cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Electronic structures and magnetic orders of Fe-vacancies ordered ternary iron selenides TlFe$_{1.5}$Se$_2$ and AFe$_{1.5}$Se$_2$ (A=K, Rb, or Cs)
Creators: name: Yan, Xun-Wang
name: Gao, Miao
name: LU, Zhong-Yi
name: Xiang, Tao
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: By the first-principles electronic structure calculations, we find that the ground state of the Fe-vacancies ordered TlFe$_{1.5}$Se$_2$ is a quasi-two-dimensional collinear antiferromagnetic semiconductor with an energy gap of 94 meV, in agreement with experimental measurements. This antiferromagnetic order is driven by the Se-bridged antiferromagnetic superexchange interactions between Fe moments. Similarly, we find that crystals AFe$_{1.5}$Se$_2$ (A=K, Rb, or Cs) are also antiferromagnetic semiconductors but with a zero-gap semiconducting state or semimetallic state nearly degenerated with the ground states. Thus rich physical properties and phase diagrams are expected.
description: Add results about AFe$_{1.5}$Se$_2$ (A=K, Rb, or Cs);4 pages and 7 figures
Towards Enabling Semantic Reasoning with Timely Dataflow and Differential Dataflow
Creators: name: Xhimi Hypi
Publisher: name: University of Illinois at Chicago
Year: 2020
Subjects: Uncategorized

description: In Big Data applications Data Volume, Data Variety and Data Velocity constitute three important challenges. In this thesis, we focus on the problem of Data Velocity and Data Variety. The Semantic Web offers solutions to Data Variety. Stream Processing, on the other hand, focuses on Data Velocity. Semantic Reasoning (SR) is the area that attempts to tackle the two problems at the same time. It aims at performing reasoning over Streaming Data from complex domain in a timely fashion. In this work, we aim at exploring a new approach in the SR area. We argue that problems in this area can be compared and ultimately solved as problems in Graph Stream Processing. So in this direction, we select two frameworks for efficient Graph Stream Processing: Timely Dataflow and Differential Dataflow and use them to perform SR tasks. After describing the main basic components needed for a better understanding of the topic, we formalize the problem. Based on this problem, we design the flow of the computation that will lead the implementation of the code. At the end, we show some performance values that will delineate a meaningful starting point on top of which we define further future work.
Spatially Resolved Dynamic Structure Factor of Finite Systems from MD Simulations
Creators: name: Raitza, Thomas
name: Reinholz, Heidi
name: Morozov, Igor
name: Röpke, Gerd
Publisher: name: arXiv
Year: 2011
Subjects: subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The dynamical response of metallic clusters up to $10^3$ atoms is investigated using the restricted molecular dynamics simulations scheme. Exemplarily, sodium like material is considered. Correlation functions are evaluated to investigate the spatial structure of collective electron excitations and optical response of laser excited clusters. In particular, the spectrum of bi-local correlation functions shows resonances representing different modes of collective excitations inside the nano plasma. The spatial structure, the resonance energy and width of the eigenmodes have been investigated for various values of electron density, temperature, cluster size and ionization degree. Comparison with bulk properties is performed and the dispersion relation of collective excitations is discussed.
Regulators of VC Motor Neuron Differentiation and Specification in C. elegans
Creators: name: Perez, Lillian
Publisher: name: University of Illinois at Chicago
Year: 2020
Subjects: Uncategorized

description: The ventral cord neurons in the nematode C. elegans belong to eight distinct classes and are generated during embryonic and postembryonic development. The ventral cord class C (VCs) make up six out of eight sex-specific motor neurons found in the hermaphrodite. The aim of this work was twofold: (1) to characterize VC differentiation with molecular markers (2) to examine whether a conserved proneural factor containing a basic helix loop helix domain, HLH-3, had a function in the development of these neurons and how. First, this work establishes that the gene encoding this factor, hlh-3 is expressed during all stages of VC development revealing a newly identified role in these neurons. Second, this work demonstrates that acquisition of VC specific differentiation markers is dynamic in space and time. Characterization in the hlh-3(tm1688) deletion (null) mutant background revealed that differentiation of the VCs requires hlh-3 function. These findings also show that cell autonomous expression of hlh-3 restores VC differentiation. However, because the role of hlh-3 was primarily in one VC subclass (distal), this left an opportunity to examine regulators of the other subclass (proximal). Next, this work hypothesized that an additional regulator of VC differentiation, could be another conserved bHLH encoding gene, hlh-10. Through the characterization of VC differentiation in the absence of hlh-10 function, a repressive role was identified: two VC specific genes were negatively regulated by hlh-10, but positively regulated by hlh-3. Therefore, these findings suggested that the VC class gene, lin-11, could be regulated by these distinct bHLH containing factors. Finally, this work examined one mechanism for the regulation of lin-11 expression in VCs. By analysis of a VC enhancer element, the expression of lin-11 was shown to be repressed in non-VCs.
Biological Assessment of Used Dental Implant Healing Abutments
Creators: name: Aniruddh Narvekar
Publisher: name: University of Illinois at Chicago
Year: 2020
Subjects: Uncategorized

