cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The robustness of tests for autocorrelation in the dynamic linear regression model
Creators: name: Grant, Margaret.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Noise-induce coexisting firing patterns in hybrid-synaptic interacting networks
Creators: name: Wang, Xinyi
name: Zhang, Xiyun
name: Zheng, Muhua
name: Xu, Leijun
name: Xu, Kesheng
Publisher: name: arXiv
Year: 2022
Subjects: subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: Synaptic noise plays a major role in setting up coexistence of various firing patterns, but the precise mechanisms whereby these synaptic noise contributes to coexisting firing activities are subtle and remain elusive. To investigate these mechanisms, neurons with hybrid synaptic interaction in a balanced neuronal networks have been recently put forward. Here we show that both synaptic noise intensity and excitatory weights can make a greater contribution than variance of synaptic noise to the coexistence of firing states with slight modification parameters. The resulting statistical analysis of both voltage trajectories and their spike trains reveals two forms of coexisting firing patterns: time-varying and parameter-varying multistability. The emergence of time-varying multistability as a format of metstable state has been observed under suitable parameters settings of noise intensity and excitatory synaptic weight. While the parameter-varying multistability is accompanied by coexistence of synchrony state and metastable (or asynchronous firing state) with slightly varying noise intensity and excitatory weights. Our results offer a series of precise statistical explanation of the intricate effect of synaptic noise in neural multistability. This reconciles previous theoretical and numerical works, and confirms the suitability of various statistical methods to investigate multistability in a hybrid synaptic interacting neuronal networks.
description: 15 pages,8 figures
A semantic approach to nonmonotonic reasoning: Inference operations and choice
Creators: name: Lindström, Sten
Publisher: name: Universität Regensburg
Year: 2022
Subjects: subject: 100 Philosophie

description: This paper presents a uniform semantic treatment of nonmonotonic inference operations that allow for inferences from infinite sets of premisses. The semantics is formulated in terms of selection functions and is a generalisation of the preferential semantics of Shoham, Kraus et al., and Makinson. A selection function picks out from a given set of possible states (worlds, situations, models) a subset consisting of those states that are, in some sense, the most preferred ones. A proposition α is a nonmonotonic consequence of a set of propositions Γ iff α holds in all the most preferred Γ-states. In the literature on revealed preference theory, there are a number of well-known theorems concerning the representability of selection functions, satisfying certain properties, in terms of underlying preference relations. Such theorems are utilised here to give corresponding representation theorems for nonmonotonic inference operations. At the end of the paper, the connection between nonmonotonic inference and belief revision, in the sense of Alchourrón, Gärdenfors, and Makinson, is explored. In this connection, infinitary belief revision operations, that allow for the revision of a theory with a possibly infinite set of propositions, are introduced and characterised axiomatically. Several semantic representation theorems are proved for operations of this kind.
Non-coplanar magnetism, topological density wave order and emergent symmetry at half-integer filling of moiré Chern bands
Creators: name: Wilhelm, Patrick H.
name: Lang, Thomas C.
name: Scheurer, Mathias S.
name: Läuchli, Andreas M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Twisted double- and mono-bilayer graphene are graphene-based moiré materials hosting strongly correlated fermions in a gate-tunable conduction band with a topologically non-trivial character. Using unbiased exact diagonalization complemented by unrestricted Hartree-Fock calculations, we find that the strong electron-electron interactions lead to a non-coplanar magnetic state, which has the same symmetries as the tetrahedral antiferromagnet on the triangular lattice and can be thought of as a skyrmion lattice commensurate with the moiré scale, competing with a set of ferromagnetic, topological charge density waves featuring an approximate emergent O(3) symmetry, "rotating" the different charge density wave states into each other. Direct comparison with exact diagonalization reveals that the ordered phases are accurately described within the unrestricted Hartree-Fock approximation. Exhibiting a finite charge gap and Chern number $|C|=1$, the formation of charge density wave order which is intimately connected to a skyrmion lattice phase is consistent with recent experiments on these systems.
description: 35 pages, 12 figures
A broadband X-ray imaging spectroscopy in the 2030s: the FORCE mission
Creators: name: Mori, Koji
name: Tsuru, Takeshi G.
name: Nakazawa, Kazuhiro
name: Ueda, Yoshihiro
name: Watanabe, Shin
name: Tanaka, Takaaki
name: Ishida, Manabu
name: Matsumoto, Hironori
name: Awaki, Hisamitsu
name: Murakami, Hiroshi
name: Nobukawa, Masayoshi
name: Takeda, Ayaki
name: Fukazawa, Yasushi
name: Tsunemi, Hiroshi
name: Takahashi, Tadayuki
name: Hornschemeier, Ann
name: Okajima, Takashi
name: Zhang, William W.
name: Williams, Brian J.
