongly dependent on the direction of propagation. The presence of a complete bandgap can explain some experimental observations on the sound propagation properties of the auxetic materials.
description: 12 pages, 6 figures
The Sybils' Advice on Charm (and $τ$ Leptons)
Creators: name: Bigi, I. I.
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The importance of future studies of charm and $τ$ decays is emphasized as probes of New Physics: the most powerful tools are \cp asymmetries in charm and $τ$ decays both in partial widths and final state distributions. While these searches for \cp violation are instrumentalized in the search for and hopefully future analysis of New Physics, they might also shed light on the \cp breaking dynamics required to implement baryogenesis. $e^+e^-$ Super-Flavour Factories are optimally suited for the challenge, in many aspects even uniquely so.
description: 11 pages, 2 figures; Invited Talk given at DIF06, LNF, Frascati, Italy, Feb. 28 - March 3, 2006
Measurement of air fluorescence light yield induced by an electromagnetic shower
Creators: name: Colin, P.
name: Chukanov, A.
name: Grebenyuk, V.
name: Naumov, D.
name: Nedelec, P.
name: Nefedov, Yu.
name: Onofre, A.
name: Porokhovoi, S.
name: Sabirov, B.
name: Tkatchev, L.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: For most of the Ultra-High-Energy-Cosmic-Ray (UHECR) experiments and projects (HiRes, AUGER, TA, JEM-EUSO, TUS,...), the detection technique of Extensive Air Showers is based, at least, on the measurement of the air-fluorescence-induced signal. The knowledge of the Fluorescence-Light Yield (FLY) is of paramount importance for the UHECR energy reconstruction. The MACFLY experiment was designed to perform absolute measurements of the air FLY and to study its properties. Here, we report the result of measurement of dry-air FLY induced by 50 GeV electromagnetic showers as a function of the shower age and as a function of the pressure. The experiment was performed at CERN using a SPS-electron-test-beam line. The result shows the air FLY is proportional to the energy deposited in air (E_d). The ratio FLY/E_d and its pressure dependence remain constant independently of shower age, and more generally, independently of the excitation source used (single-electron track or air shower).
description: 12 pages, 6 figures, accepted for publication in Astropart. phys
The chemistry of thujone : the synthesis of rose oil components and germacrane analogues
Creators: name: Gunning, Philip James
Publisher: name: University of British Columbia
Year: 2011

description: This thesis is concerned with the synthesis of natural products from thujone (1), a readily available starting material obtained from Western red cedar. The first part of this study investigates the synthesis of the commercially important fragrances, (β-damascone (8) and β-damascenone (24), which are components of rose oil. Thujone can be efficiently converted to the dimethylated thujone derivative 59 in a two step alkylation process. After the formation of the trimethylsilyl cyanohydrins, 77 and 78, the cyclopropane and isopropyl functionalities were cleaved to give the ketone 103. Further elaboration of 103 gave the key intermediates, 127 and 128. The unsaturated nitriles 128 and 127 can be converted to 8 and 24, respectively, by a reduction to the corresponding aldehydes followed by a Grignard reaction to attach the side-chain and subsequent oxidation. As a model study for the synthesis of 8 and 24 from a cyclohexanone derivative, the nitriles 127 and 128 were efficiently synthesised, in 81% overall yield, from 2,2,6-trimethylcyclohexanone. Formation of the cyanohydrins 149 and 150 was followed by consecutive 'trans' and 'cis' eliminations to give the nitrile 128. The nitrile 127 was produced from 128 by allylic bromination, followed by hydrolysis and dehydration. A conversion of thujone into the ketone 179, using bromine to effect cyclopropane ring-opening, was also studied. The second part of this study investigates the synthesis of ten-membered rings via a photo-induced oxidative cleavage of the alcohols 245 and 265. Treatment of 245 with lead tetraacetate under ultraviolet irradiation afforded, as the main isolated product, the ten-membered carbocycle 246. Treatment of 265 with iodobenzene diacetate under ultraviolet irradiation afforded, as the main isolated product, the bicyclic alcohol 297. [diagrams omitted]
Energy spectra of gamma-rays, electrons and neutrinos produced at interactions of relativistic protons with low energy radiation
Creators: name: Kelner, S. R.