description: Objective: To determine if healing abutments (HA) can be truly “decontaminated” and to evaluate 4 decontamination strategies, available in most clinical settings, to determine the extent to which biomaterial can be removed compared to new unused HA. Methods: Forty HA were collected from subjects with prior implant placement were randomly distributed and detoxified using four protocols (A-D, N=10/group). Residual protein quantification (N=3/group) and macroscopic debris evaluation (N=2/group) was assessed. Human primary monocyte-derived macrophages (Mφ) were challenged with HA (N=5/group) and supernatants were collected at 4, 24, 48 and 120 h to analyze secretion of cytokines/chemokines. Results: Our study showed test groups (A-D) were not able to be “decontaminated” to levels of new, unused HA. A multiplex analyte assay performed on “decontaminated” test groups (A-D) revealed high levels of cytokine and chemokine secretion. HA should not be re-used due to the potential to initiate an inflammatory response, even after “decontamination” procedures are utilized.
Smart Process-Aware Tolerance Design and Quality Assurance for Additive and Hybrid Manufacturing
Creators: name: Azadeh Haghighi
Publisher: name: University of Illinois at Chicago
Year: 2020
Subjects: Uncategorized

description: The emergence of Additive Manufacturing (AM) has paved the way for fabrication of highly complex geometries and internal structures, owing to its unique layer-wise manufacturing approach. The AM technology also holds great potential for improving material efficiency and reducing life cycle environmental impacts and carbon footprint, which helps with promoting a sustainable “green” manufacturing strategy. Recently, the AM trend has shifted from fabrication of prototypes to functional end-use metallic or polymeric products in various critical industries including aerospace, automotive and healthcare. Consequently, ensuring the final quality of these single-component or multi-component products has become more important than ever. As a result, prediction, control, and enhancing the dimensional, geometric and mechanical properties of additively manufactured products have attracted significant research interest. A promising approach to overcome the limitations of AM in terms of quality is the adoption of hybrid additive-subtractive manufacturing processes. Nonetheless, this approach introduces new challenges for quality assurance and sustainable production planning, as multiple processes with different characteristics are involved. In this dissertation, a set of analytical models and decision-making tools are established, both at the process and product levels, to help designers and manufacturers with quality assurance and tolerance design of single- and multi-component products fabricated by additive and hybrid additive-subtractive manufacturing processes. Some of the discussed topics include surface roughness and porosity characterization, process-aware tolerancing, and application of data-driven and artificial intelligence techniques – towards smarter manufacturing. Furthermore, the development procedure and capabilities of a robotic hybrid additive-subtractive manufacturing platform are presented and discussed. The outcomes of this research will contribute towards the innovation of smart additive and hybrid manufacturing design software, machines, and equipment.
The Physics of Protoplanetesimal Dust Agglomerates. Vi. Erosion of Large Aggregates as a Source of Micrometer-Sized Particles
Creators: name: Schräpler, Rainer
name: Blum, Jürgen
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Observed protoplanetary disks consist of a large amount of micrometer-sized particles. Dullemond and Dominik (2005) pointed out for the first time the difficulty in explaining the strong mid-IR excess of classical T-Tauri stars without any dust-retention mechanisms. Because high relative velocities in between micrometer-sized and macroscopic particles exist in protoplanetary disks, we present experimental results on the erosion of macroscopic agglomerates consisting of micrometer-sized spherical particles via the impact of micrometer-sized particles. We find that after an initial phase, in which an impacting particle erodes up to 10 particles of an agglomerate, the impacting particles compress the agglomerate's surface, which partly passivates the agglomerates against erosion. Due to this effect the erosion halts within our error bars for impact velocities up to ~30 m/s. For larger velocities, the erosion is reduced by an order of magnitude. This outcome is explained and confirmed by a numerical model. In a next step we build an analytical disk model and implement the experimentally found erosive effect. The model shows that erosion is a strong source of micrometer-sized particles in a protoplanetary disk. Finally we use the stationary solution of this model to explain the amount of micrometer-sized particles in observational infrared data of Furlan et al. (2006).
Blowup for the C^1 Solutions of the Euler-Poisson Equations of Gaseous Stars in R^N
Creators: name: Yuen, Manwai
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mathematical Physics (math-ph)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Analysis of PDEs (math.AP)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 35B30, 35B44, 35Q35, 35Q85, 85A05