name: Venters, Tonia
name: Madsen, Kristin
name: Yukita, Mihoko
name: Akamatsu, Hiroki
name: Bamba, Aya
name: Enoto, Teruaki
name: Fujita, Yutaka
name: Furuzawa, Akihiro
name: Hagino, Kouichi
name: Ishimura, Kosei
name: Itoh, Masayuki
name: Kitayama, Tetsu
name: Kobayashi, Shogo
name: Kohmura, Takayoshi
name: Kubota, Aya
name: Mizumoto, Misaki
name: Mizuno, Tsunefumi
name: Nakajima, Hiroshi
name: Nobukawa, Kumiko K.
name: Noda, Hirofumi
name: Odaka, Hirokazu
name: Ota, Naomi
name: Sato, Toshiki
name: Shidatsu, Megumi
name: Suzuki, Hiromasa
name: Takahashi, Hiromitsu
name: Tanimoto, Atsushi
name: Terada, Yukikatsu
name: Terashima, Yuichi
name: Uchida, Hiroyuki
name: Uchiyama, Yasunobu
name: Yamaguchi, Hiroya
name: Yatsu, Yoichi
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: In this multi-messenger astronomy era, all the observational probes are improving their sensitivities and overall performance. The Focusing on Relativistic universe and Cosmic Evolution (FORCE) mission, the product of a JAXA/NASA collaboration, will reach a 10 times higher sensitivity in the hard X-ray band ($E >$ 10~keV) in comparison with any previous hard X-ray missions, and provide simultaneous soft X-ray coverage. FORCE aims to be launched in the early 2030s, providing a perfect hard X-ray complement to the ESA flagship mission Athena. FORCE will be the most powerful X-ray probe for discovering obscured/hidden black holes and studying high energy particle acceleration in our Universe and will address how relativistic processes in the universe are realized and how these affect cosmic evolution. FORCE, which will operate over 1--79 keV, is equipped with two identical pairs of supermirrors and wideband X-ray imagers. The mirror and imager are connected by a high mechanical stiffness extensible optical bench with alignment monitor systems with a focal length of 12~m. A light-weight silicon mirror with multi-layer coating realizes a high angular resolution of $<15''$ in half-power diameter in the broad bandpass. The imager is a hybrid of a brand-new SOI-CMOS silicon-pixel detector and a CdTe detector responsible for the softer and harder energy bands, respectively. FORCE will play an essential role in the multi-messenger astronomy in the 2030s with its broadband X-ray sensitivity.
description: 12 pages, 8 figures. Proceedings of SPIE Astronomical Telescopes and Instrumentation 2022
Modelling the portfolio behaviour of the Australian authorised short-term money market
Creators: name: Ngui, Michael V. F.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Supplementary_Information.pdf from The swim-and-sink behaviour of copepods: a revisit to mechanical power requirement and a new hypothesis on function
Creators: name: Jiang, Houshuo
Publisher: name: The Royal Society
Year: 2023
Subjects: subject: Ecology
subject: FOS: Biological sciences
classificationCode: 110601
subject: Biomechanics
classificationCode: 60801
subject: Animal Behaviour

description: Many copepods display a swim-and-sink behaviour, which is not energetically efficient but likely aids in perceiving and capturing diatom chains. Here, computational fluid dynamics was employed to calculate the mechanical power required by a negatively buoyant, self-propelled copepod in swim-and-sink versus hovering. The results show that upward swim-and-sink about a fixed depth always demands more power than hovering. Subsequently, high-speed microscale imaging was employed to observe the copepod Centropages sp. in swim-and-sink, specifically its encounter and handling of diatom chains for capture, along with the measured alternating swimming and sinking currents imposed by the swim-and-sink copepod. The findings suggest that during upward swimming, the copepod uses its swimming current to scan the fluid for detecting embedded diatom chains, presumably through chemoreception. Once a diatom chain is perceived, the copepod sinks and uses its sinking current to manipulate the orientation of the diatom chain before swimming upward to capture it. Overall, these results propose a hypothesis that swim-and-sink is an innate behaviour that assists copepods in perceiving and manoeuvring diatom chains for capture. In contrast with near-spherical algae, diatom chains predominately exhibit a horizontal orientation in the ocean, necessitating vertically oriented copepods to possess a handling behaviour that manoeuvres diatom chains for capture.
MPEC 2023-P83 : DAILY ORBIT UPDATE (2023 August 15)
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

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.