name: Aharonian, F. A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We derived simple analytical parametrizations for energy distributions of photons, electrons, and neutrinos produced in interactions of relativistic protons with an isotropic monochromatic radiation field. The results on photomeson processes are obtained using numerical simulations of proton-photon interactions based on the public available Monte-Carlo code SOPHIA. For calculations of energy spectra of electrons and positrons from the pair production (Bethe-Heitler) process we suggest a simple formalism based on the well-known differential cross-section of the process in the rest frame of the proton. The analytical presentations of energy distributions of photons and leptons provide a simple but accurate approach for calculations of broad-band energy spectra of gamma-rays and neutrinos in cosmic proton accelerators located in radiation dominated environments.
description: 17 pages, 21 figures, published in Phys.Rev.D. We have corrected two misprints in the text. We note that the correct expressions were used for calculations in the previous versions of the paper, thus the misprints did not have an impact on the figures
[Northern Pomo texts]
Creators: name: Lake, Annie
name: Vihman, Eero
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2015
Subjects: subject: pej
subject: Northern Pomo language

description: Northern Pomo notebook labeled "AL 18": previously elicited texts, with interlinear glosses and free translations. Titles "How Coyote broke his back", "Flushing deer", "Crying deer", "Small deer", "Drowning of bobcat", "Why rattlesnakes ...", "Negroes stealing grapes", "Grandmother talking to the rabbit", "Drilling fire", "Shells & beads", "Bird women", "Crying dove", "2 men from Tule Lake", "Bear man", "Woodpecker & Worm Woman", "Basket making".
Spin Accumulation in the Electron Transport with Rashba Interaction
Creators: name: Chin, Yi-Ying
name: Chiu, Jui-Yu
name: Chang, Ming-Che
name: Mou, Chung-Yu
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The non-equilibrium transportation of two-dimensional electrons through a narrow channel is investigated under the influence of the Rashba interaction. By introducing suitable lifetime in the Green's function, the average spin values can be calculated from the ballistic regime to the diffusive regime. It is shown that the spin accumulation is a combined effect of the spin current and disorders. In the diffusive regime, disorders offer a mechanism to stop the spin current and generate the spin accumulation. In the ballistic regime, spins are more spread out and do not have definite signs. Further consideration indicates that the inclusion of ferromagnetic spin-spin interaction increases the spin accumulation near the edge.
description: 2 pages, 2 figures, to appear in Journal of magnetism and magnetic materials
Boundary correlation function of fixed-to-free bcc operators in square-lattice Ising model
Creators: name: Lee, Seung-Yeop
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We calculate the boundary correlation function of fixed-to-free boundary condition changing operators in the square-lattice Ising model. The correlation function is expressed in four different ways using $2\times2$ block Toeplitz determinants. We show that these can be transformed into a scalar Toeplitz determinant when the size of the matrix is even. To know the asymptotic behavior of the correlation function at large distance we calculate the asymptotic behavior of this scalar Toeplitz determinant using the Szegö's theorem and the Fisher-Hartwig theorem. At the critical temperature we confirm the power-law behavior of the correlation function predicted by conformal field theory.
The Value of Communication and Cooperation in a Two-Server Service System
Creators: name: Fackrell, Mark
name: Li, Cong
name: Taylor, Peter
name: Wang, Jiesen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Science and Game Theory (cs.GT)
subject: Probability (math.PR)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: In 2015, Guglielmi and Badia discussed optimal strategies in a particular type of service system with two strategic servers. In their setup, each server can either be active or inactive and an active server can be requested to transmit a sequence of packets. The servers have varying probabilities of successfully transmitting when they are active, and both servers receive a unit reward if the sequence of packets is transmitted successfully. Guglielmi and Badia provided an analysis of optimal strategies in four scenarios: where each server does not know the other's successful transmission probability; one of the two servers is always inactive; each server knows the other's successful transmission probability; and they are willing to cooperate. Unfortunately the analysis in Guglielmi and Badia contained errors. In this paper we correct these errors. We discuss three cases where both servers (I) communicate and cooperate; (II) neither communicate nor cooperate; (III) communicate but do not cooperate. In particular, we obtain the unique Nash equilibrium strategy in Case II through a Bayesian game formulation, and demonstrate that there is a region in the parameter space where there are multiple Nash equilibria in Case III. We also quantify the value of communication or cooperation by comparing the social welfare in the three cases, and propose possible regulations to make the Nash equilibrium strategy the socially optimal strategy for both Cases II and III.
