cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Baryonic Phase in Holographic Descriptions of the QCD Phase Diagram
Creators: name: Evans, Nick
name: Kim, Keun-Young
name: Magou, Maria
name: Seo, Yunseok
name: Sin, Sang-Jin
Publisher: name: arXiv
Year: 2012
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 study holographic models of the QCD temperature-chemical potential phase diagram based on the D3/D7 system with chiral symmetry breaking. The baryonic phase may be included through linked D5-D7 systems. In a previous analysis of a model with a running gauge coupling a baryonic phase was shown to exist to arbitrarily large chemical potential. Here we explore this phase in a more generic phenomenological setting with a step function dilaton profile. The change in dilaton generates a linear confining $\bar{q}q$ potential and opposes the screening effect of temperature. We show that the persistence of the baryonic phase depends on the step size and that QCD-like phase diagrams can be described. The baryonic phase's existence is qualitatively linked to the existence of confinement in Wilson loop computations in the background.
description: 21 pages, 7 figures
Kondo QED: The Kondo effect and photon trapping in a two-impurity Anderson model ultra-strongly coupled to light
Creators: name: Kuo, Po-Chen
name: Lambert, Neill
name: Cirio, Mauro
name: Huang, Yi-Te
name: Nori, Franco
name: Chen, Yueh-Nan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The Kondo effect is one of the most studied examples of strongly correlated quantum many-body physics. Another type of strongly correlated physics that has only recently been explored in detail (and become experimentally accessible) is that of ultrastrong coupling between light and matter. Here, we study a system which we denote as "Kondo QED") that combines both phenomena, consisting of a two-impurity Anderson model ultra-strongly coupled to a single-mode cavity. While presented as an abstract model, it is relevant for a range of future hybrid cavity-QED systems. Using the hierarchical equations of motion approach we show that the ultrastrong coupling of cavity photons to the electronic states (impurity) noticeably suppresses the electronic Kondo resonance due to the destruction of many-body correlations of the Kondo cloud. We observe this transfer of correlations from the Kondo cloud to the cavity by computing the entropy and mutual information of the impurity-cavity subsystems. In addition, in the weak lead-coupling limit and at zero-bias, the model exhibits a ground-state photon accumulation effect originating entirely from counter-rotating terms in the impurity-cavity interaction. Interestingly, in the strong lead-coupling limit, this accumulation is ``Kondo-enhanced'' by new transition paths opening when increasing the hybridization to the leads. This suggests a new mechanism for the generation of real photons from virtual states. We further show that the suppression of the Kondo effect is stable under broadening of the cavity resonance as a consequence of the interaction to an external bosonic continuum. Our findings pave the way for the simultaneous control of both the Kondo QED effect and a photon accumulation effect using the ultrastrong coupling of light and matter.
description: 23 pages, 11 figures, 2 tables
Evolution of sunspot properties during solar cycle 23
Creators: name: Watson, Fraser T.
name: Fletcher, Lyndsay
name: Marshall, Stephen
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The long term study of the Sun is necessary if we are to determine the evolution of sunspot properties and thereby inform modeling of the solar dynamo, particularly on scales of a solar cycle. We aim to determine a number of sunspot properties over cycle 23 using the uniform database provided by the SOHO Michelson Doppler Imager data. We focus in particular on their distribution on the solar disk, maximum magnetic field and umbral/penumbral areas. We investigate whether the secular decrease in sunspot maximum magnetic field reported in Kitt Peak data is present also in MDI data. We have used the Sunspot Tracking And Recognition Algorithm (STARA) to detect all sunspots present in the SOHO Michelson Doppler Imager continuum data giving us 30 084 separate detections. We record information on the sunspot locations, area and magnetic field properties and corresponding information for the umbral areas detected within the sunspots, and track them through their evolution. We find the total visible umbral area is 20-40% of the total visible sunspot area at all stages of the solar cycle. We find that the number of sunspots observed follows the Solar Influences Data Centre International Sunspot Number with some interesting deviations. Finally, we use the magnetic information in our catalogue to study the long term variation of magnetic field strength within sunspot umbrae and find that it increases and decreases along with the sunspot number. However, if we were to assume a secular decreaseas was reported in the Kitt Peak data and take into account sunspots throughout the whole solar cycle we would find the maximum umbral magnetic fields to be decreasing by 23.6 \pm 3.9 Gauss per year, which is far less than has previously been observed by other studies. If we only look at the declining phase of cycle 23 we find the decrease in sunspot magnetic fields to be 70 Gauss per year.
description: 8 pages, 7 figures, accepted for publication in Astronomy and Astrophysics
Inhibitory Neural Coding in the Deep Cerebellar Nuclei
Creators: name: Dykstra, Steven
Publisher: name: Graduate Studies
Year: 2015
Subjects: Electrophysiology
Deep Cerebellar Nuclei
Rebound Bursts
Neural Coding

description: This study examines the response of Weak and Transient burst deep cerebellar nuclear (DCN) neurons when they are stimulated by physiological patterns of Purkinje cell inhibitory input in vitro. We also report the DCN neurons response to regular patterns of Purkinje cell firing defined by a CV2 analysis, as well as complex spike discharge. Currently the functional significance, and input parameters that generate rebound bursts in the DCN are unknown. Here we report that there are subtle differences in the Weak and Transient cell burst response suggesting the presence of differential coding by DCN neurons. Reverse correlation between DCN cell bursts and Purkinje cell input revealed an elevation-pause pattern of Purkinje cell firing triggers a rebound burst, while CV2-defined patterns and complex spikes failed to reliably trigger rebound responses. This work identifies a framework for future studies to investigate the relationship between Purkinje cell input and DCN output.