Theory for Spin Selective Andreev Reflection in Vortex Core of Topological Superconductor: Majorana Zero Modes on Spherical Surface and Application to Spin Polarized Scanning Tunneling Microscope Probe
Creators: name: Hu, Lun-Hui
name: Li, Chuang
name: Xu, Dong-Hui
name: Zhou, Yi
name: Zhang, Fu-Chun
Publisher: name: arXiv
Year: 2016
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Majorana zero modes (MZMs) have been predicted to exist in the topological insulator (TI)/superconductor (SC) heterostructure. Recent spin polarized scanning tunneling microscope (STM) experiment$^{1}$ has observed spin-polarization dependence of the zero bias differential tunneling conductance at the center of vortex core, which may be attributed to the spin selective Andreev reflection, a novel property of the MZMs theoretically predicted in 1-dimensional nanowire$^{2}$. Here we consider a helical electron system described by a Rashba spin orbit coupling Hamiltonian on a spherical surface with a s-wave superconducting pairing due to proximity effect. We examine in-gap excitations of a pair of vortices with one at the north pole and the other at the south pole. While the MZM is not a spin eigenstate, the spin wavefunction of the MZM at the center of the vortex core, r = 0, is parallel to the magnetic field, and the local Andreev reflection of the MZM is spin selective, namely occurs only when the STM tip has the spin polarization parallel to the magnetic field, similar to the case in 1-dimensional nanowire2. The total local differential tunneling conductance consists of the normal term proportional to the local density of states and an additional term arising from the Andreev reflection. We also discuss the finite size effect, for which the MZM at the north pole is hybridized with the MZM at the south pole. We apply our theory to examine the recently reported spin-polarized STM experiments and show good agreement with the experiments.
description: 14 pages, 14 figures, 1 table. Comments are welcome!
A Monte Carlo Simulation Study of L-band Emission upon Gamma Radiolysis of Water
Creators: name: Kumar, K A Pradeep
name: Sundaram, G A Shanmugha
name: Venkatesh, S
name: Thiruvengadathan, R
Publisher: name: arXiv
Year: 2022
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Several studies have confirmed visible light and ultraviolet emission during water molecule radiolysis.However radiofrequency (RF) emissions have been scarcely investigated.This simulation study has revealed that the gamma radiolysis of water creates excited hydrogen atoms which emit radio recombination Lband (1 GHz to 2 GHz) radio waves of sufficient strength that a radio-imaging device can detect.The physical and physicochemical stages of radiolysis of water have been modeled via application of Monte Carlo simulation techniques up to 1ps from the onset of gamma photon interaction with water molecules.
Lyapunov-like functions involving Lie brackets
Creators: name: Motta, Monica
name: Rampazzo, Franco
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 34A26, 93D30, 93C15

description: For a given closed target we embed the dissipative relation that defines a control Lyapunov function in a more general differential inequality involving Hamiltonians built from iterated Lie brackets. The solutions of the resulting extended relation, here called degree-k control Lyapunov functions (k>=1), turn out to be still sufficient for the system to be globally asymptotically controllable to the target. Furthermore, we work out some examples where no standard (i.e., degree-1) smooth control Lyapunov functions exist while a smooth degree-k control Lyapunov function does exist, for some k>1. The extension is performed under very weak regularity assumptions on the system, to the point that, for instance, (set valued) Lie brackets of locally Lipschitz vector fields are considered as well.
Revealing the dynamics of magnetosphere, atmosphere, and interior of solar system objects with the Square Kilometre Array
Creators: name: Kimura, Tomoki
name: Fujii, Yuka
name: Kita, Hajime
name: Tsuchiya, Fuminori
name: Sagawa, Hideo
name: Team, the SKA-Japan Planetary Science
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Bodies such as planets, moons, and asteroids in our solar system are the brightest objects in the low-frequency radio astronomy at $\lesssim$ 10 GHz. The low-frequency radio emissions from our solar system bodies exhibit various observed characteristics in the spectrum, polarization, periodicity, and flux. The observed characteristics are essential probes for explorations of the bodies' magnetosphere, atmosphere, surface, and even their interior. Generation and propagation theories of the radio emissions associate the characteristics with fundamental physics embedded in the environments: e.g., auroral electron acceleration, betatron acceleration, and atmospheric momentum transfer. Here we review previous studies on the low-frequency radio emissions from our solar system bodies to unveil some outstanding key questions on the dynamics and evolution of the bodies. To address the key questions by the future observations with the Square Kilometre Array (SKA), we made feasibility studies for detection and imaging of the radio emissions. Possible extensions of the solar system observations with SKA to the exoplanets are also proposed in the summary.
Study of human accessibility: physical tests versus numerical simulation
Creators: name: Delangle, Mathieu
name: Poirson, Émilie
name: Petiot, Jean François
Publisher: name: arXiv
Year: 2016
Subjects: subject: Other Quantitative Biology (q-bio.OT)
subject: FOS: Biological sciences

description: Consideration of physical dimensions of the user population is essential to design adapted environment. This variability in body dimensions (called "anthropometry") is involved in design tools commonly used today to assess user's accommodation (physical mock-ups, population models, database, boundary manikins, hybrid methods or digital human modeling). Databases are created from campaigns of measurement. Besides the fact that such measures are costly in time and money, they give more "static" measures of man. They do not take into account possible stretching limbs that could allow increased accessibility. This paper presents a methodology for human body modeling, in a dynamic way, not static. The methodology allows to highlight influences of design and human behaviour on reach skills, directly induced by the interaction with real prototypes and not just considered by human physical dimensions. The first part of the method is to create a database of measurements (arms length, hip breadth, etc.). From these data, a model of accessibility is proposed. The accessibility field is determined purely numerically. In parallel, an experiment is set up to measure the extension of the accessibility field, with the same people. A comparison of the results is then performed and a new model of the human body is proposed.