description: The Newtonian Euler-Poisson equations with attractive forces are the classical models for the evolution of gaseous stars and galaxies in astrophysics. In this paper, we use the integration method to study the blowup problem of the $N$-dimensional system with adiabatic exponent $γ>1$, in radial symmetry. We could show that the $C^{1}$ non-trivial classical solutions $(ρ,V)$, with compact support in $[0,R]$, where $R>0$ is a positive constant with $ρ(t,r)=0$ and $V(t,r)=0$ for $r\geq R$, under the initial condition \begin{equation} H_{0}=\int_{0}^{R}r^{n}V_{0}dr>\sqrt{\frac{2R^{2n-N+4}M}{n(n+1)(n-N+2)}}% \end{equation} with an arbitrary constant $n>\max(N-2,0),$\newline blow up before a finite time $T$ for pressureless fluids or $γ>1.$ Our results could fill some gaps about the blowup phenomena to the classical $C^{1}$ solutions of that attractive system with pressure under the first boundary condition.\newline In addition, the corresponding result for the repulsive systems is also provided. Here our result fully covers the previous case for $n=1$ in "M.W. Yuen, \textit{Blowup for the Euler and Euler-Poisson Equations with Repulsive Forces}, Nonlinear Analysis Series A: Theory, Methods & Applications 74 (2011), 1465--1470".
description: 12 pages, We merged the result in "M.W. Yuen, Blowup for the Euler and Euler-Poisson Equations with Repulsive Forces II, Pre-print, arXiv:1012.5143" in the updated version. Key Words: Euler-Poisson Equations, Integration Method, Blowup, Repulsive Forces, With Pressure, $C^{1}$ Solutions, No-Slip Boundary Condition, Compact Support, Initial Value Problem, First Boundary Condition
Feedback Regulated Star Formation: Implications for the Kennicutt-Schmidt Law
Creators: name: Dib, Sami
Publisher: name: arXiv
Year: 2011
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We derive a metallicity dependent relation between the surface density of the star formation rate (Sigma_{SFR}) and the gas surface density (Sigma_{g}) in a feedback regulated model of star formation in galactic disks. In this model, star formation occurs in gravitationally bound protocluster clumps embedded in larger giant molecular clouds with the protocluster clump mass function following a power law function with a slope of -2. Metallicity dependent feedback is generated by the winds of OB stars (M > 5 Msol) that form in the clumps. The quenching of star formation in clumps of decreasing metallicity occurs at later epochs due to weaker wind luminosities, thus resulting in higher final star formation efficiencies (SFE_{exp}). By combining SFE_{exp} with the timescales on which gas expulsion occurs, we derive the metallicity dependent star formation rate per unit time in this model as a function of Sigma_{g}. This is combined with the molecular gas fraction in order to derive the global dependence of Sigma_{SFR} on Sigma_{g}. The model reproduces very well the observed star formation laws extending from low gas surface densities up to the starburst regime. Furthermore, our results show a dependence of $Σ_{SFR}$ on metallicity over the entire range of gas surface densities in contrast to other models, and can also explain part of the scatter in the observations. We provide a tabulated form of the star formation laws that can be easily incorporated into numerical simulations or semi-analytical models of galaxy formation and evolution.
description: accepted to ApJL. Slopes of the KS relations in different gas surface density regimes are now quoted in the text. Figures and conclusions unchanged
School literacy as a catalyst : a portrait from multilingual, low-educated homes in Turkey
Creators: name: Koçbaş Demir, Bünser Dilara
Publisher: name: University of British Columbia
Year: 2016

description: This study examines the catalyzing effect of school literacies to initiate changes in the two multilingual and un- or under-schooled families at a period of time when the focal children started school in Turkey. My research draws particularly upon four interrelated theoretical perspectives. First, the sociocultural-historical theory emphasizes the social, cultural, and historical basis of social interaction and literacy activities (Rogoff, 2003; Vygotsky, 1978). The ecological theory promotes the idea that literacy and literacy activities are determined by overlapping social and cultural niches (Bronfenbrenner, 1979; 2000; 2005). Finally, I focus on the applications of critical approaches to literacy studies, such as critical pedagogy theory (Freire & Macedo, 1987) and the sociocritical literacy framework (Gutiérrez, 2005; 2008; Gutiérrez, Rymes & Larson, 1995) to argue for links between social power and literacy and literacy activities. As for the methodological approach, this study can be defined as a case study using ethnographic techniques (Dyson & Genishi, 2005). The data were collected through semi-structured interviews and participatory observations both in the homes and in the school. Data analysis includes discourse analysis to identify salient themes about how language is used to perform social identities and social activities (Gee, 2005; Marshall & Rossman, 2011). The findings point out that, first, the religious literacy skills in one focal family were recontextualized to make some connections with school, which was not a familiar domain for the family. Second, I provide evidence for the ways in which school-based abilities determined the categories of identity as forms of favorable and unfavorable self-definition for the focal participants, providing the focal children with a space to challenge the authority of their parents. This qualitative study is an attempt to understand how focal participants took positions, and negotiated their identities with one another based on their abilities to read and write. My study will shed light on the educational experiences of children, together with their families, who are marginalized as a result of having little or no formal education and speaking minority languages.
Convex Integration and the Navier-Stokes Equations
Creators: name: Xiaoyutao Luo
Publisher: name: University of Illinois at Chicago
Year: 2020
Subjects: Uncategorized