Hodge numbers of motives attached to Kloosterman and Airy moments
Creators: name: Qin, Yichen
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Geometry (math.AG)
subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: Fresán, Sabbah, and Yu constructed motives $\mathrm{M}_{n+1}^k(\mathrm{Kl})$ over $\mathbb{Q}$ encoding symmetric power moments of Kloosterman sums in $n$ variables. When $n=1$, they use the irregular Hodge filtration on the exponential mixed Hodge structure associated with $\mathrm{M}_{2}^k(\mathrm{Kl})$ to compute the Hodge numbers of $\mathrm{M}_{2}^k(\mathrm{Kl})$, which turn out to be either $0$ or $1$. In this article, I explain how to compute the (irregular) Hodge numbers of $\mathrm{M}_{n+1}^k(\mathrm{Kl})$ for $n=2$ or for general values of $n$ such that $\gcd(k,n+1)=1$. I will also discuss related motives attached to Airy moments constructed by Sabbah and Yu. In particular, the computation shows that there are Hodge numbers bigger than $1$ in most cases.
description: final version, to appear in Crelle's Journal
Immunocamouflage : the biophysical and biological basis of immunoprotection by grafted methoxypoly(ethylene glycol)
Creators: name: Le, Yevgeniya
Publisher: name: University of British Columbia
Year: 2010

description: Development of novel approaches for the direct immunomodulation of allogeneic donor cells would have significant utility in tissue transplantation. Immunocamouflage of cell surfaces by covalently grafted methoxypoly(ethylene glycol) (mPEG; PEGylation) has emerged as a promising approach. While previous studies demonstrated the in vitro and in vivo efficacy of immunocamouflaged allogeneic cells and viruses, the biophysical mechanisms of immunoprotection have not been well-defined due to the labile nature of biological samples. To overcome this limitation, polystyrene latex particles (1.2 and 8.0 µm) were used to elucidate the biophysical mechanisms of immunocamouflage via the effects of the chemical and physical properties of the polymer, as well as the consequences of target size. These findings were correlated with the biological studies utilizing human red blood cells and lymphocytes. It was demonstrated that the two biophysical mechanisms were responsible for the immunocamouflage of PEGylated surfaces: 1) hydrodynamic shielding of surface charge; and 2) steric exclusion of macromolecules from the surface. Surface charge camouflage of latex particles and erythrocytes was best achieved with long polymer chains, regardless of the target size. However, inhibition of surface-macromolecule interactions indicated a target size dependence. The biophysical latex model demonstrated that short chain polymers (2 kDa) were more effective at preventing protein adsorption to small beads (1.2 µm), while long chain polymers (20 kDa) exhibited increased efficacy on large particles (8.0 µm). Consistent with the biophysical model, immunocamouflage of lymphocytes (~10 µm) was best achieved using long chain polymers as measured by: 1) inhibition of antigen-antibody binding (CD3, CD4 and CD28); and 2) allorecognition in a 2-way mixed lymphocyte reaction. The biological model also demonstrated that cell surface topography and antigen localization were critical in selecting the optimal polymer size. Importantly, PEGylation did not result in any cellular toxicity at immunoprotective levels that rendered modified surfaces more biocompatible. Thus, these studies delineated the biophysical mechanisms of immunocamouflage defined by the chemical and physical parameters of the polymer and influenced by target size and surface complexity. Cell or tissue specific optimization of these factors will be critical for the efficient immunocamouflage of allogeneic cells in transfusion and transplantation medicine.
Lyapunov exponents in a Sachdev-Ye-Kitaev-type model with population imbalance in the conformal limit and beyond
Creators: name: Shankar, A. S.
name: Fremling, M.
name: Plugge, S.
name: Fritz, L.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The Sachdev-Ye-Kitaev (SYK) model shows chaotic behavior with a maximal Lyapunov exponent. In this paper, we investigate the four-point function of a SYK-type model numerically, which gives us access to its Lyapunov exponent. The model consists of two sets of Majorana fermions, called A and B, and the interactions are restricted to being exclusively pairwise between the two sets, not within the sets. We find that the Lyapunov exponent is still maximal at strong coupling. Furthermore, we show that even though the conformal dimensions of the A and B fermions change with the population ratio, the Lyapunov exponent remains constant, not just in the conformal limit where it is maximal, but also in the intermediate and weak coupling regimes.
description: 12 pages, 8 figures. Comments welcome
Is SGR 0418+5729 indeed a waning magnetar ?