Supplemental Materials for "Language and Postsecondary Trajectories: How 'Ever-English Learner' Status Predicts College Student Pathways and Outcomes"
Creators: name: Schudde, Lauren
name: Callahan, Rebecca
name: Kwon, Yujin
Publisher: name: The University of Texas at Austin
Year: 2024
Subjects: Ever-EL, English Learner, language, college student, postsecondary, student success, regression analysis

description: Supplemental materials (Appendix A & B) for manuscript: "Language and Postsecondary Trajectories: How 'Ever-English Learner' Status Predicts College Student Pathways and Outcomes"
Video_captions.docx from The swim-and-sink behaviour of copepods: a revisit to mechanical power requirement and a new hypothesis on function
Creators: name: Jiang, Houshuo
Publisher: name: The Royal Society
Year: 2023
Subjects: subject: Ecology
subject: FOS: Biological sciences
classificationCode: 110601
subject: Biomechanics
classificationCode: 60801
subject: Animal Behaviour

description: Many copepods display a swim-and-sink behaviour, which is not energetically efficient but likely aids in perceiving and capturing diatom chains. Here, computational fluid dynamics was employed to calculate the mechanical power required by a negatively buoyant, self-propelled copepod in swim-and-sink versus hovering. The results show that upward swim-and-sink about a fixed depth always demands more power than hovering. Subsequently, high-speed microscale imaging was employed to observe the copepod Centropages sp. in swim-and-sink, specifically its encounter and handling of diatom chains for capture, along with the measured alternating swimming and sinking currents imposed by the swim-and-sink copepod. The findings suggest that during upward swimming, the copepod uses its swimming current to scan the fluid for detecting embedded diatom chains, presumably through chemoreception. Once a diatom chain is perceived, the copepod sinks and uses its sinking current to manipulate the orientation of the diatom chain before swimming upward to capture it. Overall, these results propose a hypothesis that swim-and-sink is an innate behaviour that assists copepods in perceiving and manoeuvring diatom chains for capture. In contrast with near-spherical algae, diatom chains predominately exhibit a horizontal orientation in the ocean, necessitating vertically oriented copepods to possess a handling behaviour that manoeuvres diatom chains for capture.
UNIONS: The impact of systematic errors on weak-lensing peak counts
Creators: name: Ayçoberry, Emma
name: Ajani, Virginia
name: Guinot, Axel
name: Kilbinger, Martin
name: Pettorino, Valeria
name: Farrens, Samuel
name: Starck, Jean-Luc
name: Gavazzi, Raphaël
name: Hudson, Michael J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: UNIONS is an ongoing deep photometric multi-band survey of the Northern sky. As part of UNIONS, CFIS provides r-band data which we use to study weak-lensing peak counts for cosmological inference. We assess systematic effects for weak-lensing peak counts and their impact on cosmological parameters for the UNIONS survey. In particular, we present results on local calibration, metacalibration shear bias, baryonic feedback, the source galaxy redshift estimate, intrinsic alignment, and the cluster member dilution. For each uncertainty and systematic effect, we describe our mitigation scheme and the impact on cosmological parameter constraints. We obtain constraints on cosmological parameters from MCMC using CFIS data and MassiveNuS N-body simulations as a model for peak counts statistics. Depending on the calibration (local versus global, and the inclusion of the residual multiplicative shear bias), the mean matter density parameter $Ω_m$ can shift up to $-0.024$ ($-0.5σ$). We also see that including baryonic corrections can shift $Ω_m$ by $+0.027$ ($+0.5 σ$) with respect to the DM-only simulations. Reducing the impact of the intrinsic alignment and cluster member dilution through signal-to-noise cuts can lead to a shift in $Ω_m$ of $+0.027$ ($+0.5 σ$). Finally, with a mean redshift uncertainty of $Δ\bar{z} = 0.03$, we see that the shift of $Ω_m$ ($+0.001$ which corresponds to $+0.02 σ$) is not significant. This paper investigates for the first time with UNIONS weak-lensing data and peak counts the impact of systematic effects. The value of $Ω_m$ is the most impacted and can shift up to $\sim 0.03$ which corresponds to $0.5σ$ depending on the choices for each systematics. We expect constraints to become more reliable with future (larger) data catalogues, for which the current pipeline will provide a starting point.