description: This work is devoted to applying the convex integration technique that has been recently developed in fluid dynamics to the incompressible Navier-Stoke equations in dimensions $d \geq 3$. The main results include the existence of stationary weak solutions in dimensions $d \geq 4$ proved in Chapter 2 and in $3D$ which is proved in Chapter 3 where we also construct weak solutions in $3D$ whose energy profiles are discontinuous on some dense sets of positive Lebesgue measure in time.
$\mathcal{PT}$ breaking and RG flows between multicritical Yang-Lee fixed points
Creators: name: Lencsés, Máté
name: Miscioscia, Alessio
name: Mussardo, Giuseppe
name: Takács, Gábor
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2023
Subjects: parity, time reversal
renormalization group, flow
model, minimal
dimension, 2
PT symmetry
singularity
critical phenomena
spontaneous symmetry breaking
fixed point
conformal

description: We study a novel class of Renormalization Group flows which connect multicritical versions of the two-dimensional Yang-Lee edge singularity described by the conformal minimal models $\mathcal{M}$(2,2n+3). The absence in these models of an order parameter implies that the flows towards and between Lee-Yang edge singularities are all related to the spontaneous breaking of $\mathcal{PT}$ symmetry and comprise a pattern of flows in the space of $\mathcal{PT}$ symmetric theories consistent with the c-theorem and the counting of relevant directions. Additionally, we find that while in a part of the phase diagram the domains of unbroken and broken $\mathcal{PT}$ symmetry are separated by critical manifolds of class $\mathcal{M}$(2,2n+3), other parts of the boundary between the two domains are not critical.
On the elliptical flow and asymmetry of the colliding nuclei
Creators: name: Kaur, Varinderjit
name: Kumar, Suneel
name: Puri, Rajeev K.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A study of elliptical flow is presented with respect to the asymmetry of colliding nuclei using the reactions of 24Cr50 +44 Ru102, 16S32 +50 Sn120 and 8O16 +54 Xe136 at incident energies between 50 and 250 MeV/nucleon within the framework of isospin-dependent quantum molecular dynamics model. For the present analysis, total mass of the colliding pairs is kept fixed and asymmetry is varied as ? = 0.2, 0.3, 0.7. The elliptical flow shows a transition from in-plane to out-of-plane in the mid rapidity region with incident energy. The transition energy is found to increase with the asymmetry for lighter fragments.
Validation and optimization of myelin water imaging in a preclinical model of spinal cord injury
Creators: name: Chen, Henry Szu-Meng
Publisher: name: University of British Columbia
Year: 2017

description: Myelin content is an important marker for neuropathology; however, direct imaging of myelin is difficult. Consequently, quantitative T2 based myelin water imaging measures myelin content indirectly by probing the property of the surrounding water. Typically, a lengthy multi-echo spin-echo sequence is used to obtain decay curves that are fitted to produce T2 distributions. In white matter, two peaks are observed, one with short and one with long T2 associated with water trapped between the myelin lipid bilayers and intra/extracellular water. The ratio of myelin water peak to the entire distribution is called the myelin water fraction (MWF) and correlates well the myelin content. This thesis has two parts. The first half deals with the use of compressed sensing (CS) to accelerate the lengthy sequence used in myelin water imaging. The CS CPMG sequence was implemented in 2D utilizing group-sparse reconstruction in order to take advantage of the correlation between echoes. Simulated undersampling and real undersampling experiments were performed. It was found that acceleration up to 2× was possible without impacting MWF map quality, wherever adequate SNR was available. This is followed by a brief investigation into 3D CS CPMG, where similar results were achieved. The second part of the thesis focuses on myelin water imaging in the presence of myelin debris. Because MWF is associated with the water trapped in between the myelin lipid bilayers, the reading depends heavily on myelin morphology. I compared MWF to transmission electron microscopy (TEM) derived myelin fraction using a rat injury model at normal (normal myelin), 3 weeks post-injury (a large amount of myelin debris), and 8 weeks post-injury (myelin debris partially cleared). I found that myelin water fraction correlated strongly with the amount of myelin lipid bilayers in both intact myelin and myelin debris. From the TEM images, it appears that myelin debris consists of areas of either normally spaced myelin or large watery spaces. No significant difference was found in myelin period among the three groups.
Study of Jet Quenching in Quark Gluon Plasma Using Jet Charge Measurements
Creators: name: Dhanush Anil Hangal
Publisher: name: University of Illinois at Chicago
Year: 2020
Subjects: Uncategorized