Creators: name: Turolla, R.
name: Zane, S.
name: Pons, J. A.
name: Esposito, P.
name: Rea, N.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: SGR 0418+5729 is a transient Soft Gamma-ray Repeater which underwent a major outburst in June 2009, during which the emission of short bursts was observed. Its properties appeared quite typical of other sources of the same class until long-term X-ray monitoring failed to detect any period derivative. The present upper limit on $\dot P$ implies that the surface dipole field is $B_p\lesssim 7.5\times 10^{12}\ {\rm G}$ (Rea et al 2010), well below those measured in other Soft Gamma-ray Repeaters (SGRs) and in the Anomalous X-ray Pulsars (AXPs), a group of similar sources. Both SGRs and AXPs are currently believed to be powered by ultra-magnetized neutron stars (magnetars, $B_p\approx 10^{14}$--$10^{15}\ {\rm G}$). SGR 0418+5729 hardly seems to fit in such a picture. We show that the magneto-rotational properties of SGR 0418+5729 can be reproduced if this is an aged magnetar, $\approx 1\ {\rm Myr}$ old, which experienced substantial field decay. The large initial toroidal component of the internal field required to match the observed properties of SGR 0418+5729 ensures that crustal fractures, and hence bursting activity, can still occur at present time. The thermal spectrum observed during the outburst decay is compatible with the predictions of a resonant compton scattering model (as in other SGRs/AXPs) if the field is low and the magnetospheric twist moderate.
description: 8 pages, 4 figures, accepted for publication in ApJ
Output Feedback Stochastic MPC with Hard Input Constraints
Creators: name: Joa, Eunhyek
name: Bujarbaruah, Monimoy
name: Borrelli, Francesco
Publisher: name: arXiv
Year: 2023
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: We present an output feedback stochastic model predictive controller (SMPC) for constrained linear time-invariant systems. The system is perturbed by additive Gaussian disturbances on state and additive Gaussian measurement noise on output. A Kalman filter is used for state estimation and an SMPC is designed to satisfy chance constraints on states and hard constraints on actuator inputs. The proposed SMPC constructs bounded sets for the state evolution and a tube-based constraint tightening strategy where the tightened constraints are time-invariant. We prove that the proposed SMPC can guarantee an infeasibility rate below a user-specified tolerance. We numerically compare our method with a classical output feedback SMPC with simulation results which highlight the efficacy of the proposed algorithm.
description: IEEE American Control Conference (ACC) 2023, May 31 - June 2, San Diego, CA, USA
Rapid Mid-Infrared Variability in Protostellar Disks
Creators: name: Ke, Te T.
name: Huang, Hao
name: Lin, Douglas N. C.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Spectral energy distribution (SED) in protostellar disks is determined by the disks'internal dissipation and reprocessing of irradiation from their host stars. Around T Tauri stars, most mid-infrared (MIR) radiation (in a few to a few ten μm wavelength range) emerge from regions around a fraction to a few AU's. This region is interesting because it contains both the habitable zone and the snow line. Recent observations reveal that SED variations, in the MIR wavelength range. These variations are puzzling because they occur on time scale (a few days) which is much shorter than the dynamical (months to years) time scale at 1AU to a few AU's. They are probably caused by shadows casted by inner onto outer disk regions. Interaction between disks and their misaligned magnetized host stars can lead to warped structure and periodic SED modulations. Rapid aperiodic SED variations may also be induced by observed X-ray flares from T Tauri stars. These flares can significantly modulate the ionization fraction of the gas and the net charge carried by the grains near the surface of the inner disk. The newly charged grains may be accelerated by the stellar or disk magnetic field and adjust their distances from the midplane. Shadows casted by these grains attenuates the flux of stellar photons irradiated onto regions at several AU's from the central stars. We use this model to account for the observed rapid aperiodic SED variabilities. We suggest regular monitoring of SED variations will not only provide valuable information on the distribution of the disk aspect ratio near the habitable zone but also provide a probe on the interaction between the inner regions of the disk with the magnetosphere of their host stars.
description: 23 pages, 7 figures
Mountain Town with A Vision: A Case Study In Sustainable Community Development in Revelstoke, British Columbia
Creators: name: Feick, Jenny L.