description: 19 pages, 19 figures
Perturbational treatment of spin-orbit coupling for generally applicable high-level multi-reference methods
Creators: name: Mai, Sebastian
name: Müller, Thomas
name: Plasser, Felix
name: Marquetand, Philipp
name: Lischka, Hans
name: González, Leticia
Publisher: name: arXiv
Year: 2016
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: An efficient perturbational treatment of spin-orbit coupling within the framework of high-level multi-reference techniques has been implemented in the most recent version of the COLUMBUS quantum chemistry package, extending the existing fully variational two-component (2c) multi-reference configuration interaction singles and doubles (MRCISD) method. The proposed scheme follows related implementations of quasi-degenerate perturbation theory (QDPT) model space techniques. Our model space is built either from uncontracted, large-scale scalar relativistic MRCISD wavefunctions or based on the scalar-relativistic solutions of the linear-response-theory-based multi-configurational averaged quadratic coupled cluster method (LRT-MRAQCC). The latter approach allows for a consistent, approximatively size-consistent and size-extensive treatment of spin-orbit coupling. The approach is described in detail and compared to a number of related techniques. The inherent accuracy of the QDPT approach is validated by comparing cuts of the potential energy surfaces of acrolein and its S, Se, and Te analoga with the corresponding data obtained from matching fully variational spin-orbit MRCISD calculations. The conceptual availability of approximate analytic gradients with respect to geometrical displacements is an attractive feature of the 2c-QDPT-MRCISD and 2c-QDPT-LRT-MRAQCC methods for structure optimization and ab inito molecular dynamics simulations.
Tools and data requirements for assessing substances in foods: Development of the MCRA risk assessment tool and a consumer app
Creators: name: van Klaveren, Jacob
name: van der Voet, Hilko
Publisher: name: Zenodo
Year: 2021
Subjects: TDS
MCRA
consumer app
nickel
methylmercury
pesticides

description: Food may contain hazardous substances such as contaminants or residues from pesticides or food packaging materials. Food risk assessment requires many data (e.g. chemical concentrations, food consumption and health hazards). There are already well-established datasets (e.g. in EFSA collections), but also emerging datasets which can be very useful (e.g. data from total diet studies). Tools for food risk assessment are available, but require well-formatted input data. Data harmonisation and data conversion are therefore essential steps. Food risk assessment is complex and is constantly evolving, using more complex statistical approaches as the discipline develops. Therefore it is useful to develop demonstrator software to facilitate understanding and guide different identified user groups including risk assessors and consumers. Task 4.3 of the FNS-Cloud project aims to create e-services that enable two examples of user communities, consumers and researchers/risk assessors, to evaluate and visualise chemical food safety data. Consumers will be able to use concentration data from total diet studies (TDS) within decision making processes in their daily life, e.g. in the supermarket when purchasing foods. High-end users, e.g. risk assessors and researchers, will be able to use TDS or monitoring data for higher-tier more complex risk assessments. Specifically, the latter approach will use the probabilistic assessment with the Monte Carlo Risk Assessment (MCRA) tool. Within FNS-Cloud there are five phases in this process, split over WP 4 (Use cases) and WP 5 (Demonstrators), covering specification, implementation and testing (Task 4.3) and improvement and evaluation (in WP 5). In this report four use cases are outlined, using the MCRA tool (three use cases) or a new consumer app (one use case). The emphasis is on the formulation of user requirements, i.e. describing how the systems requirements should work for specific scenarios, on the required functionality of the tools, and on data organisation connecting different data sources such that they can be used together in the assessments. For some use cases preliminary results from running the exposure or risk assessments are reported. Final results of the use cases will be reported in a follow-up report (Deliverable 4.4).
Feeding, growth dynamics and behavior of the bioluminescent dinoflagellate, Polykrikos kofoidi
Creators: name: Schmidt, Richard Keith, 1969-
Publisher: name: The University of Texas at Austin
Year: 1993
Subjects: subject: Polykrikos kofoidi
subject: Dinoflagellates
subject: Food
subject: Growth
subject: Behavior
subject: Food behavior
subject: Dinoflagellates--Food
subject: Dinoflagellates--Growth
subject: Dinoflagellates--Behavior

description: The dinoflagellate Polykrikos kofoidi is a pseudocolonial, bioluminescent heterotrophic species which has been known to readily feed upon other nearshore dinoflagellate blooms, such as red tides. This heterotrophic dinoflagellate was found to feed preferentially on photosynthetic dinoflagellates with a diameter of 30 μm and greater, but at high food concentrations. For all food species tested, Gyrodinium dorsum, Gonyaulax polyedra and a 50/50 mixture (based on carbon content), growth rates reached maximal values at 4-6 mg C 1⁻¹ (μmax] = 0.8 d-1) . The feeding rate of P. kofoidi increased with food concentrations and did not appear to saturate at concentrations up to 8-10 mg C 1⁻¹, which was supported by encounter rates calculated for each food treatment. Encounters with food cells (cells/day) by each P. kofoidi were not significantly different (paired Student's t-test, α=0.05) from the number of cells ingested per day for each individual, which also indicates that P. kofoidi must contact a prey cell to feed and cannot locate prey using remote chemical cues in the water. A comparison of swimming behavior in the presence and absence of prey cells and prey exudate also supports the assumption of the inability of P. kofoidi to detect remote chemical cues in the water. The bioluminescent capacity of P. kofoidi exhibited a positive correlation with growth rate over varying food concentrations. The constant increase in ingestion of food, even in concentrations as high as 8-10 mg C 1⁻¹, coupled with a growth rate that exceeded that of its preferred food species, will allow P. kofoidi to exploit blooms of dinoflagellates and could serve as a biological control agent to help control red tides
VECSEL systems for generation and manipulation of trapped magnesium ions
Creators: name: Burd, Shaun C.