description: 25 pages, 7 figures
Neutral Bound States in Kink-like Theories
Creators: name: Mussardo, Giuseppe
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Other Condensed Matter (cond-mat.other)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: In this paper we present an elementary derivation of the semi-classical spectrum of neutral particles in a field theory with kink excitations. In the non-integrable cases, we show that each vacuum state cannot generically support more than two stable particles, since all other neutral exitations are resonances, which will eventually decay. A phase space estimate of these decay rates is also given. This shows that there may be a window of values of the coupling constant where a particle with higher mass is more stable than the one with lower mass. We also discuss the crossing symmetry properties of the semiclassical form factors and the possibility of extracting the elastic part of the kink $S$-matrix below their inelastic threshold. We present the analysis of theories with symmetric and asymmetric wells, as well as of those with symmetric or asymmetric kinks. Illustrative examples of such theories are provided, among others, by the Tricritical Ising Ising, the Double Sine Gordon model and by a class of potentials recently introduced by Bazeira et al.
description: 68 pages, 30 figures
Lagrangian approach to sheaves of vertex algebras
Creators: name: Malikov, F.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Algebraic Geometry (math.AG)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We explain how sheaves of vertex algebras are related to mathematical structures encoded by a class of Lagrangians. The exposition is focused on two examples: the WZW model and the (1,1)-supersymmetric $σ$-model. We conclude by showing how to construct a family of vertex algebras with base the Barannikov-Kontsevich moduli space.
A mercantilização do ensino superior no Brasil
Creators: name: Mota Júnior, Antônio de Macêdo
name: Sousa, Joelson Pereira de
Publisher: name: figshare
Year: 2021
Subjects: subject: 130103 Higher Education
subject: FOS: Educational sciences

description: O presente estudo exploratório, bibliográfico e documental aborda o tema da mercantilização do ensino superior no Brasil, com o objetivo de caracterizar o processo de mercantilização e de financiamento público da rede privada de ensino superior no país, justificado por um contexto de intensa circulação do discurso de crise na educação brasileira e de desvalorização das universidades públicas. Os resultados evidenciaram um célere processo de financeirização, oligopolização e transnacionalização, que configura o cenário atual de mercantilização do ensino superior brasileiro. Esse processo também é influenciado por pressões políticas à massificação da oferta, caracterizado por transferências de recursos públicos que financiam a iniciativa privada, especialmente em duas frentes, o financiamento estudantil e as isenções fiscais.
Impacts of Extreme Temperature on the Tilapia Value Chain from Pond Culture in Luzon, Philippines
Creators: name: Ramirez, Paul Joseph B.
name: Lansangan, Edilyn V.
name: Tubal, Jairus Jesse M.
name: Catelo, Salvador P.
name: Ramirez, Paul Joseph B.
name: Lansangan, Edilyn V.
name: Tubal, Jairus Jesse M.
name: Catelo, Salvador P.
Publisher: name: Unknown
Year: 2019
Subjects: subject: Environmental Economics and Policy
subject: climate change impacts
subject: extreme temperature
subject: value chain
subject: tilapia pond culture

description: The paper analyzed the impacts of extreme temperature on economic activities of selected value chain players in Luzon, Philippines. Direct impacts through decreased production and/or defensive expenditures and indirect effects on other chain players were estimated. Using the value chain approach, the economic viability of value chain activities and the associated risks were highlighted. Data were collected mainly through key informant interviews with key players in each node of the chain, local government units, agencies, and other stakeholders. Results show that direct impacts of extreme temperature are largest in the production segments of the value chain, with losses manifested either through reduced volume in tilapia produced/traded or diminished value due to smaller sized tilapia being harvested. While the share in value added of pond culture operators is the largest among players, they also bear the highest share in risk and losses in the face of climate change hazards.