description: The properties of quark-gluon plasma (QGP) are studied using jets, which are collimated streams of hadrons produced by fragmentation of high transverse momentum quarks and gluons from hard scatterings in the early phase of heavy-ion collisions. These hard-scattered quarks and gluons subsequently traverse and interact with the QGP, losing energy. This phenomenon is referred to as jet quenching. The jets are thus used as in-situ probes to analyze the rich dynamics of the QGP medium. Recent calculations from models operating at different energy scales predict varying magnitudes of color-charge dependence for the jet-medium interactions. In this work, the properties of the QGP are further explored using jet charge measurements in 5.02 TeV PbPb collisions recorded with the CMS detector along with pp data at the same energy. Jet charge is defined as the momentum-weighted sum of electric charges of particles inside a jet. The sensitivity of the jet charge to the electric charge of the initiating parton can be leveraged to discriminate between quark- and gluon-jets. A template-fitting method is presented to extract the quark- and gluon-jet fractions in pp and PbPb collisions using jet charge templates from simulations. The first jet charge measurement in heavy-ion collisions is carried out in this work and can provide further constraints to theoretical models describing the QGP, including the color charge dependence of jet quenching.
D=4, N=2 Gauged Supergravity coupled to Vector-Tensor Multiplets
Creators: name: Andrianopoli, Laura
name: D'Auria, Riccardo
name: Sommovigo, Luca
name: Trigiante, Mario
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct the general four-dimensional N=2 supergravity theory coupled to vector and vector-tensor multiplets only. Consistency of the construction requires the introduction of the vector fields dual to those sitting in the same supermultiplets as the antisymmetric tensors, as well as the scalar fields dual to the tensors themselves. Gauge symmetries also involving these additional fields guarantee the correct counting of the physical degrees of freedom.
description: Typos corrected, references added
title: Acute sacroiliitis complicated with pelvic muscle abscesses: A pediatric case report
Creators: name: Bay, Büşra
Publisher: name: EURORAD
Year: 2022
Subjects: subject: Musculoskeletal system
subject: Musculoskeletal joint
subject: MR
subject: Musculoskeletal joint
subject: Clinical Cases

description: Clinical History: A 17-year-old female, previously healthy, was admitted with symptoms of sudden hip pain and fever. 

Blood count showed microcytic anaemia, and increased leukocytes. C-reactive protein and erythrocyte sedimentation rates were elevated. Blood and throat cultures, covid PCR tests were negative. 

A diagnostic work-up for possible arthropathies and other chronic infectious diseases were done and all resulted unremarkable. Tuberculosis spot test and QuantiFERON tests were negative. Brucella serologic tests were negative.

description: 17 years, female
3D Analysis of Variation in Alveolar Cleft Defect Shape and Size
Creators: name: Bakhsh, Nora M
Publisher: name: University of Illinois at Chicago
Year: 2020
Subjects: Uncategorized

description: Objective: With the advent of precision medicine and advances in biopriting a more exact understanding of cleft defect variability is required. This study examines patterns of shape/size variation of alveolar cleft defects. Materials: 32 CBCT scans of patients (age 5-35) were used to model the shape of cleft defects. 3D Slicer was used to create models of the negative space, the sizes and volumes of which were measured using Geomagic; shape was analyzed using geometric morphometric methods and a cluster analysis. Results: We have identified a 2-cluster pattern of common shape variation which differentiate between clefts that are wider (medio-laterally) and those that are taller (supero-inferiorly). A Significant difference was found between unilateral and bilateral clefts in height and volume. A high variability in size and volume was also observed. Conclusions: There is a great degree of variation in cleft size and volume, which will likely impact the survivability of cells in bioprinted scaffolds, along with affecting the biomechanical strain across the cleft defect.
On the new translational shape invariant potentials
Creators: name: Ramos, Arturo
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 81Q05, 81Q60