name: Allcock, David T. C.
name: Leinonen, Tomi
name: Penttinen, Jussi-Pekka
name: Slichter, Daniel H.
name: Srinivas, Raghavendra
name: Wilson, Andrew C.
name: Jördens, Robert
name: Guina, Mircea
name: Leibfried, Dietrich
name: Wineland, David J.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Experiments in atomic, molecular, and optical (AMO) physics rely on lasers at many different wavelengths and with varying requirements on spectral linewidth, power, and intensity stability. Vertical external-cavity surface-emitting lasers (VECSELs), when combined with nonlinear frequency conversion, can potentially replace many of the laser systems currently in use. Here we present and characterize VECSEL systems that can perform all laser-based tasks for quantum information processing experiments with trapped magnesium ions. For photoionization of neutral magnesium, 570.6$\,$nm light is generated with an intracavity frequency-doubled VECSEL containing a lithium triborate (LBO) crystal for second harmonic generation. External frequency doubling produces 285.3$\,$nm light for resonant interaction with the $^{1}S_{0}\leftrightarrow$ $^{1}P_{1}$ transition of neutral Mg. Using an externally frequency-quadrupled VECSEL, we implement Doppler cooling of $^{25}$Mg$^{+}$ on the 279.6$\,$nm $^{2}S_{1/2}\leftrightarrow$ $^{2}P_{3/2}$ cycling transition, repumping on the 280.4$\,$nm $^{2}S_{1/2}\leftrightarrow$ $^{2}P_{1/2}$ transition, coherent state manipulation, and resolved sideband cooling close to the motional ground state. Our systems serve as prototypes for applications in AMO requiring single-frequency, power-scalable laser sources at multiple wavelengths.
description: 6 pages, 9 figures
Spinsim: a GPU optimized python package for simulating spin-half and spin-one quantum systems
Creators: name: Tritt, Alex
name: Morris, Joshua
name: Hochstetter, Joel
name: Anderson, R. P.
name: Saunderson, James
name: Turner, L. D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: The Spinsim python package simulates spin-half and spin-one quantum mechanical systems following a time dependent Shroedinger equation. It makes use of numba.cuda, which is an LLVM (Low Level Virtual Machine) compiler for Nvidia Cuda compatible systems using GPU parallelization. Along with other optimizations, this allows for speed improvements from 3 to 4 orders of magnitude while staying just as accurate, compared to industry standard packages. It is available for installation on PyPI, and the source code is available on github. The initial use-case for the Spinsim will be to simulate quantum sensing-based ultracold atom experiments for the Monash University School of Physics \& Astronomy spinor Bose-Einstein condensate (spinor BEC) lab, but we anticipate it will be useful in simulating any range of spin-half or spin-one quantum systems with time dependent Hamiltonians that cannot be solved analytically. These appear in the fields of nuclear magnetic resonance (NMR), nuclear quadrupole resonance (NQR) and magnetic resonance imaging (MRI) experiments and quantum sensing, and with the spin-one systems of nitrogen vacancy centres (NVCs), ultracold atoms, and BECs.
description: 20 pages, 4 figures. Software metapaper for https://github.com/alexander-tritt-monash/spinsim
Induced fermionic charge and current densities in two-dimensional rings
Creators: name: Bellucci, S.
name: Saharian, A. A.
name: Grigoryan, A. Kh.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: For a massive quantum fermionic field, we investigate the vacuum expectation values (VEVs) of the charge and current densities induced by an external magnetic flux in a two-dimensional circular ring. Both the irreducible representations of the Clifford algebra are considered. On the ring edges the bag (infinite mass) boundary conditions are imposed for the field operator. This leads to the Casimir type effect on the vacuum characteristics. The radial current vanishes. The charge and the azimuthal current are decomposed into the boundary-free and boundary-induced contributions. Both these contributions are odd periodic functions of the magnetic flux with the period equal to the flux quantum. An important feature that distinguishes the VEVs of the charge and current densities from the VEV of the energy density, is their finiteness on the ring edges. The current density is equal to the charge density for the outer edge and has the opposite sign on the inner edge. The VEVs are peaked near the inner edge and, as functions of the field mass, exhibit quite different features for two inequivalent representations of the Clifford algebra. We show that, unlike the VEVs in the boundary-free geometry, the vacuum charge and the current in the ring are continuous functions of the magnetic flux and vanish for half-odd integer values of the flux in units of the flux quantum. Combining the results for two irreducible representations, we also investigate the induced charge and current in parity and time-reversal symmetric models. The corresponding results are applied to graphene rings with the electronic subsystem described in terms of the effective Dirac theory with the energy gap. If the energy gaps for two valleys of the graphene hexagonal lattice are the same, the charge densities corresponding to the separate valleys cancel each other, whereas the azimuthal current is doubled.