Publisher: name: Environmental Design
Year: 1995
Subjects: subject: Sustainability
subject: Sustainable development
subject: Community development
subject: Sustainable community development
subject: Strategic Planning
subject: Future state visioning
subject: Environmental citizenship
subject: Ecosystem-based management
subject: Forestry
subject: Revelstoke
subject: British Columbia
subject: Community development - British Columbia - Revelstoke
subject: Sustainable development - British Columbia - Revelstoke
subject: Revelstoke (B.C.) - Economic conditions

description: Bibliography: p. R2-R32.
description: This Masters Degree Project applies the concepts of Sustainable Community Development (SCD) and Future State Visioning (FSV) to a specific case study --­Revelstoke, in interior British Columbia. This community is struggling to break from its "boom and bust" economy by setting a vision to achieve a sustainable community by balancing environmental, social and economic values. The MDP describes, interprets and assesses Revelstoke's vision setting process and Vision Statement using triangulation of both quantitative and qualitative methods. The research assesses the potential utility of the process in SCD and the vision's initial use. Community visioning shows potential as a tool in SCD if people involved in the process apply principles to other processes, decisions and documents affecting the community's future. Revelstoke vision-setting process would have been more effective had it involved broad based community participation, and if community-supported definitions of key concepts would have been developed.
Using ecological momentary assessment to characterize dynamic patterns of e-cigarette use in adults planning to quit e-cigarettes
Creators: name: Rosen, Rachel Leni
Publisher: name: No Publisher Supplied
Year: 2023

description: E-cigarettes are the second most used nicotine/tobacco product. Given growing evidence that many adults who use e-cigarettes want to quit e-cigarettes, it is essential to begin to understand patterns of e-cigarette use and cessation behavior, as a step toward developing e-cigarette cessation interventions for the millions of adults who use e-cigarettes who may want or require cessation interventions. The current study aimed to 1) characterize patterns of e-cigarette use, cessation behavior, and putative contextual, person-level, and product-specific antecedents of quit attempts and 2) examine the association between variability in these contextual (i.e., non-nicotine substance use), person-level (i.e., mood, pain, fatigue, cravings, confidence in ability to quit, importance of quitting, readiness to quit, commitment to quitting e-cigarettes, intention to quit e-cigarettes), and product-specific (i.e., e-liquid flavor) factors and concurrent or near-term subsequent e-cigarette quit attempts. Participants (N = 107) included adults (18-60) who reported current daily e-cigarette use and interest in quitting e-cigarettes within the next 30 days. Participants were sent five brief surveys per day for 30 days. Multi-level logistic regression was used to examine associations between variability in contextual, person-level, and product-specific factors and odds of making a quit attempt during the same day and subsequent days. Sixty-five percent of the sample reported a quit attempt during the study period. Increased confidence in quitting tomorrow and increased intention to quit tomorrow, compared to one’s average levels increased their odds of making a quit attempt the next day (p < .01). Increased fatigue and pain, relative to one’s own average, were associated with reduced likelihood of making a quit attempt (p <.01). There was no significant effect of non-nicotine substance use or e-liquid flavor on concurrent or near-term future attempts to quit e-cigarettes. Findings from the current study add to the growing literature suggesting that people who use e-cigarettes are initiating quit attempts. The current study has the potential to inform the development or refinement of e-cigarette cessation interventions by identifying risk factors (e.g., fatigue, pain) for continued e-cigarette use and the optimal timing (e.g., in the hours/day prior to a quit attempt) of intervention delivery.
Hydrodynamic irreversibility of non-Brownian suspensions in highly confined duct flow
Creators: name: Antolik, John T.
name: Howard, Amanda
name: Vereda, Fernando
name: Ionkin, Nikolay
name: Maxey, Martin
name: Harris, Daniel M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The irreversible behavior of a highly confined non-Brownian suspension of spherical particles at low Reynolds number in a Newtonian fluid is studied experimentally and numerically. In experiment, the suspension is confined in a thin rectangular channel that prevents complete particle overlap in the narrow dimension and subjected to an oscillatory pressure-driven flow. In the small cross-sectional dimension particles rapidly separate to the walls, whereas in the large dimension features reminiscent of shear-induced migration in bulk suspensions are recovered. Furthermore, as a consequence of the channel geometry and the development and application of a single-camera particle tracking method, three-dimensional particle trajectories are obtained that allow us to directly associate relative particle proximity with the observed migration. Companion simulations of a steadily flowing suspension highly confined between parallel plates are conducted using the Force Coupling Method which also show rapid migration to the walls as well as other salient features observed in the experiment. While we consider relatively low volume fractions compared to most prior work in the area, we nevertheless observe significant and rapid migration which we attribute to the high degree of confinement.
description: 12 figures
ILM-FAN VA TA'LIMDA INNOVATSION YONDASHUVLAR, MUAMMOLAR, TAKLIF VA YECHIMLAR
Creators: name: Ismoilova, Mohinur
Publisher: name: Zenodo
Year: 2025

description: Ushbu maqola ilm-fan va ta’lim sohasida innovatsion yondashuvlarning o‘rni va muhimligini tahlil qiladi. Innovatsion texnologiyalar, metodologiyalar va pedagogik uslublarning ta’lim tizimiga joriy etilishi orqali ta’limning samaradorligini oshirish, ta’lim jarayonlarini zamonaviylashtirish va ilmiy tadqiqotlarni rivojlantirish mumkin. Maqolada ilm-fan va ta’limda yuzaga kelayotgan asosiy muammolar, masalan, raqamli ta’lim tizimlarining o‘rganilishi, o‘qituvchilarning raqamli ko‘nikmalarini oshirish, hamda ta’limda tengsizlik masalalari ko‘rib chiqiladi. Shuningdek, ushbu muammolarni bartaraf etish uchun takliflar va yechimlar keltirilgan. Maqola ilmiy tadqiqotlarning samarali olib borilishi, ta’lim jarayonlarining innovatsion usullar bilan boyitilishi va zamonaviy ta’lim texnologiyalaridan foydalanish bo‘yicha muhim maslahatlarni taqdim etadi.