description: Recently, several authors have found new translational shape invariant potentials not present in classic classifications like that of Infeld and Hull. For example, Quesne on the one hand and Bougie, Gangopadhyaya and Mallow on the other have provided examples of them, consisting on deformations of the classical ones. We analyze the basic properties of the new examples and observe a compatibility equation which has to be satisfied by them. We study particular cases of such equation and give more examples of new translational shape invariant potentials.
description: 9 pages, uses iopart10.clo, version 2
T-Duality For String in Horava-Lifshitz Gravity
Creators: name: Kluson, J.
name: Panigrahi, K. L.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We continue our study of the Lorentz breaking string theories. These theories are defined as string theory with modified Hamiltonian constraint which breaks the Lorentz symmetry of target space-time. We analyze properties of this theory in the target space-time that possesses isometry along one direction. We also derive the T-duality rules for Lorentz breaking string theories and show that they are the same as that of Buscher's T-duality for the relativistic strings.
description: 17 pages, references added
A tight binding model for water
Creators: name: Paxton, A. T.
name: Kohanoff, J. J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We demonstrate for the first time a tight binding model for water incorporating polarizable anions. A novel aspect is that we adopt a "ground up" approach in that properties of the monomer and dimer only are fitted. Subsequently we make predictions of the structure and properties of hexamer clusters, ice-XI and liquid water. A particular feature, missing in current tight binding and semiempirical hamiltonians, is that we reproduce the almost two-fold increase in molecular dipole moment as clusters are built up towards the limit of bulk liquid. We concentrate on properties of liquid water which are very well rendered in comparison with experiment and published density functional calculations. Finally we comment on the question of the contrasting densities of water and ice which is central to an understanding of the subtleties of the hydrogen bond.
Chiral Magnetic Wave
Creators: name: Kharzeev, Dmitri E.
name: Yee, Ho-Ung
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We consider a relativistic plasma containing charged chiral fermions in an external magnetic field, e.g a chirally symmetric quark-gluon plasma created in relativistic heavy ion collisions. We show that triangle anomalies imply the existence of a new type of collective gapless excitation in this system that stems from the coupling between the density waves of the electric and chiral charges; we call it "the Chiral Magnetic Wave" (CMW). The CMW exists even in a neutral plasma, i.e. in the absence of the axial and vector chemical potentials. We demonstrate the existence of CMW and study its properties using three different approaches: i) relativistic magnetohydrodynamics; ii) dimensional reduction to $(1+1)$ Sine-Gordon model, appropriate in a strong magnetic field; and iii) holographic QCD (Sakai-Sugimoto model), appropriate at strong coupling. We also briefly discuss the phenomenological implications of the CMW for heavy ion collisions.
description: 33 pages, 4 figures; v2: added two references
On Asymptotic Flatness and Lorentz Charges
Creators: name: Compère, Geoffrey
name: Dehouck, François
name: Virmani, Amitabh
Publisher: name: arXiv
Year: 2011
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper we establish two results concerning four-dimensional asymptotically flat spacetimes at spatial infinity. First, we show that the six conserved Lorentz charges are encoded in two unique, distinct, but mutually dual symmetric divergence free tensors that we construct from the equations of motion. Second, we show that integrability of Einstein's equations in the asymptotic expansion is sufficient to establish the equivalence between counter-term charges defined from the variational principle and charges defined by Ashtekar and Hansen. These results clarify earlier constructions of conserved charges in the hyperboloid representation of spatial infinity. In showing this, parity condition on the mass aspect is not needed. Along the way in establishing these results, we prove two lemmae on tensor fields on three dimensional de Sitter spacetime stated by Ashtekar-Hansen and Beig-Schmidt and state and prove three additional lemmae.
description: 26 pages; no figures; v2: minor changes; v3: clarifications + references + a new lemma added, results unaffected
Revisiting No-Scale Supergravity Inspired Scenarios: Updated Theoretical and Phenomenological Constraints
Creators: name: Benhenni, Amine
name: Kneur, Jean-Loic
name: Moultaka, Gilbert
name: Bailly, Sean
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider no-scale inspired supergravity scenarios, where the gravitino mass and related soft supersymmetry-breaking parameters are determined dynamically by radiative corrections to an essentially flat tree-level potential in the supersymmetry breaking hidden sector. We examine the theoretical and phenomenological viability of such a mechanism, when including up-to-date calculations of the low energy sparticle spectrum and taking into account the latest LHC results and other experimental constraints. We (re)emphasize the role of the scale-dependent vacuum energy contribution to the effective potential, in obtaining realistic no-scale electroweak minima, examining carefully the impact of boundary conditions and of variants of the minimization procedure. We also discuss and implement the B_0 (soft breaking Higgs mixing parameter) input boundary condition at high scale, therefore fixing tan beta(B_0) at low scales. For general high scale boundary conditions with non-vanishing B_0, m_0..., our analysis provides theoretical correlations among the supersymmetric, soft and vacuum energy parameters and related phenomenological consequences at the LHC. For instance, a zero vacuum energy at the GUT scale would lead to a decoupled supersymmetric spectrum, together with a light standard model-like Higgs boson at the electroweak scale. Given the experimental exclusion limits, a substantial class of the boundary conditions, and in particular the strict no-scale with m_0=A_0=B_0=0, are only compatible with a stau being the lightest MSSM particle. Then an enlarged allowed parameter space emerges when assuming a gravitino LSP to account for the observed dark matter relic density.
description: 37 pages, 13 figures, 2 tables. v2: some references added
Understanding the intercultural approach
Creators: name: Premat, Christophe
Publisher: name: Stockholm University
Year: 2022
Subjects: subject: 200209 Multicultural, Intercultural and Cross-cultural Studies
subject: FOS: Other humanities
subject: 200204 Cultural Theory
subject: 160104 Social and Cultural Anthropology
subject: FOS: Sociology