description: 29 pages, 9 figures, PACS numbers: 03.70.+k, 11.27.+d, 04.60.Kz
Cooperative Phoneotypes: Exploring Phone-based Behavioral Markers of Cooperation
Creators: name: Singh, Vivek K.
name: Agarwal, Rishav R.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Social and Information Networks (cs.SI)
subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences
subject: J.4

description: Cooperation is a fundamental human concept studied across multiple social and biological disciplines. Traditional methods for eliciting an individual's propensity to cooperate have included surveys and laboratory experiments and multiple such studies have connected an individual's cooperation level with her social behavior. We describe a novel approach to model an individual's cooperation level based on her phoneotype i.e. a composite of an individual's traits as observable via a mobile phone. This phone sensing-based method can potentially complement surveys, thus providing a cheaper, faster, automated method for generating insights into cooperation levels of users. Based on a 10-week field study involving 54 participants, we report that: (1) multiple phone-based signals were significantly associated with participant's cooperation attitudes; and (2) combining phone-based signals yielded a predictive model with AUCROC of 0.945 that performed significantly better than a comparable demography-based model at predicting individual cooperation propensities. The results pave the way for individuals and organizations to identify more cooperative peers in personal, social, and commerce related settings.
description: To appear in UbiComp'16
Bayesian Integrals on Toric Varieties
Creators: name: Borinsky, Michael
name: Sattelberger, Anna-Laura
name: Sturmfels, Bernd
name: Telen, Simon
Publisher: name: arXiv
Year: 2022
Subjects: subject: Algebraic Geometry (math.AG)
subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 14M25, 62F15 (primary), 65D30 (secondary)

description: We explore the positive geometry of statistical models in the setting of toric varieties. Our focus lies on models for discrete data that are parameterized in terms of Cox coordinates. We develop a geometric theory for computations in Bayesian statistics, such as evaluating marginal likelihood integrals and sampling from posterior distributions. These are based on a tropical sampling method for evaluating Feynman integrals in physics. We here extend that method from projective spaces to arbitrary toric varieties.
description: 26 pages, 3 figures; v2: minor corrections and improvements, version equivalent to the one published in SIAGA
On the Global Stability of a Beta-Plane Equation
Creators: name: Pusateri, Fabio
name: Widmayer, Klaus
Publisher: name: arXiv
Year: 2016
Subjects: subject: Analysis of PDEs (math.AP)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We study the motion of an incompressible, inviscid two-dimensional fluid in a rotating frame of reference. There the fluid experiences a Coriolis force, which we assume to be linearly dependent on one of the coordinates. This is a common approximation in geophysical fluid dynamics and is referred to as beta-plane. In vorticity formulation the model we consider is then given by the Euler equation with the addition of a linear anisotropic, non-degenerate, dispersive term. This allows us to treat the problem as a quasilinear dispersive equation whose linear solutions exhibit decay in time at a critical rate. Our main result is the global stability and decay to equilibrium of sufficiently small and localized solutions. Key aspects of the proof are the exploitation of a "double null form" that annihilates interactions between spatially coherent waves and a lemma for Fourier integral operators which allows us to control a strong weighted norm.
description: 35 pages
A Search for O_2 in CO-depleted Molecular Cloud Cores with Herschel
Creators: name: Wirström, Eva S.
name: Charnley, Steven B.
name: Cordiner, Martin A.
name: Ceccarelli, Cecilia
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The general lack of molecular oxygen in molecular clouds is an outstanding problem in astrochemistry. Extensive searches with SWAS, Odin and Herschel have only produced two detections; upper limits to the O_2 abundance in the remaining sources observed are about 1000 times lower than predicted by chemical models. Previous atomic oxygen observations and inferences from observations of other molecules indicated that high abundances of O atoms might be present in dense cores exhibiting large amounts of CO depletion. Theoretical arguments concerning the oxygen gas-grain interaction in cold dense cores suggested that, if O atoms could survive in the gas after most of the rest of the heavy molecular material has frozen out on to dust, then O_2 could be formed efficiently in the gas. Using Herschel HIFI we searched a small sample of four depletion cores - L1544, L694-2, L429, Oph D - for emission in the low excitation O_2 N_J=3_3-1_2 line at 487.249 GHz. Molecular oxygen was not detected and we derive upper limits to its abundance in the range N(O_2)/N(H_2) = (0.6 - 1.6)x10^{-7}. We discuss the absence of O_2 in the light of recent laboratory and observational studies.
description: Accepted for publication in ApJ
Soft behavior of a closed massless state in superstring and universality in the soft behavior of the dilaton
Creators: name: Di Vecchia, Paolo
name: Marotta, Raffaele
name: Mojaza, Matin
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the tree-level scattering amplitudes in the NS-NS (Neveu-Schwarz) massless sector of closed superstrings in the case where one external state becomes soft. We compute the amplitudes generically for any number of dimensions and any number and kind of the massless closed states through the subsubleading order in the soft expansion. We show that, when the soft state is a graviton or a dilaton, the full result can be expressed as a soft theorem factorizing the amplitude in a soft and a hard part. This behavior is similar to what has previously been observed in field theory and in the bosonic string. Differently from the bosonic string, the supersymmetric soft theorem for the graviton has no string corrections at subsubleading order. The dilaton soft theorem, on the other hand, is found to be universally free of string corrections in any string theory.