Recomendaciones en SST para Salones de Belleza y Barbería
Creators: name: Pérez Fernández, Blanca Johanna
name: Almanza Caro, Francia Milena
Publisher: name: Zenodo
Year: 2023
Subjects: Peligro
Ruido
Postura
Contaminantes químicos
Elemento de Protección Personal

description: Documento derivado de una investigación en el Barrio El Rodeo y Zonas aledañas que recoge algunas recomendaciones dirigidas al sector económico de belleza como barberías, peluquerías y salones de belleza.
Borel sets which are null or non-$σ$-finite for every translation invariant measure
Creators: name: Elekes, Márton
name: Keleti, Tamás
Publisher: name: arXiv
Year: 2011
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: Primary 28C10, Secondary 28A78, 43A05

description: We show that the set of Liouville numbers is either null or non-$σ$-finite with respect to every translation invariant Borel measure on $\RR$, in particular, with respect to every Hausdorff measure $\iH^g$ with gauge function $g$. This answers a question of D. Mauldin. We also show that some other simply defined Borel sets like non-normal or some Besicovitch-Eggleston numbers, as well as all Borel subgroups of $\RR$ that are not $F_σ$ possess the above property. We prove that, apart from some trivial cases, the Borel class, Hausdorff or packing dimension of a Borel set with no such measure on it can be arbitrary.
Mixed-dimensional coupled finite elements in FEniCS
Creators: name: Daversin-Catty, Cécile
name: Rognes, Marie E.
Publisher: name: Zenodo
Year: 2021

description: Mixed-dimensional partial differential equations (PDEs) are equations coupling unknown fields defined over domains of differing topological dimension. Such mixed-dimensional PDEs naturally arise in a wide range of fields including geology, bio-medicine, and fracture mechanics. Mixed-dimensional models can also be used to impose non-standard conditions over a subspace of lower dimension such as a part of the boundary or an interface between two domains, through a Lagrange multiplier.
 Finite element discretizations of mixed-dimensional PDEs involve nested meshes of heterogeneous topological dimension. The assembly of such systems is non-standard and non-trivial especially with regard to the terms involved in the interactions between the different domains. In other words, automated solution of mixed-dimensional PDEs requires the design of both generic high level software abstractions and lower level algorithms.
 The FEniCS project aims at automating the numerical solution of mathematical models based on PDEs using finite element methods, and is organized as an open source collection of software components. A core feature is a high-level domain-specific language for finite element spaces and variational forms close to mathematical syntax. While external FEniCS-based packages have been developed for simulating mixed-dimensional problems, there is an important need for embedding these features as
 an intrinsic part of the FEniCS library. We introduce an automated framework dedicated to mixed-dimensional problems addressing this gap, which has already been used for a wide range of applications including fluid flow models and ionic electrodiffusion.
 This talk gives an overview of the abstractions and algorithms involved. The introduced tools will be illustrated by concrete examples of applications in biomedicine.
A Myersonian Framework for Optimal Liquidity Provision in Automated Market Makers
Creators: name: Milionis, Jason
name: Moallemi, Ciamac C.
name: Roughgarden, Tim
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Science and Game Theory (cs.GT)
subject: Theoretical Economics (econ.TH)
subject: Mathematical Finance (q-fin.MF)
subject: Trading and Market Microstructure (q-fin.TR)
subject: FOS: Computer and information sciences
subject: FOS: Economics and business

description: In decentralized finance ("DeFi"), automated market makers (AMMs) enable traders to programmatically exchange one asset for another. Such trades are enabled by the assets deposited by liquidity providers (LPs). The goal of this paper is to characterize and interpret the optimal (i.e., profit-maximizing) strategy of a monopolist liquidity provider, as a function of that LP's beliefs about asset prices and trader behavior. We introduce a general framework for reasoning about AMMs based on a Bayesian-like belief inference framework, where LPs maintain an asset price estimate. In this model, the market maker (i.e., LP) chooses a demand curve that specifies the quantity of a risky asset to be held at each dollar price. Traders arrive sequentially and submit a price bid that can be interpreted as their estimate of the risky asset price; the AMM responds to this submitted bid with an allocation of the risky asset to the trader, a payment that the trader must pay, and a revised internal estimate for the true asset price. We define an incentive-compatible (IC) AMM as one in which a trader's optimal strategy is to submit its true estimate of the asset price, and characterize the IC AMMs as those with downward-sloping demand curves and payments defined by a formula familiar from Myerson's optimal auction theory. We generalize Myerson's virtual values, and characterize the profit-maximizing IC AMM. The optimal demand curve generally has a jump that can be interpreted as a "bid-ask spread," which we show is caused by a combination of adverse selection risk (dominant when the degree of information asymmetry is large) and monopoly pricing (dominant when asymmetry is small). This work opens up new research directions into the study of automated exchange mechanisms from the lens of optimal auction theory and iterative belief inference, using tools of theoretical computer science in a novel way.