description: This introductory course was given at Stockholm University for students in French at the bachelor level. The course is about "intercultural relations and communicative competence" with an overview of theories borrowed from the Frankfurt school (critical theory), the school of Birmingham (18964-1980) and the French Theory. It explains the difference between the analysis of intercultural relations and cultural theories.
YORP torques with 1D thermal model
Creators: name: Breiter, Slawomir
name: Bartczak, Przemyslaw
name: Czekaj, Maria
Publisher: name: arXiv
Year: 2010
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: A numerical model of the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect for objects defined in terms of a triangular mesh is described. The algorithm requires that each surface triangle can be handled independently, which implies the use of a 1D thermal model. Insolation of each triangle is determined by an optimized ray-triangle intersection search. Surface temperature is modeled with a spectral approach; imposing a quasi-periodic solution we replace heat conduction equation by the Helmholtz equation. Nonlinear boundary conditions are handled by an iterative, FFT based solver. The results resolve the question of the YORP effect in rotation rate independence on conductivity within the nonlinear 1D thermal model regardless of the accuracy issues and homogeneity assumptions. A seasonal YORP effect in attitude is revealed for objects moving on elliptic orbits when a nonlinear thermal model is used.
description: 15 pages, 10 figures, accepted to MNRAS, before language editing
High-Intensity and High-Brightness Source of Moderated Positrons Using a Brilliant gamma Beam
Creators: name: Hugenschmidt, C.
name: Schreckenbach, K.
name: Habs, D.
name: Thirolf, P. G.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: Presently large efforts are conducted towards the development of highly brilliant gamma beams via Compton back scattering of photons from a high-brilliance electron beam, either on the basis of a normal-conducting electron linac or a (superconducting) Energy Recovery Linac (ERL). Particularly ERL's provide an extremely brilliant electron beam, thus enabling to generate highest-quality gamma beams. A 2.5 MeV gamma beam with an envisaged intensity of 10^15 s^-1, as ultimately envisaged for an ERL-based gamma-beam facility, narrow band width (10^-3), and extremely low emittance (10^-4 mm^2 mrad^2) offers the possibility to produce a high-intensity bright polarized positron beam. Pair production in a face-on irradiated W converter foil (200 micron thick, 10 mm long) would lead to the emission of 2 x 10^13 (fast) positrons per second, which is four orders of magnitude higher compared to strong radioactive ^22Na sources conventionally used in the laboratory.Using a stack of converter foils and subsequent positron moderation, a high-intensity low-energy beam of moderated positrons can be produced. Two different source setups are presented: a high-brightness positron beam with a diameter as low as 0.2 mm, and a high-intensity beam of 3 x 10^11 moderated positrons per second. Hence, profiting from an improved moderation efficiency, the envisaged positron intensity would exceed that of present high-intensity positron sources by a factor of 100.
description: 9 pages, 3 figures
A novel approach to estimate active carbon flux using the micronekton biomass spectra
Creators: name: Kwong, Lian Elizabeth
Publisher: name: University of British Columbia
Year: 2017

description: Micronekton play a critical role in global carbon cycling, actively transporting carbon between the surface and deep ocean during diel migrations. Carbon transport is mediated through respiration, gut flux, excretion and mortality of migrating organisms. Because marine ecological processes are strongly size dependent, it was proposed that active carbon transport can be measured from biomass spectra. The micronekton community was sampled during the Micronekton Intercalibration Experiment (MIE-1) in October of 2004 off the south west coast of Oahu. Sampling was conducted during both day and night in the epipelagic (0 – 120 m) and mesopelagic (550 – 650 m) layers, using three micronekton sampling gears (Cobb trawl, Isaacs-Kidd Midwater trawl, Hokkaido University Frame Trawl) and an acoustic echosounder (hull-mounted, dual-frequency, split-beam Simrad EK60). Micronekton species composition and size spectra varied depending on the depth and time of day. We estimated total migratory micronekton abundance and biomass to be ~487 ind.m-² and ~6,014 mgC m-², respectively, assuming that ~16% of micronekton remained within the epipelagic zone during the day. A biomass/production size dependent model based on the biomass spectra theory was developed to predict active carbon transport of micronekton. The model was robust against changes in respiration, excretion and mortality, but relatively sensitive to changes in the gut flux. The model estimated that vertically migrating micronekton exported approximately 88.5 mgC m-² day -¹ to ~450 m depth in this region. This estimate was substantially higher than the majority of past estimates, and comparable to recent total global carbon export estimates. The model output suggests that micronekton play a key role in active carbon cycling, and that their contribution to carbon cycling may have been underestimated. Therefore, behavioural and physiological responses of these organisms to changes in oceanic conditions may affect the efficiency and strength of the biological pump potentially reducing atmospheric CO₂ sink to the deep-ocean.
Phantom Inflation with A Steplike Potential
Creators: name: Liu, Zhi-Guo
name: Zhang, Jun
name: Piao, Yun-Song
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The phantom inflation predicts a slightly blue spectrum of tensor perturbation, which might be tested in coming observations. In normal inflation models, the introduction of step in its potential generally results in an oscillation in the primordial power spectrum of curvature perturbation. We will check whether there is a similar case in the phantom inflation with steplike potential. We find that for same potentials, the oscillation of the spectrum of phantom inflation is nearly same with that of normal inflation, the difference between them is the tilt of power spectrum.
description: 6 pages, 6 figures, minimal changed, to be published in PLB
Nonzero theta(13) for neutrino mixing in the context of A(4) symmetry
Creators: name: Ma, Ernest
name: Wegman, Daniel
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In the original 2004 paper which first derived tribimaximal mixing in the context of A(4), i.e. the non-Abelian finite symmetry group of the tetrahedron (Plato's fire), as its simplest application, it was also pointed out how theta(13) nonzero may be accommodated. On the strength of the new T2K result that 0.03 (0.04) < sin^2 2 theta(13) < 0.28 (0.34) for delta(CP)=0 and normal (inverted) neutrino mass hierarchy, we perform a more detailed analysis of how this original idea may be realized in the context of A(4).
description: 11 pages, 4 figures, version to appear in PRL
Superflow as a tool for studying superfluid 3He
Creators: name: Jennings, Ash
Publisher: name: Lancaster University
Year: 2022
Subjects: Low temperature
Condensed matter
Superfluid He