description: 27 pages, one appendix
Baryon number violation from confining New Physics
Creators: name: Arun, Mathew Thomas
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The detection of neutron-antineutron oscillation will be a discovery of fundamental importance in particle physics and cosmology. In models discussed widely in literature, the process is generated through heavy New Physics with weak, perturbative, coupling at the scale of the experiment. Acknowledging the fact that Nature has been quite evasive regarding the strength and scale of New Physics, we discuss a new mechanism, generated by confining New Physics, at $\sim 2$ GeV, resulting in low-energy baryon number violating effects. The mechanism predicts baryon number violating processes like neutron disappearance, neutron-neutron annihilation and neutron-anti neutron oscillation generated through the condensation of the linear moose.
description: 11 pages, 8 figures, accepted for publishing in Physical Review D
Testing for serial correlation in the disturbances of a simultaneous equation model
Creators: name: Edwards, Phillip Martin.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Type III seesaw with R-parity violation in light of $m_W$ (CDF)
Creators: name: Ghoshal, Anish
name: Okada, Nobuchika
name: Okada, Satomi
name: Raut, Digesh
name: Shafi, Qaisar
name: Thapa, Anil
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Motivated by the recently reported measurement of the $W$ boson mass $M_W = 80.4335 \pm 0.0094$ GeV by the CDF collaboration, we propose a type III seesaw extension of the minimal supersymmetric standard model (MSSM) which also includes an R-parity violating term. Without taking potential SUSY radiative corrections into account, we show that the CDF measurement of $M_W$ and the LEP measurement of the $ρ$ parameter can be simultaneously accommodated at the $2 σ$ level. A long-lived gravitino in a few GeV mass range is a unique viable dark matter candidate in this framework.
description: 3 pages, typos corrected, references added, matches with published version
Direct measurement of lensing amplification in Abell S1063 using a strongly lensed high redshift HII Galaxy
Creators: name: Terlevich, Roberto
name: Melnick, Jorge
name: Terlevich, Elena
name: Chavez, Ricardo
name: Telles, Eduardo
name: Bresolin, Fabio
name: Plionis, Manolis
name: Basilakos, Spyros
name: Arenas, David Fernandez
name: Moran, Ana Luisa Gonzalez
name: Diaz, Angeles I.
name: Aretxaga, Itziar
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: ID11 is an actively star forming extremely compact galaxy and Ly alpha emitter at z=3.117 that is gravitationally magnified by a factor of ~17 by the cluster of galaxies Hubble Frontier Fields AS1063. Its observed properties resemble those of low luminosity HII galaxies or Giant HII regions like 30-Doradus in the LMC. Using the tight correlation correlation between the Balmer-line luminosities and the width of the emission lines (typically L(Hbeta)-sigma(Hbeta)) valid for HII galaxies and Giant HII regions to estimate its total luminosity, we are able to measure the lensing amplification of ID11. We obtain an amplification of 23 +- 11 similar within errors to the value of ~17 estimated or predicted by the best lensing models of the massive cluster Abell S1063. We also compiled from the literature luminosities and velocity dispersions for a set of lensed compact starforming regions. There is more scatter in the L-sigma correlation for these lensed systems but on the whole the results tend to support the lensing models estimates of the magnification. Our result indicates that the amplification can be independently measured using the L-sigma relation in lensed Giant HII regions or HII galaxies. It also supports the suggestion, even if lensing model dependent, that the L-sigma relation is valid for low luminosity high-z objects. Ad-hoc observations of lensed starforming systems are required to accurately determine the lensing amplification.
description: Accepted for publication in A&A Letters on 8th July 2016. 5 pages, 1 figure
A systematic search for X-ray cavities in galaxy clusters, groups, and elliptical galaxies
Creators: name: Shin, Jaejin
name: Woo, Jong-Hak
name: Mulchaey, John S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We perform a comprehensive study of X-ray cavities using a large sample of X-ray targets selected from the Chandra archive. The sample is selected to cover a large dynamic range including galaxy clusters, groups, and individual galaxies. Using $β$-modeling and unsharp masking techniques, we investigate the presence of X-ray cavities for 133 targets that have sufficient X-ray photons for analysis. We detect 148 X-ray cavities from 69 targets and measure their properties, including cavity size, angle, and distance from the center of the diffuse X-ray gas. We confirm the strong correlation between cavity size and distance from the X-ray center similar to previous studies (i.e., Birzan et al. 2004; Diehl et al. 2008; Dong et al. 2010). We find that the detection rates of X-ray cavities are similar among galaxy clusters, groups and individual galaxies, suggesting that the formation mechanism of X-ray cavities is independent of environment.
description: 22 pages, 13 figures, Accepted to ApJS