description: 20 pages, to appear in the 15th Innovations in Theoretical Computer Science conference (ITCS 2024)
The Nub of an Automorphism of a Totally Disconnected, Locally Compact Group
Creators: name: Willis, George
Publisher: name: arXiv
Year: 2011
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics

description: To any automorphism, $α$, of a totally disconnected, locally compact group, $G$, there is associated a compact, $α$-stable subgroup of $G$, here called the \emph{nub} of $α$, on which the action of $α$ is topologically transitive. Topologically transitive actions of automorphisms of compact groups have been studied extensively in topological dynamics and results obtained transfer, via the nub, to the study of automorphisms of general locally compact groups. A new proof that the contraction group of $α$ is dense in the nub is given, but it is seen that the two-sided contraction group need not be dense. It is also shown that each pair $(G,α)$, with $G$ compact and $α$ topologically transitive, is an inverse limit of pairs that have `finite depth' and that analogues of the Schreier Refinement and Jordan-Hölder Theorems hold for pairs with finite depth.
The field of moduli of varieties with a structure
Creators: name: Bresciani, Giulio
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: If $X$ is a variety with an additional structure $ξ$, such as a marked point, a divisor, a polarization, a group structure and so forth, then it is possible to study whether the pair $(X,ξ)$ is defined over the field of moduli. There exists a precise definition of ``algebraic structures'' which covers essentially all of the obvious concrete examples. We prove several formal results about algebraic structures. There are immediate applications to the study of fields of moduli of curves and finite sets in $\mathbb{P}^{2}$, but the results are completely general. Fix $G$ a finite group of automorphisms of $X$, a $G$-structure is an algebraic structure with automorphism group equal to $G$. First, we prove that $G$-structures on $X$ are in a $1:1$ correspondence with twisted forms of $X/G\dashrightarrow\mathcal{B} G$. Secondly we show that, under some assumptions, every algebraic structure on $X$ is equivalent to the structure given by some $0$-cycle. Third, we give a cohomological criterion for checking the existence of $G$-structures not defined over the field of moduli. Fourth, we identify geometric conditions about the action of $G$ on $X$ which ensure that every $G$-structure is defined over the field of moduli.
Modeling fluid flow in perivascular networks
Creators: name: Daversin-Catty, Cécile
name: Vinje, Vegard
name: Gjerde, Ingeborg
name: Kent-André Mardal
name: Rognes, Marie E.
Publisher: name: Zenodo
Year: 2022

description: Flow of cerebrospinal fluid in perivascular spaces is one of the key mechanisms underlying the brain clearance processes. While experimental studies have demonstrated net flow along the perivascular space, the mechanisms involved remain disputed. We have developed a three-dimensional model simulating perivascular fluid flow in realistic geometries obtained from patient data to investigate a set of plausible mechanisms. This model was able to generate net and oscillatory perivascular flow, quantitatively comparable with experimental findings. However, such a three-dimensional model becomes prohibitively expensive when it
 comes to complex perivascular networks. We introduce a geometrically-reduced perivascular flow model based on topologically one-dimensional centerlines of the perivascular network, providing approximations of the cross-section average pressure and cross-section flux. The agreement between full and reduced model predictions demonstrates the robustness of the
 reduced model, with a gain in computational time of several orders of magnitude.
 In this talk, we will present our three-dimensional perivascular flow model together with the resulting insights regarding mechanisms involved in brain clearance. We will then introduce the geometrically-reduced model and its ability to simulate perivascular flow patterns in complex perivascular networks.
Kumar's criterion modulo p
Creators: name: Juteau, Daniel
name: Williamson, Geordie
Publisher: name: arXiv
Year: 2012
Subjects: subject: Algebraic Geometry (math.AG)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: We prove that equivariant multiplicities may be used to determine whether attractive fixed points on T-varieties are p-smooth. This gives a combinatorial criterion for the determination of the p-smooth locus of Schubert varieties for all primes p.
description: 20 pages, 1 TiKZ figure. DVI may not display correctly, PDF is preferred
Inhomogeneities on all scales at a phase transition altered by disorder
Creators: name: Balog, Ivan
name: Uzelac, Katarina
Publisher: name: arXiv
Year: 2012
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We have done a finite-size scaling study of a continuous phase transition altered by the quenched bond disorder, investigating systems at quasicritical temperatures of each disorder realization by using the equilibriumlike invaded cluster algorithm. Our results indicate that in order to access the thermal critical exponent $y_τ$, it is necessary to average the free energy at quasicritical temperatures of each disorder configuration. Despite the thermal fluctuations on the scale of the system at the transition point, we find that spatial inhomogeneities form in the system and become more pronounced as the size of the system increases. This leads to different exponents describing rescaling of the fluctuations of observables in disorder and thermodynamic ensembles.