description: In this thesis, we use mechanical oscillators to induce fluid flow in the superfluid 3He in order to investigate the properties of several superfluid phases. In particular, we investigate the B phase below temperatures of 230 μK and superfluid 3He confined in an anisotropic aerogel. Superfluid 3He is a fermionic superfluid consisting of Cooper pairs. If the superfluid flows above a critical velocity called the Landau velocity, the Cooper pairs break and form into quasiparticles. When an oscillating object goes faster than the critical velocity, it experiences a large increase in the drag force on the object. In this work, we move a device in superfluid 3He-B with constant velocity rather than oscillating it. We see only a small increase in damping for velocities above the critical velocity, instead of the large increase. After subtracting the results of thermally excited quasiparticles, we demonstrate that the small increase in damping is due to expelling quasiparticles occupying surface-bound-states on the wire surface. By monitoring the thermometer response to the movements, we measure the Kapitza resistance. We also observe the damping of wires oscillating in superfluid 3He-B with a diameter approaching the coherence length. The damping is much smaller than expected from considering the collisions of thermally excited quasiparticles. Lastly, we built a new device for exploring the superfluid phases of 3He confined inside an anisotropic aerogel. The aerogel has 10 nm strands aligned parallel with a mean distance between the strands of 100 nm, close to the coherence length of the superfluid. The device can be moved and oscillated, inducing flow. By observing the resonance frequency and the damping of the device, one can measure the superfluid fraction and observe other phenomena in the superfluid. Sharp changes in the velocity of measurements below the aerogel transition temperature have been found using this technique.
All Maximally Entangled Four Qubits States
Creators: name: Gour, Gilad
name: Wallach, Nolan R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We find an operational interpretation for the 4-tangle as a type of residual entanglement, somewhat similar to the interpretation of the 3-tangle. Using this remarkable interpretation, we are able to find the class of maximally entangled four-qubits states which is characterized by four real parameters. The states in the class are maximally entangled in the sense that their average bipartite entanglement with respect to all possible bi-partite cuts is maximal. We show that while all the states in the class maximize the average tangle, there are only few states in the class that maximize the average Tsillas or Renyi $α$-entropy of entanglement. Quite remarkably, we find that up to local unitaries, there exists two unique states, one maximizing the average $α$-Tsallis entropy of entanglement for all $α\geq 2$, while the other maximizing it for all $0
description: 15 pages, 2 figures, Revised Version: many references added, an appendix added with a statement of the Kempf-Ness theorem
Pions are neither perturbative nor nonperturbative: Wilsonian renormalization group analysis of nuclear effective field theory including pions
Creators: name: Harada, Koji
name: Kubo, Hirofumi
name: Yamamoto, Yuki
Publisher: name: arXiv
Year: 2010
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Pionful nuclear effective field theory (NEFT) in the two-nucleon sector is examined from the Wilsonian renormalization group point of view. The pion exchange is cut off at the floating cutoff scale, $Λ$, with the short-distance part being represented as contact interactions in accordance with the general principle of renormalization. We derive the nonperturbative renormalization group equations in the leading order of the nonrelativistic approximation in the operator space including up to $\mathcal{O}(p^2)$ and find the nontrivial fixed points in the $^1S_0$ and $^3S_1$--$^3D_1$ channels which are identified with those in the pionless NEFT. The scaling dimensions, which determine the power counting, of the contact interactions at the nontrivial fixed points are also identified with those in the pionless NEFT. We emphasize the importance of the separation of the pion exchange into the short-distance and the long-distance parts, since a part of the former is nonperturbative while the latter is perturbative.
description: minor changes, title changed