description: 11 pages, 4 figures
Self-supervised learning-based general laboratory progress pretrained model for cardiovascular event detection
Creators: name: Chen, Li-Chin
name: Hung, Kuo-Hsuan
name: Tseng, Yi-Ju
name: Wang, Hsin-Yao
name: Lu, Tse-Min
name: Huang, Wei-Chieh
name: Tsao, Yu
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: The inherent nature of patient data poses several challenges. Prevalent cases amass substantial longitudinal data owing to their patient volume and consistent follow-ups, however, longitudinal laboratory data are renowned for their irregularity, temporality, absenteeism, and sparsity; In contrast, recruitment for rare or specific cases is often constrained due to their limited patient size and episodic observations. This study employed self-supervised learning (SSL) to pretrain a generalized laboratory progress (GLP) model that captures the overall progression of six common laboratory markers in prevalent cardiovascular cases, with the intention of transferring this knowledge to aid in the detection of specific cardiovascular event. GLP implemented a two-stage training approach, leveraging the information embedded within interpolated data and amplify the performance of SSL. After GLP pretraining, it is transferred for TVR detection. The proposed two-stage training improved the performance of pure SSL, and the transferability of GLP exhibited distinctiveness. After GLP processing, the classification exhibited a notable enhancement, with averaged accuracy rising from 0.63 to 0.90. All evaluated metrics demonstrated substantial superiority (p < 0.01) compared to prior GLP processing. Our study effectively engages in translational engineering by transferring patient progression of cardiovascular laboratory parameters from one patient group to another, transcending the limitations of data availability. The transferability of disease progression optimized the strategies of examinations and treatments, and improves patient prognosis while using commonly available laboratory parameters. The potential for expanding this approach to encompass other diseases holds great promise.
description: published in IEEE Journal of Translational Engineering in Health & Medicine
Quantum lattice models that preserve continuous translation symmetry
Creators: name: Lewis, Dominic G.
name: Kempf, Achim
name: Menicucci, Nicolas C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Bandlimited approaches to quantum field theory offer the tantalizing possibility of working with fields that are simultaneously both continuous and discrete via the Shannon Sampling Theorem from signal processing. Conflicting assumptions in general relativity and quantum field theory motivate the use of such an appealing analytical tool that could thread the needle to meet both requirements. Bandlimited continuous quantum fields are isomorphic to lattice theories, yet without requiring a fixed lattice. Any lattice with a required minimum spacing can be used. This is an isomorphism that avoids taking the limit of the lattice spacing going to zero. In this work, we explore the consequences of this isomorphism, including the emergence of effectively continuous symmetries in quantum lattice theories. One obtains conserved lattice observables for these continuous symmetries, as well as a duality of locality from the two perspectives. We expect this work and its extensions to provide useful tools for considering numerical lattice models of continuous quantum fields arising from the availability of discreteness without a fixed lattice, as well as offering new insights into emergent continuous symmetries in lattice models and possible laboratory demonstrations of these phenomena.
description: 16 pages, 5 figures
Revealing complexities when adult readers engage in the credibility evaluation of social media posts
Creators: name: Kuutila, Miikka
name: Kiili, Carita
name: Kupiainen, Reijo
name: Huusko, Eetu
name: Li, Junhao
name: Hosio, Simo
name: Mäntylä, Mika
name: Coiro, Julie
name: Kiili, Kristian
Publisher: name: arXiv
Year: 2023
Subjects: subject: Social and Information Networks (cs.SI)
subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: The present study investigates the role of source characteristics, evidence quality, crowdsourcing platform, and prior beliefs of the topic in adult readers' credibility evaluations of short healthrelated social media posts. Researchers designed content for the posts concerning five health topics by manipulating source characteristics (source's expertise, gender, and ethnicity), accuracy of the claims, and evidence quality (research evidence, testimony, consensus, and personal experience) in the posts. Then, accurate and inaccurate posts varying in these other manipulated aspects were computer-generated. Crowdworkers (N = 844) recruited from two platforms were asked to evaluate the credibility of ten social media posts, resulting in 8380 evaluations. Before credibility evaluation, participants' prior beliefs on the topics of the posts were assessed. Results showed that prior belief consistency and source expertise most affected the perceived credibility of accurate and inaccurate social media posts after controlling for the topic of the post. In contrast, the quality of evidence supporting the health claim mattered relatively little. In addition, the data collection platform had a notable impact, such that posts containing inaccurate claims were much more likely to be rated higher on one platform compared to the other. Implications for credibility evaluation theory and research are discussed.
description: 25 pages, 5 figures including the appendix. Accepted to Computers in Human Behavior
Statistical Age-of-Information Optimization for Status Update over Multi-State Fading Channels
Creators: name: Xiao, Yuquan
name: Du, Qinghe
Publisher: name: arXiv
Year: 2023
Subjects: subject: Information Theory (cs.IT)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Age of information (AoI) is a powerful metric to evaluate the freshness of information, where minimization of average statistics, such as the average AoI and average peak AoI, currently prevails in guiding freshness optimization for related applications. Although minimizing the statistics does improve the received information's freshness for status update systems in the sense of average, the time-varying fading characteristics of wireless channels often cause uncertain yet frequent age violations. The recently-proposed statistical AoI metric can better characterize more features of AoI dynamics, which evaluates the achievable minimum peak AoI under the certain constraint on age violation probability. In this paper, we study the statistical AoI minimization problem for status update systems over multi-state fading channels, which can effectively upper-bound the AoI violation probability but introduce the prohibitively-high computing complexity. To resolve this issue, we tackle the problem with a two-fold approach. For a small AoI exponent, the problem is approximated via a fractional programming problem. For a large AoI exponent, the problem is converted to a convex problem. Solving the two problems respectively, we derive the near-optimal sampling interval for diverse status update systems. Insightful observations are obtained on how sampling interval shall be tuned as a decreasing function of channel state information (CSI). Surprisingly, for the extremely stringent AoI requirement, the sampling interval converges to a constant regardless of CSI's variation. Numerical results verify effectiveness as well as superiority of our proposed scheme.
description: This paper has been accepted by IEEE Transactions on Vehicular Technology
Searching for Time-Dependent Axion Dark Matter Signals in Pulsars
Creators: name: Battye, R. A.
name: Keith, M. J.
name: McDonald, J. I.
name: Srinivasan, S.
name: Stappers, B. W.
name: Weltevrede, P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Axion dark matter can be converted into photons in the magnetospheres of neutron stars leading to a spectral line centred on the Compton wavelength of the axion. Due to the rotation of the star and the plasma effects in the magnetosphere the signal is predicted to be periodic with significant time variation - a unique smoking gun for axion dark matter. As a proof of principle and to develop the methodology, we carry out the first time domain search of the signal using data from PSR J2144$-$3933 taken as part of the MeerTIME project on MeerKAT telescope. We search for specific signal templates using a matched filter technique and discuss when a time-domain analysis (as is typically the case in pulsar observations) gives greater sensitivity to the axion-coupling to photons in comparison to a simple time-averaged total flux study. We do not find any candidate signals and, hence, impose an upper limit on the axion-to-photon coupling of $g_{aγγ}<4\times 10^{-11}\,{\rm GeV}^{-1}$ over the mass range $m_{\rm a}=3.9-4.7\,μ{\rm eV}$ using this data. This limit relies on PSR J2144$-$3933 not being an extremely aligned rotator, as strongly supported by simple arguments based on the observed pulse profile width. We discuss the possibilities of improving this limit using future observations with MeerKAT and also SKA1-mid and the possibility of using other objects. Finally, to evade modelling uncertainties in axion radio signals, we also carry out a generic ``any periodic-signal search" in the data, finding no evidence for an axion signal.
description: 21 pages, 14 figures Published in PRD
Modelling and Simulation of Perivascular Fluid Flow: Dimension reduction and generalized finite element methods
Creators: name: Gjerde, Ingeborg
name: Rognes, Marie
Publisher: name: Zenodo
Year: 2021

description: In this work, we consider a mathematical model relevant for studying the mechanisms that
 potentially underlie the development of Alzheimer’s disease. In particular, we discuss the
 glymphatic system of the brain; i.e. the network of vessels that have been hypothesized to clear
 waste from the central nervous system. Recent evidence suggests that the disruption of this
 system contributes to the accumulation of amyloid-beta in the brain, which is one of the key
 hallmarks in the development of Alzheimer’s disease.
 According to the glymphatic theory, cerebrospinal fluid (CSF) flows in the perivascular space
 surrounding the arteries of the brain. In developing mathematical models describing this
 process, one central issue is dealing with the scale disparity between blood vessels and brain
 tissue. To do so, we employ a mixed-dimensional PDE in which the brain is considered a 3D
 domain embedded with a 1D network representing the perivascular space. We use Darcy’s law
 to model the flow in each domain, and couple them by use of a filtration law and a (2D)
 generalized Dirac source term as derived in [1]. Finally, in attempt to capture the steep pressure gradients
 expected around the (1D) perivascular spaces, we further introduce an enrichment of the
 finite element basis functions.
Nonlocal appearance of a macroscopic angular momentum
Creators: name: Paraoanu, G. S.
name: Healey, R.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We discuss a type of measurement in which a macroscopically large angular momentum (spin) is "created" nonlocally by the measurement of just a few atoms from a double Fock state. This procedure apparently leads to a blatant nonconservation of a macroscopic variable - the local angular momentum. We argue that while this gedankenexperiment provides a striking illustration of several counter-intuitive features of quantum mechanics, it does not imply a non-local violation of the conservation of angular momentum.
description: 10 pages, 1 figure